Thanks @DvdNwk for the very helpful information!
This is what it took for me on a single node PVE 8.4.14 non-subscription, minus bunny trails:
1. Back up the entire pve config:
2. Set the new hostname:
3. Update the hostname in
4. Update the Postfix config in
5. Disable starting guests on reboot:
6. Reboot:
7. Stop the cluster filesystem:
8. Run
9. Go into the nodes config dir:
10. Delete the NEW dir that was created after the hostname changed:
11. Copy the node folder over:
12. Copy over the VMs configuration using different IDs:
13, Do similar for any containers in
14. Remove the old files:
15. Rename the files back to the original IDs:
16. Do similar for any containers in
17. Go into the rrdcached folder:
18. Copy the old folder into the new:
19. Remove the old folder:
20. Do the same in
21. Re-enable starting guests on reboot:
22. Reboot:
23. Once you are confident everything is working, you can remove the backup:
This is what it took for me on a single node PVE 8.4.14 non-subscription, minus bunny trails:
1. Back up the entire pve config:
cp -r /etc/pve /root/pve_backup2. Set the new hostname:
hostnamectl hostname NEW3. Update the hostname in
/etc/hosts – replace OLD with NEW, might be a good idea to leave an entry with the old hostname though.4. Update the Postfix config in
/etc/postfix/main.cf – replace OLD with NEW5. Disable starting guests on reboot:
systemctl disable pve-guests6. Reboot:
reboot7. Stop the cluster filesystem:
systemctl stop pve-cluster (DON'T do it if you're connected via the web gui - you will probably lose access and be forced to gain shell access some other way.) Not 100% sure if it is necessary but I did it.8. Run
pmxcfs -l - should succeed without lock errors9. Go into the nodes config dir:
cd /etc/pve/nodes10. Delete the NEW dir that was created after the hostname changed:
rm -rf NEW11. Copy the node folder over:
cp -r OLD NEW This will print a bunch of cp: cannot create regular file 'NEW/qemu-server/XXXX.conf': File exists Don't worry, the rest of the files should have been copied with no problems. This is because /etc/pve is actually a virtual file system that doesn't like to have duplicate VM/container configuration files.12. Copy over the VMs configuration using different IDs:
for file in OLD/qemu-server/*.conf; do cp "$file" "NEW/qemu-server/9$(basename $file)"; done This command will prefix everything with an extra 9, so make sure none of your VMs have an ID starting with 9 to avoid issues later.13, Do similar for any containers in
OLD/lxc.14. Remove the old files:
rm -rf OLD15. Rename the files back to the original IDs:
for file in NEW/qemu-server/9*.conf; do mv $file NEW/qemu-server/${file##*/9}; done16. Do similar for any containers in
NEW/lxc.17. Go into the rrdcached folder:
cd /var/lib/rrdcached/db/pve2-node/18. Copy the old folder into the new:
cp -r OLD NEW19. Remove the old folder:
rm -rf OLD20. Do the same in
/var/lib/rrdcached/db/pve2-storage21. Re-enable starting guests on reboot:
systemctl enable pve-guests22. Reboot:
reboot23. Once you are confident everything is working, you can remove the backup:
rm -rf /root/pve_backup
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