Change the IP Address of a Proxmox Clustered Node

First stop the cluster services

systemctl stop pve-cluster
systemctl stop corosync

Mount the filesystem locally

pmxcfs -l

Edit the network interfaces file to have the new IP information

Be sure to replace both the address and gateway

nano /etc/network/interfaces

Replace any host entries with the new IP addresses

nano /etc/hosts

Change the DNS server as necessary

nano /etc/resolv.conf

Edit the corosync file and replace the old IPs with the new IPs for all hosts

:%s/192\.168\.1\./192.168.2./g <- vi command to replace all instances

BE SURE TO INCREMENT THE config_version: x LINE BY ONE TO ENSURE THE CONFIG IS NOT OVERWRITTEN

nano /etc/pve/corosync.conf

Edit the known hosts file to have the correct IPs

:%s/192\.168\.1\./192.168.2./g <- vi command to replace all instances

nano/etc/pve/priv/known_hosts

If using ceph, edit the ceph configuration file to reflect the new network

:%s/192\.168\.1\./192.168.2./g <- vi command to replace all instances

nano /etc/ceph/ceph.conf

If you want to be granular... fix the IP in /etc/issue

nano /etc/issue

Verify there aren't any stragglers with the old IP hanging around

cd /etc
grep -R '192\.168\.1\.' *
cd /var
grep -R '192\.168\.1\.' *

Reboot the system to cleanly restart all the networking and services

reboot now

Bibliography

https://forum.proxmox.com/threads/change-cluster-nodes-ip-addresses.33406/ https://pve.proxmox.com/wiki/Cluster_Manager#_remove_a_cluster_node

Last modified: 14 January 2025