I recently upgraded my Homelab Proxmox host server and wanted to repurpose my existing server to use as a testing environment. Below are the steps I used to rename the old Proxmox instance. These steps worked for me. Please let me know in the comments if you try these steps and if any issues arise that I didn't have in my environment.
NOTE: Renaming a node that is part of a cluster is not recommended. These steps are intended for standalone nodes. Always make backups of important VMs before attempting to modify the Proxmox host.
1. Log into ProxMox VE, either at the console, via SSH or the web UI, and launch the web shell
2. Run the following commands, alternatively, you can manually edit each file mentioned with nano or vi and replace the old hostname with the new one
# set the old hostname and write to ini
echo "OLD_HOSTNAME=$(hostname)" > ~/pmrename.ini# set the new hostname in ini, update as needed
echo "NEW_HOSTNAME=vm-dev" >> ~/pmrename.ini# edit hostname variables in ini file
nano pmrename.ini# read variables from ini
source <(grep = ~/pmrename.ini)# edit hostname file
sed -i.bak "s/$OLD_HOSTNAME/$NEW_HOSTNAME/gi" /etc/hostname# edit hosts file
sed -i.bak "s/$OLD_HOSTNAME/$NEW_HOSTNAME/gi" /etc/hosts# edit mailname if it exists
[ -e "/etc/mailname" ] && sed -i.bak "s/$OLD_HOSTNAME/$NEW_HOSTNAME/gi" /etc/mailname# edit main.cf if it exists
[ -e "/etc/postfix/main.cf" ] && sed -i.bak "s/$OLD_HOSTNAME/$NEW_HOSTNAME/gi" /etc/postfix/main.cf# copy config files to new node name
cp "/var/lib/rrdcached/db/pve2-node/$OLD_HOSTNAME" "/var/lib/rrdcached/db/pve2-node/$NEW_HOSTNAME" -rcp "/var/lib/rrdcached/db/pve2-storage/$OLD_HOSTNAME" "/var/lib/rrdcached/db/pve2-storage/$NEW_HOSTNAME" -r cp "/var/lib/rrdcached/db/pve2-$OLD_HOSTNAME" "/var/lib/rrdcached/db/pve2-$NEW_HOSTNAME" -r# reboot
reboot now3. Wait for the Proxmox host to come back up
4. Log back in and continue with the following commands
# read variables from ini
source <(grep = ~/pmrename.ini)# update storage config
sed -i.bak "s/nodes $OLD_HOSTNAME/nodes $NEW_HOSTNAME/gi" /etc/pve/storage.cfg# mv vm configs
mv /etc/pve/nodes/$OLD_HOSTNAME/qemu-server/*.conf /etc/pve/nodes/$NEW_HOSTNAME/qemu-server/# mv ct configs
mv /etc/pve/nodes/$OLD_HOSTNAME/lxc/*.conf /etc/pve/nodes/$NEW_HOSTNAME/lxc/5. Test that Proxmox web UI and all VMs are working as intended
1. After fully testing everything is working, run the following commands to clean up backup files
# read variables from ini
source <(grep = ~/pmrename.ini) rm /etc/hostname.bak && rm /etc/hosts.bak [ -e "/etc/mailname.bak" ] && rm /etc/mailname.bak[ -e "/etc/postfix/main.cf.bak" ] && rm /etc/postfix/main.cf.bak rm /var/lib/rrdcached/db/pve2-node/$OLD_HOSTNAME -rrm /var/lib/rrdcached/db/pve2-storage/$OLD_HOSTNAME -r rm /var/lib/rrdcached/db/pve2-$OLD_HOSTNAME -r rm /etc/pve/nodes/$OLD_HOSTNAME -r rm /etc/pve/storage.cfg.bak rm ~/pmrename.iniSource: https://pve.proxmox.com/wiki/Renaming_a_PVE_node and https://i12bretro.github.io/tutorials/0633.html