LVM Volume Lifecycle Management

🖧 Infrastructure Context

Access via SSH from the default terminal. The cluster topology is defined below:

📄 /etc/hosts (Cluster Inventory)


# Management & Controller
10.0.0.15   terminal       # Main Entry Point

# Web & Application Tier
10.0.0.60   web-srv1   # Nginx / Apache
10.0.0.70   app-srv1    # Backend App

# Data Persistence Tier
10.0.0.80   data-001    # Primary DB
10.0.0.90   data-002    # Replica / Backup

# Virtualization & Containers
10.0.0.100  kvm-001        # Libvirt Hypervisor
10.0.0.110  docker-001     # Container Runtime

⚠️

Constraint: Nested SSH is forbidden. Connect directly from terminal to target IPs.

📋 Engineering Requirements

Business Context: A storage optimization initiative requires decommissioning the physical disk /dev/vdh from the existing volume group vol1. This disk must be repurposed to create a new isolated storage group (vol2) for a specific project.

Technical Objectives:

Hot Migration: Evacuate data from /dev/vdh without service interruption using LVM mirroring capabilities.
Topology Change: Remove /dev/vdh from vol1 and initialize a new Volume Group vol2.
Provisioning: Create a Logical Volume p1 (50 MiB) within vol2.
Filesystem: Format the new volume with ext4.

🔧 Implementation Procedure

Analyze Storage Topology

Confirm the current layout and verify /dev/vdh is part of vol1.
Ventana de terminal
```
sudo pvs
sudo vgs
```
Data Evacuation (pvmove)

Relocate allocated physical extents (PE) from the target disk to other free disks within the same Volume Group.
Ventana de terminal
```
# Verify allocation
sudo pvdisplay -m /dev/vdh

# Migrate data
sudo pvmove /dev/vdh
```
Decommission Disk

Once the disk is fully free, remove it from the Volume Group.
Ventana de terminal
```
sudo vgreduce vol1 /dev/vdh
```
Initialize New Storage Group

Create the new Volume Group vol2 using the reclaimed physical volume.
Ventana de terminal
```
sudo vgcreate vol2 /dev/vdh
```
Provision Logical Volume

Allocate the requested storage capacity.
Ventana de terminal
```
sudo lvcreate -n p1 -L 50M vol2
```
Apply Filesystem

Format the block device.
Ventana de terminal
```
sudo mkfs.ext4 /dev/vol2/p1
```
Final Validation

Verify the new LVM structure and filesystem signature.
Ventana de terminal
```
sudo lvs -o lv_name,vg_name,lv_size,seg_pe_ranges
lsblk -f /dev/vol2/p1
```

🔍 Troubleshooting

“Physical volume is still in use”: The vgreduce command will fail if you skipped Step 2. You must evacuate data first.
“Insufficient free extents”: If vol1 does not have enough free space on other disks (e.g., /dev/vdb) to hold the data from /dev/vdh, the pvmove operation will fail.