Márcio Fernandes
7ce3365ea2
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154 lines
3.5 KiB
Markdown
154 lines
3.5 KiB
Markdown
# Proxmox Node Restore
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Restores a Proxmox node exactly as it previously existed, allowing it to rejoin the cluster without using `pvecm delnode`.
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It works by reconstructing the node’s identity vectors so Corosync and pmxcfs accept it as the same entity.
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This method is **not guaranteed** and depends on perfect identity matching.
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If any identity vector differs (hostname, node ID, ring IP, certificates), the node may:
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- fail to mount pmxcfs
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- fail to join Corosync
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- appear as a ghost node
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- destabilize the cluster
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Use this approach only when you fully understand the identity requirements and the cluster
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is otherwise healthy.
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- [1. Hostname Identity](#1-hostname-identity)
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- [2. Local Name Resolution](#2-local-name-resolution)
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- [3. System Users and Groups](#3-system-users-and-groups)
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- [4. Network Topology](#4-network-topology)
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- [5. VFIO Bindings (If Using Passthrough)](#5-vfio-bindings-if-using-passthrough)
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- [6. Kernel Flags and Module Loading (If Restoring GRUB)](#6-kernel-flags-and-module-loading-if-restoring-grub)
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- [7. Disk Configuration](#7-disk-configuration)
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- [8. SSH Identity](#8-ssh-identity)
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- [9. Corosync Identity](#9-corosync-identity)
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- [single node custer](#single-node-custer)
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- [Multi node cluster](#multi-node-cluster)
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- [10. Node‑Specific Artifacts](#10-nodespecific-artifacts)
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- [11. Finalize](#11-finalize)
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## 1. Hostname Identity
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Preserve the node’s cluster identity.
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- Restore `/etc/hostname`
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---
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## 2. Local Name Resolution
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Ensure the node can resolve itself and its peers.
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- Restore `/etc/hosts`
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## 3. System Users and Groups
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Restore OS‑level identity and UID/GID mapping.
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- Restore `/etc/passwd`
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- Restore `/etc/group`
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---
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## 4. Network Topology
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Restore bridges, VLANs, MTU, and IP assignments.
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- Restore `/etc/network/interfaces`
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- Restore `/etc/network/interfaces.d/`
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---
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## 5. VFIO Bindings (If Using Passthrough)
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Restore PCI passthrough behavior.
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- Restore `/etc/modprobe.d/`
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---
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## 6. Kernel Flags and Module Loading (If Restoring GRUB)
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Restore passthrough‑related kernel parameters.
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- Restore `/etc/default/grub`
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- Restore `/etc/modules`
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- Restore `/etc/modules.d/`
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---
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## 7. Disk Configuration
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Restore storage layout and ZFS pools.
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- Restore `/etc/fstab`
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- Import ZFS pools (example: `zfs import fastcore`)
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---
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## 8. SSH Identity
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Restore admin access and host identity.
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- Restore `/root/.ssh/*`
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- Restore `/etc/ssh/*`
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---
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## 9. Corosync Identity
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### single node custer
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In some cases, a single Proxmox node can be resurrected simply by restoring the entire
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`/etc/pve` directory from backup. This works because `/etc/pve` (pmxcfs) contains:
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- Corosync identity (node ID, ring IPs, cluster membership)
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- Cluster certificates
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- Node‑specific configuration
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- Storage definitions
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- VM/CT configuration metadata
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If the restored node has **the same hostname, same IPs, same Corosync ring addresses, and
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the cluster still contains the old node entry**, then copying the full `/etc/pve` state
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can allow the node to rejoin the cluster as if nothing happened.
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### Multi node cluster
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Reconstruct the node’s cluster identity (Rejoin Without Delnode).
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- Restore `/etc/pve/corosync.conf`
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- Restore `/etc/pve/corosync.pub`
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- Restore `/etc/corosync/authkey`
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These define:
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- cluster topology
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- node ID
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- ring IPs
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- shared authentication
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---
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## 10. Node‑Specific Artifacts
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Restore semantic overlays and local scripts.
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- Restore `/home/`
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- Restore `/root/`
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- Restore `/opt/`
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---
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## 11. Finalize
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If GRUB was restored:
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- Run `update-grub`
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Then:
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- Reboot
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---
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