# Cursor Chat: ai-agent-book

## Metadata
- **Project**: ai-agent-book
- **Path**: `/Users/boj`
- **Date**: 2025-10-06 20:46:11
- **Session ID**: `8c1d391f-4769-47ad-a92c-557b7c53ebc2`

## Conversation

### 👤 You

I have three hosts bsql-storage.01.me,	
bsql-host1.01.me, 	
bsql-host2.01.me

in a same rack. bsql-host1.01.me and bsql-host2.01.me have Proxmox VE PVE installed. I want to mount the 10TB storage from the storage host as the storage for the PVE VMs. How to do it?

debian@debian100:~$ df -lh
Filesystem      Size  Used Avail Use% Mounted on
udev            3.9G     0  3.9G   0% /dev
tmpfs           795M  480K  794M   1% /run
/dev/vda2       9.9T  840G  8.6T   9% /
tmpfs           3.9G     0  3.9G   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           795M     0  795M   0% /run/user/1000

---

### 🤖 Cursor Assistant

I'll help you set up the 10TB storage from bsql-storage.01.me as shared storage for your Proxmox VE hosts. The most common and straightforward approach for this scenario is **NFS (Network File System)**.

## Solution Overview

Here's the recommended setup:

### Step 1: Set up NFS Server on bsql-storage.01.me

```bash
# On bsql-storage.01.me

# Install NFS server
sudo apt update
sudo apt install nfs-kernel-server -y

# Create a directory for PVE storage
sudo mkdir -p /export/pve-storage

# Set proper permissions
sudo chown nobody:nogroup /export/pve-storage
sudo chmod 755 /export/pve-storage

# Configure NFS exports
sudo nano /etc/exports
```

Add these lines to `/etc/exports`:
```
/export/pve-storage bsql-host1.01.me(rw,sync,no_subtree_check,no_root_squash)
/export/pve-storage bsql-host2.01.me(rw,sync,no_subtree_check,no_root_squash)
```

**Export options explained:**
- `rw` - read/write access
- `sync` - synchronous writes (safer for VMs)
- `no_subtree_check` - improves reliability
- `no_root_squash` - allows root on clients to access as root (needed for PVE)

```bash
# Apply the exports
sudo exportfs -ra

# Enable and start NFS server
sudo systemctl enable nfs-kernel-server
sudo systemctl start nfs-kernel-server

# Check status
sudo exportfs -v
```

### Step 2: Configure NFS Clients on PVE Hosts

```bash
# On both bsql-host1.01.me and bsql-host2.01.me

# Install NFS client
apt update
apt install nfs-common -y

# Test mount (optional, to verify it works)
mkdir -p /mnt/test
mount -t nfs bsql-storage.01.me:/export/pve-storage /mnt/test
df -h | grep test
umount /mnt/test
```

### Step 3: Add NFS Storage to Proxmox VE

You can do this via **Web UI** (easier) or **CLI**:

#### Option A: Via Proxmox Web UI

1. Log into Proxmox web interface
2. Navigate to: **Datacenter → Storage → Add → NFS**
3. Fill in:
   - **ID**: `nfs-storage` (or any name you prefer)
   - **Server**: `bsql-storage.01.me`
   - **Export**: `/export/pve-storage`
   - **Content**: Select what you want to store (VM images, Container images, ISO images, etc.)
4. Click **Add**

Repeat on both PVE hosts if they're not in a cluster, or do it once if they're clustered.

#### Option B: Via CLI

```bash
# On both PVE hosts (or once if clustered)
pvesm add nfs nfs-storage \
  --server bsql-storage.01.me \
  --export /export/pve-storage \
  --content images,rootdir,vztmpl,iso,backup

# Verify
pvesm status
```

### Step 4: Verify and Test

```bash
# Check storage status
pvesm status

# Create a test file
touch /mnt/pve/nfs-storage/test.txt

# Verify it appears on the storage host
# On bsql-storage.01.me:
ls -la /export/pve-storage/
```

## Alternative: iSCSI (if you prefer block-level storage)

If you need better performance or want block-level storage:

1. **On storage host**: Set up iSCSI target (using `tgt` or `targetcli`)
2. **On PVE hosts**: Connect to iSCSI target
3. **In Proxmox**: Add as LVM or LVM-thin storage

NFS is generally easier to manage and sufficient for most use cases.

## Performance Considerations

Since your hosts are in the same rack:
- Ensure they're connected via **10GbE network** for best VM performance
- Consider using a dedicated network interface for storage traffic
- Enable jumbo frames (MTU 9000) if your switch supports it

## High Availability Notes

For production environments, consider:
- Setting up the storage host with RAID for redundancy
- Using Proxmox clustering for automatic VM failover
- Implementing storage replication or backups

Would you like me to elaborate on any of these steps or discuss alternative storage solutions like Ceph for a more distributed approach?

---

### 👤 You

How can I make the two PVE hosts a cluster?

---

### 🤖 Cursor Assistant

I'll guide you through creating a Proxmox VE cluster with your two hosts. This will allow you to manage both hosts from a single interface and enable features like live migration and high availability.

## Creating a Proxmox VE Cluster

### Prerequisites

1. **Network requirements:**
   - Both hosts can reach each other via network
   - Same Proxmox VE version on both hosts (check with `pveversion`)
   - No VMs/containers currently running (or be prepared to stop them temporarily)
   - Time synchronization configured (NTP)

2. **Check versions:**
```bash
# On both hosts
pveversion
```

### Step 1: Create the Cluster (on first host)

```bash
# On bsql-host1.01.me (this will be the cluster master)

# Create cluster named "pve-cluster" (you can choose any name)
pvecm create pve-cluster

# Verify cluster status
pvecm status

# Check cluster nodes
pvecm nodes
```

### Step 2: Get Cluster Join Information

```bash
# On bsql-host1.01.me
pvecm status

# Get join information
pvecm expected 1
```

### Step 3: Join Second Host to Cluster

```bash
# On bsql-host2.01.me

# Join the cluster (you'll be prompted for root password of bsql-host1.01.me)
pvecm add bsql-host1.01.me

# If you have a specific IP/interface for cluster traffic, use:
# pvecm add bsql-host1.01.me --link0 <cluster-ip-of-host1>
```

**Important:** During the join process:
- You'll be asked for the root password of bsql-host1.01.me
- It will warn about losing the current configuration on bsql-host2 - this is expected
- All storage and VM configurations will be synced from the cluster

### Step 4: Verify Cluster

```bash
# On either host

# Check cluster status
pvecm status

# Should show:
# Cluster information
# Name: pve-cluster
# Config Version: X
# Cluster Id: XXXX
# Nodes: 2
# Expected votes: 2
# Total votes: 2
# Quorum: 2

# List all nodes
pvecm nodes

# Check corosync status
systemctl status corosync
systemctl status pve-cluster
```

### Step 5: Configure Cluster Network (Recommended)

If you have a dedicated network for cluster traffic:

```bash
# Edit corosync configuration
nano /etc/pve/corosync.conf
```

Add a second link for redundancy (optional but recommended):
```
totem {
    cluster_name: pve-cluster
    config_version: X
    ip_version: ipv4
    link_mode: passive
    secauth: on
    
    interface {
        linknumber: 0
        bindnetaddr: <primary-network>
    }
    
    interface {
        linknumber: 1
        bindnetaddr: <backup-network>
    }
}
```

Then reload:
```bash
systemctl reload corosync
```

### Step 6: Add Shared Storage to Cluster

Now that you have a cluster, add the NFS storage once and it will be available on both nodes:

```bash
# Run on any node (only once)
pvesm add nfs nfs-storage \
  --server bsql-storage.01.me \
  --export /export/pve-storage \
  --content images,rootdir,vztmpl,iso,backup

# This will automatically sync to both nodes
```

### Step 7: Test Live Migration

```bash
# Create a test VM on bsql-host1
qm create 999 --name test-vm --memory 512 --net0 virtio,bridge=vmbr0

# Start it
qm start 999

# Migrate to bsql-host2 (online migration)
qm migrate 999 bsql-host2 --online

# Check where it's running
qm status 999

# Delete test VM
qm destroy 999
```

## Important Cluster Considerations

### 1. **Quorum Requirements**

With 2 nodes, you have a problem: if one node fails, you lose quorum (need 2/2 votes). Solutions:

#### Option A: Add a QDevice (Recommended)
Set up a third lightweight device (can be on bsql-storage.01.me):

```bash
# On storage host (bsql-storage.01.me)
apt install corosync-qnetd

# On any PVE node
pvecm qdevice setup bsql-storage.01.me
```

#### Option B: Use `expected_votes` (Emergency only)
If one node dies:
```bash
# On surviving node
pvecm expected 1
```

### 2. **Fencing/Watchdog** (For HA)

If you plan to use High Availability:

```bash
# On both nodes
apt install watchdog
systemctl enable watchdog
systemctl start watchdog
```

### 3. **Cluster Configuration Best Practices**

```bash
# Set node priority (optional)
ha-manager set node:bsql-host1 --max_relocate 2 --max_restart 3

# Enable HA for a VM (example)
ha-manager add vm:100 --group <group> --max_restart 2 --max_relocate 2
```

## Web Interface Access

After clustering:
- Access via: `https://bsql-host1.01.me:8006` or `https://bsql-host2.01.me:8006`
- Both will show the same cluster view
- You can manage VMs on any node from any interface

## Troubleshooting

### Check cluster health:
```bash
pvecm status
journalctl -u corosync -n 50
journalctl -u pve-cluster -n 50
```

### Reset a node (if join fails):
```bash
# On the node you want to reset
systemctl stop pve-cluster
systemctl stop corosync
pmxcfs -l  # Local mode
rm -rf /etc/corosync/*
rm -rf /etc/pve/corosync.conf
rm -rf /var/lib/corosync/*
killall pmxcfs
systemctl start pve-cluster
```

### Common issues:
- **Firewall**: Ensure ports 5404-5405 UDP, 22 TCP, 8006 TCP are open
- **Time sync**: Both nodes must have synchronized time
- **Hostname resolution**: Hosts should resolve each other's hostnames

## Next Steps

1. ✅ Create cluster
2. ✅ Add shared storage
3. Consider setting up a QDevice for proper quorum
4. Configure HA groups if needed
5. Set up backup schedules
6. Test VM migration between hosts

Would you like help with any specific aspect like setting up the QDevice, configuring HA, or optimizing the cluster network?

---

### 👤 You

root@bojpve:~# pvecm add bsql-host2.01.me
Please enter superuser (root) password for 'bsql-host2.01.me': ********
Establishing API connection with host 'bsql-host2.01.me'
The authenticity of host 'bsql-host2.01.me' can't be established.
X509 SHA256 key fingerprint is 83:59:F9:CF:12:4A:47:0B:7C:33:3D:4E:4F:6F:D9:F5:E8:4C:B9:67:92:37:CB:B7:61:EB:92:96:AC:A0:AE:51.
Are you sure you want to continue connecting (yes/no)? yes
500 Can't connect to bsql-host2.01.me:8006 (hostname verification failed)

--
I'm using bsql-host2.01.me as master, and let host1 join. But it returned 500

---

### 🤖 Cursor Assistant

The error is due to SSL certificate hostname verification failing. The certificate on bsql-host2.01.me was likely generated with a different hostname. Here are solutions:

## Solution 1: Use IP Address Instead (Quick Fix)

```bash
# On bojpve (host1), use the IP address of bsql-host2.01.me
pvecm add <IP-ADDRESS-OF-bsql-host2.01.me>

# For example:
# pvecm add 192.168.1.10
```

Check the IP address on bsql-host2:
```bash
# On bsql-host2.01.me
ip addr show
# or
hostname -I
```

## Solution 2: Force Connection (If You Trust the Host)

```bash
# On bojpve
pvecm add bsql-host2.01.me --force
```

⚠️ This skips certificate verification. Only use if you trust the network is secure.

## Solution 3: Regenerate SSL Certificates (Proper Fix)

This ensures certificates match the actual hostnames:

```bash
# On bsql-host2.01.me (the master)

# Backup current certificates
cp /etc/pve/nodes/$(hostname)/pve-ssl.pem /etc/pve/nodes/$(hostname)/pve-ssl.pem.bak
cp /etc/pve/nodes/$(hostname)/pve-ssl.key /etc/pve/nodes/$(hostname)/pve-ssl.key.bak

# Check current hostname
hostname
hostname -f

# If hostname doesn't match bsql-host2.01.me, set it:
hostnamectl set-hostname bsql-host2.01.me

# Update /etc/hosts
nano /etc/hosts
# Make sure it has:
# 127.0.0.1       localhost
# <IP>            bsql-host2.01.me bsql-host2

# Regenerate the certificate
pvecm updatecerts --force

# Restart services
systemctl restart pveproxy
systemctl restart pvedaemon
```

Do the same on bojpve (host1):
```bash
# On bojpve
hostnamectl set-hostname bsql-host1.01.me

# Update /etc/hosts
nano /etc/hosts
# Add:
# <IP>            bsql-host1.01.me bsql-host1

# Regenerate certificates
pvecm updatecerts --force

# Restart services
systemctl restart pveproxy
systemctl restart pvedaemon
```

Then try joining again:
```bash
# On bojpve (host1)
pvecm add bsql-host2.01.me
```

## Solution 4: Check and Fix Hostname Resolution

Ensure both hosts can properly resolve each other:

```bash
# On both hosts, check /etc/hosts
cat /etc/hosts

# Should have entries like:
# 192.168.1.10    bsql-host2.01.me bsql-host2
# 192.168.1.11    bsql-host1.01.me bsql-host1 bojpve
# 192.168.1.12    bsql-storage.01.me bsql-storage

# Test resolution
ping -c 2 bsql-host2.01.me
ping -c 2 bsql-host1.01.me

# Test HTTPS connectivity
curl -k https://bsql-host2.01.me:8006
```

## Recommended Approach

I'd suggest this order:

1. **First, check what hostname the certificate was issued for:**
```bash
# On bsql-host2.01.me
openssl x509 -in /etc/pve/nodes/$(hostname)/pve-ssl.pem -noout -subject -ext subjectAltName
```

2. **Use IP address for joining (quickest):**
```bash
# On bojpve
pvecm add <IP-of-bsql-host2>
```

3. **After cluster is formed, fix the hostnames and regenerate certs:**
```bash
# On both nodes
pvecm updatecerts --force
systemctl restart pveproxy pvedaemon
```

## Verify After Joining

Once successful:
```bash
# Check cluster status
pvecm status
pvecm nodes

# Should show both nodes as members
```

Which approach would you like to try? I'd recommend starting with the IP address method (Solution 1) as it's the quickest way to get your cluster running.

---

### 👤 You

On PVE, how to create a VM with Ubuntu 24.04?

---

### 🤖 Cursor Assistant

I'll guide you through creating an Ubuntu 24.04 VM on Proxmox VE. Here are both the Web UI and CLI methods:

## Method 1: Using Web UI (Recommended for First Time)

### Step 1: Download Ubuntu 24.04 ISO

```bash
# SSH into your PVE host

# Navigate to ISO storage directory
cd /var/lib/vz/template/iso

# Download Ubuntu 24.04 LTS Server
wget https://releases.ubuntu.com/24.04/ubuntu-24.04-live-server-amd64.iso

# Or if you want the desktop version:
# wget https://releases.ubuntu.com/24.04/ubuntu-24.04-desktop-amd64.iso

# Verify download
ls -lh ubuntu-24.04*.iso
```

### Step 2: Create VM via Web UI

1. **Log into Proxmox Web UI**: `https://your-pve-host:8006`

2. **Click "Create VM"** (top right)

3. **General Tab:**
   - **Node**: Select your node
   - **VM ID**: 100 (or any available number)
   - **Name**: `ubuntu-2404` (or your choice)
   - Check **Start at boot** (optional)

4. **OS Tab:**
   - **ISO image**: Select `ubuntu-24.04-live-server-amd64.iso`
   - **Type**: Linux
   - **Version**: 6.x - 2.6 Kernel

5. **System Tab:**
   - **Graphic card**: Default (or SPICE for better performance)
   - **Machine**: q35
   - **BIOS**: OVMF (UEFI) - recommended for modern systems
   - **Add EFI Disk**: Yes (if using OVMF)
   - **SCSI Controller**: VirtIO SCSI single
   - **Qemu Agent**: ✓ Enable (recommended)

6. **Disks Tab:**
   - **Bus/Device**: SCSI, 0
   - **Storage**: Select your storage (local-lvm or nfs-storage)
   - **Disk size**: 32 GB (or as needed)
   - **Cache**: Write back (for better performance)
   - **Discard**: ✓ (if using SSD/thin provisioning)
   - **SSD emulation**: ✓ (if your storage is SSD)

7. **CPU Tab:**
   - **Cores**: 2 (or as needed)
   - **Type**: host (for best performance)

8. **Memory Tab:**
   - **Memory**: 2048 MB (2 GB minimum, 4096 MB recommended)
   - **Ballooning**: Enabled (default)

9. **Network Tab:**
   - **Bridge**: vmbr0
   - **Model**: VirtIO (paravirtualized)
   - **Firewall**: ✓ (optional)

10. **Confirm**: Review and click **Finish**

### Step 3: Install Ubuntu

1. **Start the VM**: Select VM → **Start**
2. **Open Console**: Click **Console** (or use noVNC)
3. **Follow Ubuntu installer:**
   - Select language
   - Update installer (if prompted)
   - Choose keyboard layout
   - Select network interface (should auto-configure)
   - No proxy (unless needed)
   - Default mirror
   - Storage: Use entire disk (default)
   - Enter your name, server name, username, password
   - **Install OpenSSH server**: ✓ (recommended)
   - No additional snaps (you can install later)
   - Wait for installation to complete
   - **Reboot**

### Step 4: Post-Installation Configuration

After first boot:

```bash
# SSH into your new VM
ssh username@vm-ip-address

# Update system
sudo apt update && sudo apt upgrade -y

# Install QEMU Guest Agent (important for PVE integration)
sudo apt install qemu-guest-agent -y
sudo systemctl enable qemu-guest-agent
sudo systemctl start qemu-guest-agent

# Install other useful tools
sudo apt install curl wget git htop net-tools -y

# Optional: Install cloud-init for better integration
sudo apt install cloud-init -y
```

On PVE host, verify guest agent is working:
```bash
qm agent <VMID> ping
```

---

## Method 2: Using CLI (Fast & Scriptable)

```bash
# On your PVE host

# Download ISO (if not already done)
cd /var/lib/vz/template/iso
wget https://releases.ubuntu.com/24.04/ubuntu-24.04-live-server-amd64.iso

# Create VM (VM ID 100)
qm create 100 \
  --name ubuntu-2404 \
  --memory 4096 \
  --cores 2 \
  --cpu host \
  --net0 virtio,bridge=vmbr0 \
  --scsihw virtio-scsi-single \
  --ostype l26

# Add EFI disk (for UEFI boot)
qm set 100 --efidisk0 local-lvm:1,efitype=4m,pre-enrolled-keys=1

# Add main disk (32GB)
qm set 100 --scsi0 local-lvm:32,cache=writeback,discard=on,ssd=1

# Attach ISO
qm set 100 --ide2 local:iso/ubuntu-24.04-live-server-amd64.iso,media=cdrom

# Set boot order
qm set 100 --boot order=scsi0;ide2

# Enable QEMU agent
qm set 100 --agent enabled=1

# Add serial console (optional, useful for troubleshooting)
qm set 100 --serial0 socket --vga serial0

# Set VM to start at boot (optional)
qm set 100 --onboot 1

# Start VM
qm start 100

# Open VNC console to complete installation
# Use web UI or:
qm terminal 100
```

After installation via console, follow Step 4 above for post-installation.

---

## Method 3: Cloud-Init Template (Advanced - For Multiple VMs)

Create a template for quick VM deployment:

```bash
# Download Ubuntu 24.04 cloud image
cd /var/lib/vz/template/iso
wget https://cloud-images.ubuntu.com/releases/24.04/release/ubuntu-24.04-server-cloudimg-amd64.img

# Create template VM
qm create 9000 \
  --name ubuntu-2404-template \
  --memory 2048 \
  --cores 2 \
  --cpu host \
  --net0 virtio,bridge=vmbr0 \
  --scsihw virtio-scsi-single \
  --ostype l26

# Import cloud image as disk
qm importdisk 9000 ubuntu-24.04-server-cloudimg-amd64.img local-lvm

# Attach disk to VM
qm set 9000 --scsi0 local-lvm:vm-9000-disk-0,cache=writeback,discard=on

# Add cloud-init drive
qm set 9000 --ide2 local-lvm:cloudinit

# Set boot disk
qm set 9000 --boot order=scsi0

# Add serial console
qm set 9000 --serial0 socket --vga serial0

# Enable QEMU agent
qm set 9000 --agent enabled=1

# Configure cloud-init defaults (optional)
qm set 9000 --ciuser ubuntu
qm set 9000 --cipassword <password>
qm set 9000 --sshkeys ~/.ssh/authorized_keys
qm set 9000 --ipconfig0 ip=dhcp

# Convert to template
qm template 9000

# Clone template to create new VMs instantly
qm clone 9000 100 --name ubuntu-vm1 --full
qm start 100
```

---

## Useful VM Management Commands

```bash
# List all VMs
qm list

# Check VM status
qm status 100

# Start/Stop/Reboot VM
qm start 100
qm stop 100
qm reboot 100

# Shutdown gracefully (requires guest agent)
qm shutdown 100

# Resize disk (add 10GB)
qm resize 100 scsi0 +10G

# Take snapshot
qm snapshot 100 pre-upgrade

# Clone VM
qm clone 100 101 --name ubuntu-clone

# Migrate to another node (if clustered)
qm migrate 100 bsql-host2 --online

# Delete VM
qm destroy 100
```

---

## Performance Optimization Tips

After installation, consider these optimizations:

1. **Enable virtio drivers** (already done if you followed above)

2. **Disable swap if using SSDs:**
```bash
sudo swapoff -a
sudo sed -i '/ swap / s/^/#/' /etc/fstab
```

3. **Enable fstrim for SSDs:**
```bash
sudo systemctl enable fstrim.timer
```

4. **Install performance tools:**
```bash
sudo apt install linux-tools-generic tuned -y
sudo tuned-adm profile virtual-guest
```

Which method would you like to use? The Web UI is best for learning and one-off VMs, while CLI is great for automation and multiple VMs.

---

### 👤 You

I want to migrate a VM from another cloud provider to my new PVE cluster, by rsyncing the rootfs from the existing VM to a new PVE VM. The existing VM is Debian GNU/Linux 11 (bullseye). How to create the VM, and how to perform the migration?

---

### 🤖 Cursor Assistant

I'll guide you through migrating a Debian 11 VM from another cloud provider to your PVE cluster using rsync. This is a manual P2V/V2V migration process.

## Overview

The process involves:
1. Creating a target VM on PVE with similar specs
2. Preparing both VMs for migration
3. Rsync-ing the filesystem
4. Fixing boot configuration, fstab, and network settings
5. Installing proper drivers and cleaning up cloud-init

## Step 1: Analyze Source VM

On your existing cloud VM:

```bash
# Check current system info
uname -a
cat /etc/debian_version
lsblk
df -h

# Check partition layout
fdisk -l

# Check filesystem types
mount | grep "^/dev"

# Check if UEFI or BIOS
[ -d /sys/firmware/efi ] && echo "UEFI" || echo "BIOS"

# Note network interface names
ip addr show

# Check what's installed
dpkg -l | grep -E "cloud-init|qemu|virtio"
```

Make note of:
- Total disk size needed
- Whether it's UEFI or BIOS
- Network configuration method

## Step 2: Create Target VM on PVE

```bash
# On PVE host
# Create VM (adjust specs to match your source VM)
VMID=101
VM_NAME="migrated-debian11"
DISK_SIZE=50G  # Adjust based on source VM
MEMORY=4096    # Adjust as needed
CORES=2        # Adjust as needed

# Create base VM
qm create ${VMID} \
  --name ${VM_NAME} \
  --memory ${MEMORY} \
  --cores ${CORES} \
  --cpu host \
  --net0 virtio,bridge=vmbr0 \
  --scsihw virtio-scsi-single \
  --ostype l26

# If source is UEFI, add EFI disk:
qm set ${VMID} --efidisk0 local-lvm:1,efitype=4m,pre-enrolled-keys=1

# If source is BIOS (legacy), skip EFI and set BIOS:
# qm set ${VMID} --bios seabios

# Add main disk
qm set ${VMID} --scsi0 local-lvm:${DISK_SIZE},cache=writeback,discard=on

# Enable QEMU agent (we'll install it later)
qm set ${VMID} --agent enabled=1

# Add serial console for troubleshooting
qm set ${VMID} --serial0 socket --vga serial0

# Don't start it yet - we need to prepare it
```

## Step 3: Prepare Target VM with Rescue System

We'll use a Debian live ISO to boot and prepare the target disk:

```bash
# Download Debian live ISO
cd /var/lib/vz/template/iso
wget https://cdimage.debian.org/debian-cd/current-live/amd64/iso-hybrid/debian-live-11.9.0-amd64-standard.iso

# Attach to VM
qm set ${VMID} --ide2 local:iso/debian-live-11.9.0-amd64-standard.iso,media=cdrom

# Set boot order to boot from CD first
qm set ${VMID} --boot order=ide2;scsi0

# Start VM
qm start ${VMID}
```

## Step 4: Partition and Format Target Disk

Access the VM console and boot into the live system:

```bash
# In the VM console (via PVE web UI or qm terminal)
# Once booted into Debian live, become root
sudo -i

# Identify the disk
lsblk
# Should show /dev/sda or /dev/vda (virtio)

# For BIOS boot:
# Create partitions (example for a simple layout)
parted /dev/sda --script -- \
  mklabel msdos \
  mkpart primary ext4 1MiB 100%

# Format
mkfs.ext4 -L rootfs /dev/sda1

# For UEFI boot:
# Create GPT partitions
parted /dev/sda --script -- \
  mklabel gpt \
  mkpart ESP fat32 1MiB 512MiB \
  set 1 esp on \
  mkpart primary ext4 512MiB 100%

# Format EFI partition
mkfs.fat -F32 /dev/sda1

# Format root partition
mkfs.ext4 -L rootfs /dev/sda2

# Mount target filesystem
mkdir -p /mnt/target

# For BIOS:
mount /dev/sda1 /mnt/target

# For UEFI:
mount /dev/sda2 /mnt/target
mkdir -p /mnt/target/boot/efi
mount /dev/sda1 /mnt/target/boot/efi

# Create necessary directories for rsync
mkdir -p /mnt/target/{dev,proc,sys,run}
```

## Step 5: Rsync from Source to Target

On the **target VM** (still in live system), establish SSH access and rsync:

```bash
# In target VM live system
# Setup network (should auto-configure via DHCP)
dhclient

# Check IP
ip addr show

# Install rsync if not present
apt update
apt install rsync openssh-server -y

# Set root password temporarily
passwd

# Start SSH
systemctl start ssh
```

On the **source VM** (or from anywhere with access to both):

```bash
# From source VM, rsync to target
# Replace TARGET_IP with the IP of your target VM
TARGET_IP="x.x.x.x"

rsync -aAXHv --progress \
  --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found","/swapfile"} \
  / root@${TARGET_IP}:/mnt/target/

# This will take some time depending on data size
```

**Alternative method** (if source can't reach target directly):

```bash
# From a machine that can reach both source and target
SOURCE_IP="source.vm.ip"
TARGET_IP="target.vm.ip"

# Rsync via intermediate host
rsync -aAXHv --progress \
  --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found","/swapfile"} \
  root@${SOURCE_IP}:/ root@${TARGET_IP}:/mnt/target/
```

## Step 6: Fix Boot Configuration on Target

Back in the **target VM console** (live system):

```bash
# Chroot into the migrated system
mount --bind /dev /mnt/target/dev
mount --bind /dev/pts /mnt/target/dev/pts
mount --bind /proc /mnt/target/proc
mount --bind /sys /mnt/target/sys
mount --bind /run /mnt/target/run

chroot /mnt/target /bin/bash

# Now we're in the migrated system
export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

# Update /etc/fstab
# First, get UUID of root partition
blkid

# Edit fstab
nano /etc/fstab

# For BIOS setup, replace with:
# UUID=<your-root-uuid>  /     ext4  errors=remount-ro  0  1

# For UEFI setup:
# UUID=<your-root-uuid>  /               ext4  errors=remount-ro  0  1
# UUID=<your-efi-uuid>   /boot/efi       vfat  umask=0077         0  1

# Remove any cloud-specific entries (swap, ephemeral disks, etc.)

# Install/update GRUB
# First, install necessary packages
apt update
apt install grub-pc linux-image-amd64 -y  # For BIOS
# OR for UEFI:
# apt install grub-efi-amd64 linux-image-amd64 -y

# Install GRUB bootloader
# For BIOS:
grub-install /dev/sda

# For UEFI:
# grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=debian

# Update GRUB configuration
update-grub

# Install virtio drivers and QEMU guest agent
apt install qemu-guest-agent -y
systemctl enable qemu-guest-agent

# Ensure virtio modules are in initramfs
echo "virtio_blk" >> /etc/initramfs-tools/modules
echo "virtio_pci" >> /etc/initramfs-tools/modules
echo "virtio_net" >> /etc/initramfs-tools/modules
echo "virtio_scsi" >> /etc/initramfs-tools/modules

# Regenerate initramfs
update-initramfs -u -k all
```

## Step 7: Fix Network Configuration

```bash
# Still in chroot

# Check current network config
cat /etc/network/interfaces
ls /etc/netplan/  # if using netplan

# For traditional Debian network configuration:
nano /etc/network/interfaces

# Replace with (for DHCP):
auto lo
iface lo inet loopback

auto ens18
iface ens18 inet dhcp

# Note: PVE usually names the first virtio NIC as ens18
# If you want static IP, use:
# auto ens18
# iface ens18 inet static
#     address 192.168.1.100
#     netmask 255.255.255.0
#     gateway 192.168.1.1
#     dns-nameservers 8.8.8.8 8.8.4.4

# Update hostname if needed
hostnamectl set-hostname your-new-hostname
nano /etc/hosts

# Remove cloud-init if present (prevents it from overwriting configs)
apt purge cloud-init -y
rm -rf /etc/cloud/ /var/lib/cloud/

# Clean up cloud-specific configurations
rm -f /etc/netplan/50-cloud-init.yaml
```

## Step 8: Final Cleanup and Exit

```bash
# Still in chroot

# Update package lists
apt update
apt upgrade -y

# Clean up
apt autoremove -y
apt clean

# Set root password (if needed)
passwd

# Exit chroot
exit

# Unmount everything
umount /mnt/target/dev/pts
umount /mnt/target/dev
umount /mnt/target/proc
umount /mnt/target/sys
umount /mnt/target/run

# For UEFI:
umount /mnt/target/boot/efi

umount /mnt/target

# Shutdown the live system
poweroff
```

## Step 9: Prepare VM for First Boot

Back on the **PVE host**:

```bash
# Remove the CD from boot order
qm set ${VMID} --boot order=scsi0

# Remove CD drive (optional)
qm set ${VMID} --delete ide2

# Start the VM
qm start ${VMID}

# Watch the boot process
qm terminal ${VMID}
# Or use the web console
```

## Step 10: Post-Migration Verification

Once the VM boots successfully, SSH into it:

```bash
# Check system info
uname -a
df -h
lsblk
ip addr show

# Verify QEMU guest agent is running
systemctl status qemu-guest-agent

# Update system
apt update && apt upgrade -y

# Check for any issues
journalctl -xb | grep -i error

# Install additional useful packages
apt install htop tmux vim curl wget -y
```

## Troubleshooting

### If VM doesn't boot:

1. **Boot into rescue mode again:**
```bash
# Reattach live ISO
qm set ${VMID} --ide2 local:iso/debian-live-11.9.0-amd64-standard.iso,media=cdrom
qm set ${VMID} --boot order=ide2;scsi0
qm start ${VMID}

# Mount and chroot again
sudo -i
mount /dev/sda2 /mnt/target  # or sda1 for BIOS
mount /dev/sda1 /mnt/target/boot/efi  # if UEFI
mount --bind /dev /mnt/target/dev
mount --bind /proc /mnt/target/proc
mount --bind /sys /mnt/target/sys
chroot /mnt/target

# Check logs
journalctl -xb | tail -100

# Reinstall GRUB
grub-install /dev/sda
update-grub
update-initramfs -u -k all
```

2. **Check serial console output:**
```bash
# On PVE host
qm terminal ${VMID}
```

3. **Common issues:**
- **Wrong disk in fstab**: Fix UUIDs in `/etc/fstab`
- **Missing virtio drivers**: Regenerate initramfs with virtio modules
- **Network not coming up**: Check interface names changed (use `ip link` to see actual names)
- **GRUB errors**: Reinstall grub on correct disk

### Network interface name mismatch:

```bash
# In the VM, check actual interface names
ip link show

# If different from config, either:
# Option 1: Use predictable names (ens18, etc.)
# Already configured above

# Option 2: Use old-style names (eth0)
# Add to GRUB:
nano /etc/default/grub
# Add: GRUB_CMDLINE_LINUX="net.ifnames=0 biosdevname=0"
update-grub
reboot
```

## Performance Comparison

After migration, you might want to benchmark:

```bash
# Disk I/O test
dd if=/dev/zero of=/tmp/testfile bs=1G count=1 oflag=direct
rm /tmp/testfile

# Install sysbench
apt install sysbench -y

# CPU test
sysbench cpu --cpu-max-prime=20000 run

# Memory test
sysbench memory run
```

## Script for Easier Migration

Here's a helper script you can use on the target (save as `prepare-migration.sh`):

```bash
#!/bin/bash
# Run this in the live system after partitioning

TARGET_MOUNT="/mnt/target"
SOURCE_USER="root"
SOURCE_IP="source.vm.ip.here"

# Mount target
mount /dev/sda1 $TARGET_MOUNT  # Adjust partition

# Rsync from source
rsync -aAXHv --progress \
  --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found","/swapfile"} \
  ${SOURCE_USER}@${SOURCE_IP}:/ ${TARGET_MOUNT}/

echo "Rsync complete. Now run post-migration-fixes.sh"
```

Would you like me to clarify any of these steps or provide additional scripts for automation?

---

### 👤 You

Would should I do if there is another VM on public cloud to migrate, which is Ubuntu 24.04 LTS?

---

### 🤖 Cursor Assistant

Great question! Migrating Ubuntu 24.04 LTS is very similar to Debian 11, but there are some Ubuntu-specific differences to handle. Here's what you need to adjust:

## Key Differences for Ubuntu 24.04

### 1. Use Ubuntu Live ISO Instead

```bash
# On PVE host, download Ubuntu 24.04 live ISO
cd /var/lib/vz/template/iso
wget https://releases.ubuntu.com/24.04/ubuntu-24.04-live-server-amd64.iso

# Attach to your new VM
VMID=102  # Use different VM ID
qm set ${VMID} --ide2 local:iso/ubuntu-24.04-live-server-amd64.iso,media=cdrom
```

### 2. Network Configuration - Use Netplan

Ubuntu uses **Netplan** instead of `/etc/network/interfaces`. During the chroot phase:

```bash
# In chroot (after rsync, in Step 6)

# Remove cloud-init netplan config
rm -f /etc/netplan/50-cloud-init.yaml
rm -f /etc/netplan/*-cloud-init.yaml

# Create new netplan config
nano /etc/netplan/01-netcfg.yaml

# For DHCP:
network:
  version: 2
  renderer: networkd
  ethernets:
    ens18:
      dhcp4: true
      dhcp6: false

# For static IP:
network:
  version: 2
  renderer: networkd
  ethernets:
    ens18:
      addresses:
        - 192.168.1.100/24
      routes:
        - to: default
          via: 192.168.1.1
      nameservers:
        addresses:
          - 8.8.8.8
          - 8.8.4.4

# Set correct permissions
chmod 600 /etc/netplan/01-netcfg.yaml

# Test the configuration (optional, won't apply in chroot)
netplan generate
```

### 3. Handle Snap Packages

Ubuntu 24.04 uses snap extensively. During chroot:

```bash
# In chroot

# Check what snaps are installed
snap list

# Snaps should work fine after migration, but if you have issues:
# Refresh all snaps after first boot
# snap refresh

# Or if you prefer to avoid snaps entirely:
# (This is optional - snaps usually work fine)
# apt purge snapd -y
# apt-mark hold snapd
```

### 4. Ubuntu-Specific GRUB Installation

```bash
# In chroot

# Update package lists
apt update

# Install necessary packages for Ubuntu
apt install --reinstall linux-image-generic linux-headers-generic -y

# For BIOS boot:
apt install grub-pc -y
grub-install /dev/sda
update-grub

# For UEFI boot (more common in Ubuntu 24.04):
apt install grub-efi-amd64 grub-efi-amd64-signed shim-signed -y
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=ubuntu --recheck
update-grub

# Ensure virtio drivers
apt install linux-modules-extra-$(uname -r) -y

# Update initramfs
update-initramfs -u -k all
```

### 5. Cloud-Init Cleanup (More Thorough for Ubuntu)

Ubuntu's cloud-init is more integrated, so cleanup is important:

```bash
# In chroot

# Disable cloud-init permanently
echo 'datasource_list: [ None ]' | tee /etc/cloud/cloud.cfg.d/90_dpkg.cfg

# Or completely remove it
apt purge cloud-init -y
rm -rf /etc/cloud/ /var/lib/cloud/

# Remove cloud-init from boot
systemctl disable cloud-init.service
systemctl disable cloud-init-local.service
systemctl disable cloud-config.service
systemctl disable cloud-final.service

# Clean up cloud-init artifacts
rm -f /etc/netplan/*-cloud-init.yaml
rm -f /etc/machine-id
systemd-machine-id-setup
```

### 6. Ubuntu-Specific System Cleanup

```bash
# In chroot

# Remove cloud provider specific packages (if any)
apt purge cloud-initramfs-* cloud-guest-utils -y

# Remove old kernels (keep current)
apt autoremove --purge -y

# Install QEMU guest agent
apt install qemu-guest-agent -y
systemctl enable qemu-guest-agent

# Update package cache
apt update
apt upgrade -y

# Clean up
apt clean
```

## Complete Ubuntu 24.04 Migration Script

Here's a streamlined process focusing on Ubuntu-specific steps:

### Modified Step 6 for Ubuntu (Chroot Configuration)

```bash
# After rsync completes, in the live system:

# Chroot into migrated system
mount --bind /dev /mnt/target/dev
mount --bind /dev/pts /mnt/target/dev/pts
mount --bind /proc /mnt/target/proc
mount --bind /sys /mnt/target/sys
mount --bind /run /mnt/target/run

chroot /mnt/target /bin/bash
export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

# 1. Update fstab
ROOT_UUID=$(blkid -s UUID -o value /dev/sda2)  # or /dev/sda1 for BIOS
EFI_UUID=$(blkid -s UUID -o value /dev/sda1)   # if UEFI

cat > /etc/fstab << EOF
# /etc/fstab: static file system information
UUID=${ROOT_UUID}  /          ext4  errors=remount-ro  0  1
EOF

# Add EFI line if UEFI:
if [ -d /sys/firmware/efi ]; then
    echo "UUID=${EFI_UUID}  /boot/efi  vfat  umask=0077  0  1" >> /etc/fstab
fi

# 2. Install/update kernel and GRUB
apt update
apt install --reinstall linux-image-generic linux-headers-generic -y

# For UEFI (most common):
apt install grub-efi-amd64 grub-efi-amd64-signed shim-signed -y
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=ubuntu --recheck

# For BIOS:
# apt install grub-pc -y
# grub-install /dev/sda

update-grub

# 3. Ensure virtio modules
echo "virtio_blk" >> /etc/initramfs-tools/modules
echo "virtio_pci" >> /etc/initramfs-tools/modules
echo "virtio_net" >> /etc/initramfs-tools/modules
echo "virtio_scsi" >> /etc/initramfs-tools/modules

update-initramfs -u -k all

# 4. Install QEMU guest agent
apt install qemu-guest-agent -y
systemctl enable qemu-guest-agent

# 5. Configure Netplan for networking
rm -f /etc/netplan/*-cloud-init.yaml

cat > /etc/netplan/01-netcfg.yaml << 'EOF'
network:
  version: 2
  renderer: networkd
  ethernets:
    ens18:
      dhcp4: true
      dhcp6: false
EOF

chmod 600 /etc/netplan/01-netcfg.yaml

# 6. Disable/remove cloud-init
echo 'datasource_list: [ None ]' > /etc/cloud/cloud.cfg.d/90_dpkg.cfg
systemctl disable cloud-init.service 2>/dev/null || true
systemctl disable cloud-init-local.service 2>/dev/null || true
systemctl disable cloud-config.service 2>/dev/null || true
systemctl disable cloud-final.service 2>/dev/null || true

# Or completely remove:
# apt purge cloud-init -y
# rm -rf /etc/cloud/ /var/lib/cloud/

# 7. Update hostname
hostnamectl set-hostname your-new-hostname
echo "your-new-hostname" > /etc/hostname

# Update /etc/hosts
cat > /etc/hosts << EOF
127.0.0.1       localhost
127.0.1.1       your-new-hostname

# The following lines are desirable for IPv6 capable hosts
::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
EOF

# 8. Regenerate machine-id
rm -f /etc/machine-id /var/lib/dbus/machine-id
systemd-machine-id-setup

# 9. Set root password (if needed)
passwd

# 10. Final updates
apt update
apt upgrade -y
apt autoremove --purge -y
apt clean

# 11. Exit chroot
exit
```

## Ubuntu 24.04 Specific Troubleshooting

### Issue: Network not working after boot

```bash
# Boot into rescue, mount and chroot
# Check netplan syntax
netplan generate

# Check actual interface name
ip link show

# If interface name is different, update netplan:
# Replace ens18 with actual interface name (e.g., enp6s18, ens3, etc.)

# Test netplan
netplan try

# Apply
netplan apply
```

### Issue: Snap services failing

```bash
# After first boot
sudo snap refresh
sudo systemctl restart snapd

# Check snap status
snap list
snap changes
```

### Issue: systemd-resolved not working

```bash
# Check resolved status
systemctl status systemd-resolved

# Restart if needed
systemctl restart systemd-resolved

# Check DNS
resolvectl status

# If needed, manually set DNS
nano /etc/systemd/resolved.conf
# Add: DNS=8.8.8.8 8.8.4.4
systemctl restart systemd-resolved
```

### Issue: AppArmor profiles causing issues

```bash
# Check AppArmor status
aa-status

# If you see errors related to old paths:
# Reload all profiles
systemctl reload apparmor

# Or disable temporarily for troubleshooting
systemctl stop apparmor
systemctl disable apparmor
```

## Automation Script for Ubuntu 24.04

Create `ubuntu-migration-post-rsync.sh` to run inside chroot:

```bash
#!/bin/bash
set -e

echo "Starting Ubuntu 24.04 post-migration configuration..."

# Detect boot mode
if [ -d /sys/firmware/efi ]; then
    BOOT_MODE="UEFI"
    ROOT_PART="/dev/sda2"
    EFI_PART="/dev/sda1"
else
    BOOT_MODE="BIOS"
    ROOT_PART="/dev/sda1"
fi

echo "Detected boot mode: ${BOOT_MODE}"

# Update fstab
echo "Updating fstab..."
ROOT_UUID=$(blkid -s UUID -o value ${ROOT_PART})
cat > /etc/fstab << EOF
UUID=${ROOT_UUID}  /  ext4  errors=remount-ro  0  1
EOF

if [ "${BOOT_MODE}" = "UEFI" ]; then
    EFI_UUID=$(blkid -s UUID -o value ${EFI_PART})
    echo "UUID=${EFI_UUID}  /boot/efi  vfat  umask=0077  0  1" >> /etc/fstab
fi

# Update packages
echo "Updating packages..."
apt update
apt install --reinstall -y linux-image-generic linux-headers-generic

# Install GRUB
echo "Installing GRUB..."
if [ "${BOOT_MODE}" = "UEFI" ]; then
    apt install -y grub-efi-amd64 grub-efi-amd64-signed shim-signed
    grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=ubuntu --recheck
else
    apt install -y grub-pc
    grub-install /dev/sda
fi
update-grub

# Configure virtio
echo "Configuring virtio drivers..."
cat >> /etc/initramfs-tools/modules << EOF
virtio_blk
virtio_pci
virtio_net
virtio_scsi
EOF
update-initramfs -u -k all

# Install guest agent
echo "Installing QEMU guest agent..."
apt install -y qemu-guest-agent
systemctl enable qemu-guest-agent

# Configure netplan
echo "Configuring netplan..."
rm -f /etc/netplan/*-cloud-init.yaml
cat > /etc/netplan/01-netcfg.yaml << 'EOF'
network:
  version: 2
  renderer: networkd
  ethernets:
    ens18:
      dhcp4: true
      dhcp6: false
EOF
chmod 600 /etc/netplan/01-netcfg.yaml

# Disable cloud-init
echo "Disabling cloud-init..."
echo 'datasource_list: [ None ]' > /etc/cloud/cloud.cfg.d/90_dpkg.cfg
systemctl disable cloud-init.service 2>/dev/null || true
systemctl disable cloud-init-local.service 2>/dev/null || true
systemctl disable cloud-config.service 2>/dev/null || true
systemctl disable cloud-final.service 2>/dev/null || true

# Clean up
echo "Cleaning up..."
rm -f /etc/machine-id /var/lib/dbus/machine-id
systemd-machine-id-setup
apt autoremove --purge -y
apt clean

echo "Post-migration configuration complete!"
echo "Set root password before exiting if needed"
```

Usage:
```bash
# In chroot
chmod +x /ubuntu-migration-post-rsync.sh
./ubuntu-migration-post-rsync.sh
passwd  # Set root password
exit
```

## Summary of Key Ubuntu 24.04 Differences

| Aspect | Debian 11 | Ubuntu 24.04 |
|--------|-----------|--------------|
| Network Config | `/etc/network/interfaces` | Netplan (`/etc/netplan/`) |
| Cloud-init | Less integrated | Deeply integrated, needs thorough cleanup |
| Package Manager | Pure APT | APT + Snap |
| GRUB Package | `grub-pc` | `grub-efi-amd64-signed` + `shim-signed` for UEFI |
| Init System | systemd | systemd (same) |
| Default Shell | bash | bash (same) |
| Kernel Naming | `linux-image-amd64` | `linux-image-generic` |

The main differences are **Netplan** and **cloud-init cleanup**. Everything else follows the same process as Debian 11!

Would you like me to provide a complete step-by-step checklist for Ubuntu 24.04 migration, or help with any specific aspect?

---

### 👤 You

If the physical host has 32 cores and 128G mem, in PVE, can we create twos VM each with 32 cores and 128G mem, and let them contend on the cores?

---

### 🤖 Cursor Assistant

Excellent question! Yes, you can overcommit resources in Proxmox VE, but **CPU** and **memory** behave very differently. Let me explain:

## Short Answer

- **CPU**: ✅ **Yes**, you can easily overcommit. Creating 2 VMs with 32 cores each on a 32-core host is common and safe.
- **Memory**: ⚠️ **Risky**. Creating 2 VMs with 128GB each on a 128GB host will likely cause serious problems.

## CPU Overcommitment (Safe & Common)

### How It Works

```bash
# Physical host: 32 cores
# You can create:
VM1: 32 vCPUs
VM2: 32 vCPUs
# Total: 64 vCPUs on 32 physical cores
# Overcommit ratio: 2:1

# This is FINE because:
# - Most VMs don't use 100% CPU all the time
# - Linux scheduler efficiently time-slices CPU
# - Hypervisor manages CPU scheduling transparently
```

### Creating CPU-Overcommitted VMs

```bash
# Create first VM with 32 cores
qm create 100 \
  --name vm1-cpu32 \
  --cores 32 \
  --cpu host \
  --memory 60000

# Create second VM with 32 cores
qm create 101 \
  --name vm2-cpu32 \
  --cores 32 \
  --cpu host \
  --memory 60000

# Both can run simultaneously without issues
qm start 100
qm start 101
```

### CPU Overcommit Best Practices

**Typical overcommit ratios:**
- **Conservative**: 2:1 (64 vCPUs on 32 cores) - Very safe
- **Moderate**: 4:1 (128 vCPUs on 32 cores) - Usually fine
- **Aggressive**: 8:1 (256 vCPUs on 32 cores) - For light workloads

**Configure CPU limits if needed:**
```bash
# Set CPU units (relative weight, default is 1024)
qm set 100 --cpuunits 2048  # Give VM1 more priority
qm set 101 --cpuunits 1024  # Give VM2 normal priority

# Set CPU limit (percentage of total CPU time)
qm set 100 --cpulimit 16    # Limit VM1 to 16 cores worth
qm set 101 --cpulimit 16    # Limit VM2 to 16 cores worth
```

## Memory Overcommitment (Risky!)

### The Problem

```bash
# Physical host: 128GB RAM
# If you create:
VM1: 128GB RAM
VM2: 128GB RAM
# Total: 256GB on 128GB physical RAM

# This will FAIL because:
# - RAM can't be overcommitted like CPU
# - If both VMs try to use their full allocation, system will crash/OOM
# - Hypervisor needs ~2-4GB for itself
# - Swapping is extremely slow
```

### What Happens?

1. **Best case**: VMs don't use full allocation, things work
2. **Typical case**: System runs out of memory, triggers OOM killer
3. **Worst case**: Host crashes, both VMs die

### Safer Memory Approaches

#### Option 1: Split Memory Conservatively (Recommended)

```bash
# Leave headroom for host (4-8GB)
# Split remaining RAM between VMs

# Host: 128GB total
# Reserve: 4GB for PVE host
# Available: 124GB for VMs

# Conservative split:
qm set 100 --memory 60000  # 60GB for VM1
qm set 101 --memory 60000  # 60GB for VM2
# Total: 120GB (leaves 8GB buffer)
```

#### Option 2: Use Memory Ballooning (Moderate Risk)

Enable dynamic memory allocation:

```bash
# Allocate more than physical, but set minimum
qm set 100 --memory 80000 --balloon 40000
qm set 101 --memory 80000 --balloon 40000

# This means:
# - VM sees 80GB
# - Can balloon down to 40GB under pressure
# - Host can reclaim memory dynamically
```

Configure ballooning on VMs:
```bash
# In each VM, ensure balloon driver is loaded
lsmod | grep virtio_balloon

# If not present, load it
modprobe virtio_balloon
echo "virtio_balloon" >> /etc/modules
```

#### Option 3: Enable KSM (Kernel Same-page Merging)

Share identical memory pages between VMs:

```bash
# On PVE host
systemctl enable ksmtuned
systemctl start ksmtuned

# Check KSM status
cat /sys/kernel/mm/ksm/pages_sharing
cat /sys/kernel/mm/ksm/pages_shared

# Manual KSM configuration
echo 1 > /sys/kernel/mm/ksm/run
echo 1000 > /sys/kernel/mm/ksm/pages_to_scan
echo 20 > /sys/kernel/mm/ksm/sleep_millisecs
```

KSM is effective when:
- Running multiple similar VMs (same OS)
- VMs have lots of duplicate pages
- Can save 20-40% memory in some scenarios

#### Option 4: Use Swap (Last Resort)

```bash
# On PVE host, add swap
# Check current swap
swapon --show

# If no swap, create swap file (32GB example)
fallocate -l 32G /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile

# Make permanent
echo '/swapfile none swap sw 0 0' >> /etc/fstab

# Configure swap behavior (prefer RAM)
sysctl vm.swappiness=10
echo "vm.swappiness=10" >> /etc/sysctl.conf
```

⚠️ **Warning**: Swap is 1000x slower than RAM. This is emergency overflow, not a real solution.

## Recommended Configuration for Your Hardware

For a **32-core, 128GB** host:

### Scenario 1: Two Production VMs (Balanced)

```bash
# VM 1: Web application server
qm create 100 --name webapp \
  --cores 16 \
  --cpu host \
  --memory 56000 \
  --balloon 28000

# VM 2: Database server  
qm create 101 --name database \
  --cores 16 \
  --cpu host \
  --memory 60000 \
  --balloon 30000

# Total: 32 cores, 116GB RAM
# Leaves: 0 core overcommit, 12GB for host
```

### Scenario 2: Maximize Utilization (Aggressive)

```bash
# VM 1: Compute workload
qm create 100 --name compute1 \
  --cores 28 \
  --cpu host \
  --cpulimit 14 \
  --memory 60000 \
  --balloon 30000

# VM 2: Compute workload
qm create 101 --name compute2 \
  --cores 28 \
  --cpu host \
  --cpulimit 14 \
  --memory 60000 \
  --balloon 30000

# Total: 56 vCPUs on 32 cores (1.75:1 overcommit)
# Total: 120GB RAM (safe with ballooning)
# Each VM limited to 14 physical cores worth
```

### Scenario 3: Maximum Overcommit (Your Original Question)

```bash
# VM 1: Full allocation
qm create 100 --name vm1 \
  --cores 32 \
  --cpu host \
  --memory 60000 \
  --balloon 30000 \
  --cpuunits 1024

# VM 2: Full allocation
qm create 101 --name vm2 \
  --cores 32 \
  --cpu host \
  --memory 60000 \
  --balloon 30000 \
  --cpuunits 1024

# This gives each VM:
# - 32 vCPUs (will share 32 physical cores via scheduler)
# - 60GB RAM (balloonable to 30GB minimum)
# - Safe because memory doesn't exceed physical

# If you REALLY want 128GB per VM:
# DON'T DO THIS unless you're sure VMs won't use full allocation:
qm set 100 --memory 128000 --balloon 32000
qm set 101 --memory 128000 --balloon 32000
# This is dangerous!
```

## Monitoring Resource Contention

### Check CPU Usage

```bash
# On PVE host
top
htop

# Per-VM CPU usage
qm status 100 --verbose
qm monitor 100
# In monitor: info cpus

# Check CPU wait/steal time (in VM)
# High steal% means CPU contention
vmstat 1
```

### Check Memory Pressure

```bash
# On PVE host
free -h
cat /proc/meminfo

# Check if ballooning is active
qm status 100 --verbose | grep balloon

# Check OOM events
dmesg | grep -i "out of memory"
journalctl -k | grep -i oom

# In VM, check memory pressure
cat /proc/pressure/memory
```

### Real-time Monitoring

```bash
# Install monitoring
apt install sysstat atop

# Watch in real-time
watch -n 1 'qm status 100; qm status 101; free -h'

# Better: Use Proxmox web UI
# Shows real-time graphs for CPU, memory, disk, network
```

## Advanced: CPU Pinning (No Contention)

If you want to **avoid** CPU contention entirely, pin VMs to specific cores:

```bash
# Pin VM1 to cores 0-15
qm set 100 --cpuunits 1024 --vcpus 16 --affinity 0-15

# Pin VM2 to cores 16-31
qm set 101 --cpuunits 1024 --vcpus 16 --affinity 16-31

# Now VMs don't contend - each has dedicated cores
# But you lose flexibility and average utilization may drop
```

Check CPU topology first:
```bash
# On PVE host
lscpu | grep -E "^CPU\(s\)|Socket|Core|Thread"
numactl --hardware

# Pin to same NUMA node if possible for best performance
```

## Summary Table

| Configuration | CPU | Memory | Safety | Best For |
|---------------|-----|--------|--------|----------|
| 2×16c, 2×60GB | No overcommit | Safe | ✅ Very Safe | Production |
| 2×32c, 2×60GB | 2:1 overcommit | Safe | ✅ Safe | General use |
| 2×32c, 2×80GB w/ balloon | 2:1 overcommit | Moderate | ⚠️ OK | Dynamic workloads |
| 2×32c, 2×128GB | 2:1 overcommit | Dangerous | ❌ Risky | Don't do this |

## The Answer to Your Exact Question

**Can you create 2 VMs each with 32 cores and 128GB mem?**

- **Technically**: Yes, Proxmox will let you do it
- **CPU (32c×2)**: ✅ Perfectly fine, will work well
- **Memory (128GB×2)**: ❌ **Don't do it** - system will crash when both VMs use their allocation

**Recommended instead**:
```bash
# 2 VMs with 32 cores each, 60GB RAM each (with ballooning)
qm create 100 --cores 32 --cpu host --memory 60000 --balloon 30000
qm create 101 --cores 32 --cpu host --memory 60000 --balloon 30000
```

This gives you CPU overcommit (which is good) without dangerous memory overcommit.

Would you like help setting up monitoring to track resource contention, or configuring specific overcommit ratios for your workload?

---

### 👤 You

root@bojie2:/var/lib/vz/template/iso# qm set 100 --scsi0 local-lvm:1024G,cache=writeback,discard=on
unable to parse lvm volume name '1024G'

---

### 🤖 Cursor Assistant

The syntax error is in how you're specifying the disk size. Remove the `G` suffix - Proxmox expects the size as a plain number (in GB by default).

## Correct Syntax

```bash
# Correct: Size without 'G' suffix
qm set 100 --scsi0 local-lvm:1024,cache=writeback,discard=on

# The number is interpreted as GB by default
```

## Common Disk Size Formats

```bash
# All of these work:
qm set 100 --scsi0 local-lvm:32      # 32GB
qm set 100 --scsi0 local-lvm:1024    # 1024GB (1TB)
qm set 100 --scsi0 local-lvm:100     # 100GB

# With additional options:
qm set 100 --scsi0 local-lvm:500,cache=writeback,discard=on,ssd=1
```

## If Disk Already Exists

If the disk already exists and you want to **resize** it, use `qm resize`:

```bash
# Add 512GB to existing disk
qm resize 100 scsi0 +512G

# Or set to specific size (note: can only grow, not shrink)
qm resize 100 scsi0 1024G
```

## Full Example: Create VM with 1TB Disk

```bash
# Create VM
qm create 100 \
  --name my-vm \
  --memory 4096 \
  --cores 4 \
  --cpu host \
  --net0 virtio,bridge=vmbr0 \
  --scsihw virtio-scsi-single \
  --ostype l26

# Add 1TB disk (note: no 'G' suffix)
qm set 100 --scsi0 local-lvm:1024,cache=writeback,discard=on,ssd=1

# Verify
qm config 100
```

## Check Available Storage

Before creating large disks:

```bash
# Check storage capacity
pvesm status

# Check specific storage
pvesm status local-lvm

# Example output:
# Name         Type     Status           Total            Used       Available        %
# local-lvm    lvmthin  active      3166281728       105906176      3060375552    3.34%
```

## Alternative Storage Specifications

If you have multiple storage backends:

```bash
# Using different storage
qm set 100 --scsi0 nfs-storage:1024,cache=writeback     # NFS storage
qm set 100 --scsi0 local:1024,cache=writeback           # Local storage

# Multiple disks
qm set 100 --scsi0 local-lvm:100                        # First disk (100GB)
qm set 100 --scsi1 local-lvm:500                        # Second disk (500GB)
```

Try the corrected command:
```bash
qm set 100 --scsi0 local-lvm:1024,cache=writeback,discard=on
```

This should work! Let me know if you encounter any other issues.

---

### 👤 You

root@bojie2:/var/lib/vz/template/iso# qm set 100 --scsi0 local-lvm:1024,cache=writeback,discard=on
update VM 100: -scsi0 local-lvm:1024,cache=writeback,discard=on
  WARNING: You have not turned on protection against thin pools running out of space.
  WARNING: Set activation/thin_pool_autoextend_threshold below 100 to trigger automatic extension of thin pools before they get full.
  Logical volume "vm-100-disk-0" created.
  WARNING: Sum of all thin volume sizes (1.00 TiB) exceeds the size of thin pool pve/data and the amount of free space in volume group (40.30 GiB).
  Logical volume pve/vm-100-disk-0 changed.
scsi0: successfully created disk 'local-lvm:vm-100-disk-0,cache=writeback,discard=on,size=1T'

I have just mounted a 10TB before, but it still shows 1TB

---

### 👤 You

root@bojie2:/var/lib/vz/template/iso# qm set 100 --scsi0 local-lvm:1024,cache=writeback,discard=on
update VM 100: -scsi0 local-lvm:1024,cache=writeback,discard=on
  WARNING: You have not turned on protection against thin pools running out of space.
  WARNING: Set activation/thin_pool_autoextend_threshold below 100 to trigger automatic extension of thin pools before they get full.
  Logical volume "vm-100-disk-0" created.
  WARNING: Sum of all thin volume sizes (1.00 TiB) exceeds the size of thin pool pve/data and the amount of free space in volume group (40.30 GiB).
  Logical volume pve/vm-100-disk-0 changed.
scsi0: successfully created disk 'local-lvm:vm-100-disk-0,cache=writeback,discard=on,size=1T'

I have just mounted a 10TB NFS, but why it cannot be used for local-lvm

---

### 🤖 Cursor Assistant

The issue is that **`local-lvm`** and your **NFS storage** are completely different storage backends in Proxmox! You need to specify the correct storage name.

## The Problem

- `local-lvm` is a **local LVM thin pool** on your PVE host's local disks (only has 40GB free)
- Your **10TB NFS** is a separate storage that has a different name
- The warning shows you've overcommitted the thin pool dangerously (1TB allocated, only 40GB actually available)

## Check Available Storage

```bash
# List all storage
pvesm status

# You should see something like:
# Name          Type     Status    Total        Used      Available    %
# local         dir      active    50GB         30GB      20GB         60%
# local-lvm     lvmthin  active    45GB         5GB       40GB         11%
# nfs-storage   nfs      active    10TB         840GB     8.6TB        9%
```

The NFS storage will have its own name (like `nfs-storage` or whatever you named it).

## Find Your NFS Storage Name

```bash
# Check storage configuration
cat /etc/pve/storage.cfg

# Look for an entry like:
# nfs: nfs-storage
#         export /export/pve-storage
#         path /mnt/pve/nfs-storage
#         server bsql-storage.01.me
#         content images,rootdir,vztmpl,iso,backup
```

The name after `nfs:` is what you need to use.

## Solution: Delete and Recreate on NFS

```bash
# 1. Delete the incorrectly created disk
qm set 100 --delete scsi0

# 2. Recreate on NFS (replace 'nfs-storage' with your actual NFS storage name)
qm set 100 --scsi0 nfs-storage:1024,cache=writeback

# 3. Verify
qm config 100
pvesm status
```

## If You Don't Have NFS Storage Configured Yet

If the NFS isn't showing in `pvesm status`, you need to add it first:

```bash
# Add NFS storage to PVE (if not already done)
pvesm add nfs nfs-storage \
  --server bsql-storage.01.me \
  --export /export/pve-storage \
  --content images,rootdir,vztmpl,iso,backup

# Verify it's available
pvesm status

# Now create disk on NFS
qm set 100 --scsi0 nfs-storage:1024,cache=writeback
```

## Complete Example

```bash
# Full workflow:

# 1. Check what storage you have
pvesm status

# 2. If NFS not listed, add it
pvesm add nfs nfs-storage \
  --server bsql-storage.01.me \
  --export /export/pve-storage \
  --content images,rootdir

# 3. Remove the wrongly created disk on local-lvm
qm set 100 --delete scsi0

# 4. Create disk on NFS storage
qm set 100 --scsi0 nfs-storage:1024,cache=writeback

# 5. Verify
qm config 100 | grep scsi0
# Should show: scsi0: nfs-storage:vm-100-disk-0,cache=writeback,size=1T
```

## Understanding Storage Types

| Storage Name | Type | Location | Your Case |
|--------------|------|----------|-----------|
| `local` | Directory | Local disk | Small, for ISOs/templates |
| `local-lvm` | LVM-thin | Local disk | Only 40GB free ⚠️ |
| `nfs-storage` | NFS | Remote 10TB | **Use this!** ✅ |

## Warning About Thin Pool Overcommit

The warning you got is serious:

```
WARNING: Sum of all thin volume sizes (1.00 TiB) exceeds the size of thin pool 
pve/data and the amount of free space in volume group (40.30 GiB).
```

This means:
- You allocated 1TB
- But only 40GB is actually available
- If the VM uses more than 40GB, **the host will crash**
- This is **dangerous** for production

**Fix it immediately:**
```bash
# Delete the thin-provisioned disk
qm set 100 --delete scsi0

# Use NFS instead
qm set 100 --scsi0 nfs-storage:1024,cache=writeback
```

## Verify NFS Disk Was Created

```bash
# Check VM config
qm config 100

# Should show:
# scsi0: nfs-storage:vm-100-disk-0,cache=writeback,size=1T

# Verify on NFS host
# On bsql-storage.01.me:
ls -lh /export/pve-storage/
# Should see: images/100/vm-100-disk-0.raw or similar
```

## If You're in a Cluster

If you set up the cluster earlier, adding storage once will make it available on all nodes:

```bash
# Run on any node
pvesm add nfs nfs-storage \
  --server bsql-storage.01.me \
  --export /export/pve-storage \
  --content images,rootdir,vztmpl,iso,backup

# It will automatically sync to all cluster nodes
# Verify on other nodes:
pvesm status
```

**Summary**: Replace `local-lvm` with your NFS storage name (likely `nfs-storage`) to use your 10TB NFS mount. The `local-lvm` is a completely separate storage backend on local disks with very limited space.

What's the output of `pvesm status`? That will show your NFS storage name.

---

### 👤 You

Why after boot, the console shows nothing, and the reboot failed

---

### 👤 You

Why after boot, the console shows nothing, and the reboot failed

---

### 👤 You

Why after boot, the console shows nothing, and the reboot failed

---

### 👤 You

Why after boot, the console shows nothing, and the reboot failed

---

### 👤 You

parted command not found, how to install in livecd

---

### 🤖 Cursor Assistant

In a Debian/Ubuntu live CD environment, you can install `parted` using `apt`:

```bash
# Update package list
apt update

# Install parted
apt install parted -y

# Verify it's installed
parted --version
```

## Alternative: Use `fdisk` (Usually Pre-installed)

If you want to avoid installing packages, `fdisk` is usually already available and can do the same job:

```bash
# For BIOS boot (MBR partition table)
fdisk /dev/sda

# Commands to use in fdisk:
# n = new partition
# p = primary partition
# 1 = partition number
# (press Enter twice for default start/end)
# w = write changes and exit

# Quick script:
(echo o; echo n; echo p; echo 1; echo ""; echo ""; echo w) | fdisk /dev/sda

# Format the partition
mkfs.ext4 /dev/sda1
```

## For UEFI Boot with `fdisk`

```bash
fdisk /dev/sda

# In fdisk:
# g = create GPT partition table
# n = new partition (EFI, 512MB)
# (partition 1, default start, +512M for size)
# t = change type
# 1 = EFI System
# n = new partition (root, rest of disk)
# (partition 2, default start and end)
# w = write

# Or as a script:
(echo g; echo n; echo 1; echo ""; echo +512M; echo t; echo 1; echo n; echo 2; echo ""; echo ""; echo w) | fdisk /dev/sda

# Format EFI partition
mkfs.fat -F32 /dev/sda1

# Format root partition
mkfs.ext4 /dev/sda2
```

## Quick Install Multiple Useful Tools

While you're at it, install other useful tools for the migration:

```bash
apt update
apt install -y parted rsync openssh-server vim nano curl wget net-tools
```

## If `apt` Doesn't Work (Minimal Live CD)

Some minimal live CDs might not have networking configured:

```bash
# Configure network first
dhclient

# Or manually:
ip link set <interface> up
dhclient <interface>

# Test connectivity
ping -c 3 8.8.8.8

# Then run apt install
apt update
apt install parted -y
```

## Using Parted - Quick Reference

Once installed:

```bash
# BIOS/MBR partitioning
parted /dev/sda --script -- \
  mklabel msdos \
  mkpart primary ext4 1MiB 100%

mkfs.ext4 /dev/sda1

# UEFI/GPT partitioning
parted /dev/sda --script -- \
  mklabel gpt \
  mkpart ESP fat32 1MiB 512MiB \
  set 1 esp on \
  mkpart primary ext4 512MiB 100%

mkfs.fat -F32 /dev/sda1
mkfs.ext4 /dev/sda2
```

The simple answer: **`apt install parted -y`** after running `apt update` in the live environment!

---

### 👤 You

There is no openssh-server in debian

---

### 🤖 Cursor Assistant

You're right - some minimal Debian live images don't include `openssh-server` in their repositories. Here are solutions:

## Solution 1: Check if SSH Server is Already Running

```bash
# Check if SSH daemon is already running
systemctl status sshd
# or
systemctl status ssh

# If it exists but stopped, start it
systemctl start ssh
```

## Solution 2: Try Different Package Names

```bash
# Try these variations
apt update
apt install ssh -y
# or
apt install openssh-server -y
# or
apt install dropbear -y  # Lightweight SSH server
```

## Solution 3: Reverse the Rsync Direction (Recommended)

Instead of pulling from source to target, **push from source to target**. This way you don't need SSH server on the target:

```bash
# On TARGET VM (in live CD)
# Just get the IP address
ip addr show
# Note the IP, e.g., 192.168.1.100

# Make sure target filesystem is mounted
mount /dev/sda1 /mnt/target  # or sda2 for UEFI

# On SOURCE VM (your existing VM to migrate)
# Push to target (no SSH server needed on target)
rsync -aAXHv --progress -e ssh \
  --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found","/swapfile"} \
  / root@TARGET_IP:/mnt/target/
```

Wait, that still needs SSH on target. Let me provide better solution:

## Solution 4: Use Alternative Transfer Method - netcat

On **TARGET** (live CD):
```bash
# Install netcat if needed
apt install netcat-traditional -y
# or
apt install ncat -y

# Receive on target (port 9999)
cd /mnt/target
nc -l -p 9999 | tar xzf -
```

On **SOURCE**:
```bash
# Send from source
tar czf - \
  --exclude='/dev/*' \
  --exclude='/proc/*' \
  --exclude='/sys/*' \
  --exclude='/tmp/*' \
  --exclude='/run/*' \
  --exclude='/mnt/*' \
  --exclude='/media/*' \
  --exclude='/lost+found' \
  --exclude='/swapfile' \
  / | nc TARGET_IP 9999
```

## Solution 5: Use NFS Mount (Easiest!)

Since you already have NFS storage, use that as intermediary:

On **SOURCE VM**:
```bash
# Mount NFS
mkdir -p /mnt/nfs-backup
mount -t nfs bsql-storage.01.me:/export/pve-storage /mnt/nfs-backup

# Create backup directory
mkdir -p /mnt/nfs-backup/vm-migration

# Rsync to NFS
rsync -aAXHv --progress \
  --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found","/swapfile"} \
  / /mnt/nfs-backup/vm-migration/
```

On **TARGET VM** (in live CD):
```bash
# Install NFS client
apt update
apt install nfs-common -y

# Mount same NFS
mkdir -p /mnt/nfs-source
mount -t nfs bsql-storage.01.me:/export/pve-storage /mnt/nfs-source

# Mount target disk
mount /dev/sda1 /mnt/target

# Copy from NFS to target
rsync -aAXHv --progress /mnt/nfs-source/vm-migration/ /mnt/target/

# Cleanup when done
umount /mnt/nfs-source
# On source, delete: rm -rf /mnt/nfs-backup/vm-migration
```

## Solution 6: Enable SSH via PVE Host Forwarding

Forward a port from PVE host to the VM:

```bash
# On PVE host, find VM's IP
qm guest exec 100 -- ip addr show

# Setup SSH port forwarding (if VM has SSH)
# Or setup a reverse tunnel...
```

Actually, this is getting complex.

## **Recommended Approach: NFS Method (Solution 5)**

This is the cleanest since you already have NFS set up:

**Step-by-step:**

1. **On SOURCE VM:**
```bash
mkdir /mnt/backup
mount -t nfs bsql-storage.01.me:/export/pve-storage /mnt/backup
mkdir /mnt/backup/migration-temp
rsync -aAXHv --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found","/swapfile"} / /mnt/backup/migration-temp/
umount /mnt/backup
```

2. **On TARGET VM (live CD):**
```bash
apt update && apt install nfs-common -y
mount /dev/sda1 /mnt/target  # your target partition
mkdir /mnt/nfs
mount -t nfs bsql-storage.01.me:/export/pve-storage /mnt/nfs
rsync -aAXHv /mnt/nfs/migration-temp/ /mnt/target/
umount /mnt/nfs
```

3. **Cleanup (on NFS host or any machine):**
```bash
ssh bsql-storage.01.me
rm -rf /export/pve-storage/migration-temp
```

This avoids needing SSH server in the live CD entirely! The NFS acts as an intermediary storage.

**Which approach would you like to use?** I recommend the NFS method since you already have that infrastructure set up.

---

### 👤 You

root@bojpve:~# qm set 102 --scsi0 nfs-storage:1024,format=qcow2,iothread=on,cache=writeback
update VM 102: -scsi0 nfs-storage:1024,format=qcow2,iothread=on,cache=writeback
Formatting '/mnt/pve/nfs-storage/images/102/vm-102-disk-0.qcow2', fmt=qcow2 cluster_size=65536 extended_l2=off preallocation=metadata compression_type=zlib size=1099511627776 lazy_refcounts=off refcount_bits=16




^C
root@bojpve:~# qm set 102 --scsi0 nfs-storage:1024,iothread=1,cache=writeback
update VM 102: -scsi0 nfs-storage:1024,iothread=1,cache=writeback
trying to acquire cfs lock 'storage-nfs-storage' ...
trying to acquire cfs lock 'storage-nfs-storage' ...
trying to acquire cfs lock 'storage-nfs-storage' ...
trying to acquire cfs lock 'storage-nfs-storage' ...
trying to acquire cfs lock 'storage-nfs-storage' ...
trying to acquire cfs lock 'storage-nfs-storage' ...
trying to acquire cfs lock 'storage-nfs-storage' ...
trying to acquire cfs lock 'storage-nfs-storage' ...
^C

--
How to kill the running process

---

### 🤖 Cursor Assistant

The process is stuck, likely because the first `qm set` command is still running in the background (formatting the 1TB qcow2 took a lock). Here's how to fix it:

## Step 1: Kill the Stuck Processes

```bash
# Find the stuck qm/qemu processes
ps aux | grep -E "qm set|qemu-img"

# Kill them (replace PID with actual process IDs)
pkill -9 qm
pkill -9 qemu-img

# Or more targeted:
ps aux | grep "qm set 102" | grep -v grep | awk '{print $2}' | xargs kill -9
ps aux | grep "qemu-img" | grep -v grep | awk '{print $2}' | xargs kill -9
```

## Step 2: Clear the Storage Lock

```bash
# Remove the cluster filesystem lock
rm -f /var/lock/qemu-server/lock-102.conf

# Clear pmxcfs locks (Proxmox cluster filesystem)
# Check what locks exist
ls -la /etc/pve/.locks/

# Remove storage lock
rm -f /etc/pve/.locks/storage-nfs-storage

# Restart cluster filesystem if needed
systemctl restart pve-cluster
systemctl restart pvedaemon
```

## Step 3: Clean Up Partial Disk Image

```bash
# Check if partial disk was created
ls -lh /mnt/pve/nfs-storage/images/102/

# Remove partial/incomplete disk
rm -f /mnt/pve/nfs-storage/images/102/vm-102-disk-0.qcow2
rm -rf /mnt/pve/nfs-storage/images/102/
```

## Step 4: Verify and Reset VM Config

```bash
# Check VM config
qm config 102

# If scsi0 shows up, delete it
qm set 102 --delete scsi0

# Verify it's gone
qm config 102
```

## Step 5: Recreate Disk with Better Settings

The issue is that **qcow2 format on NFS is very slow** for large disks. Use **raw format** instead:

```bash
# Use raw format (much faster, better for NFS)
qm set 102 --scsi0 nfs-storage:1024,cache=writeback

# This will create a raw disk instantly (sparse file, no pre-allocation)
```

If you really need qcow2, use `preallocation=off`:

```bash
# Faster qcow2 creation (but still slower than raw)
qm set 102 --scsi0 nfs-storage:1024,format=qcow2,cache=writeback
```

## Complete Recovery Script

```bash
#!/bin/bash

echo "Killing stuck processes..."
pkill -9 qm
pkill -9 qemu-img
sleep 2

echo "Removing locks..."
rm -f /var/lock/qemu-server/lock-102.conf
rm -f /etc/pve/.locks/storage-nfs-storage
rm -f /etc/pve/.locks/*

echo "Restarting services..."
systemctl restart pve-cluster
systemctl restart pvedaemon
sleep 5

echo "Cleaning up partial disk..."
rm -rf /mnt/pve/nfs-storage/images/102/

echo "Removing disk from VM config..."
qm set 102 --delete scsi0 2>/dev/null || true

echo "Ready to recreate disk!"
echo "Run: qm set 102 --scsi0 nfs-storage:1024,cache=writeback"
```

## Understanding the Problem

1. **First command** with `format=qcow2,preallocation=metadata`:
   - Tried to pre-allocate metadata for 1TB qcow2 file
   - Very slow on NFS (can take 10-30 minutes)
   - Still running in background when you Ctrl+C'd

2. **Second command**:
   - Couldn't acquire lock because first command still held it
   - Got stuck waiting

## Best Practices for NFS Storage

```bash
# For NFS, prefer RAW format (best performance)
qm set 102 --scsi0 nfs-storage:1024,cache=writeback

# If you need qcow2 features (snapshots), use:
qm set 102 --scsi0 nfs-storage:1024,format=qcow2,cache=writeback
# (without preallocation or iothread)

# Note: iothread works best with raw format on local SSDs
# For NFS, iothread usually doesn't help much
```

## Verify Everything is Clean

After cleanup:

```bash
# Check no stuck processes
ps aux | grep -E "qm|qemu-img" | grep 102

# Check no locks
ls -la /etc/pve/.locks/

# Check storage
ls -la /mnt/pve/nfs-storage/images/

# Check VM config
qm config 102

# Check cluster status
pvecm status
```

## Quick Fix Now

Run these commands:

```bash
pkill -9 qm qemu-img
rm -f /etc/pve/.locks/storage-nfs-storage
systemctl restart pve-cluster pvedaemon
sleep 5
rm -rf /mnt/pve/nfs-storage/images/102/
qm set 102 --delete scsi0
qm set 102 --scsi0 nfs-storage:1024,cache=writeback
```

This should get you unstuck and create the disk quickly!

---


*Exported from [Cursor View](https://github.com/saharmor/cursor-view)*