Proxmox - Cluster IPs ändern

# 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/10\.10\.20\./10.10.0./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/10\.10\.20\./10.10.0./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
# (thanks u/FortunatelyLethal)
# :%s/10\.10\.20\./10.10.0./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 '10\.10\.0\.' *
cd /var
grep -R '10\.10\.0\.' *

# Reboot the system to cleanly restart all the networking and services
reboot

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