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