For my new homelab cluster I’ve built up a fresh Ceph filesystem to store certain chunks of my data and found the need to mount both to one of my nodes. Normally I use ceph-fuse through /etc/fstab, so I simply modified with the following.
root@storage:~# grep fuse /etc/fstab none /mnt/storage/ceph fuse.ceph ceph.id=admin,ceph.conf=/etc/ceph/ceph.conf,_netdev,defaults 0 0 none /mnt/storage/ceph-old fuse.ceph ceph.id=admin,ceph.conf=/etc/ceph-old/ceph.conf,_netdev,defaults 0 0
The /etc/ceph-old/ is a copy of my config files from the older cluster. In the /etc/ceph-old/ceph.conf file I added the following, since the keyring for the that cluster is not in the default path.
[client.admin] keyring = /etc/ceph-old/ceph.client.admin.keyring
Anytime the ceph.conf from the old cluster is used so is the old keyring and the cluster mounts up just fine.
Filesystem Type Size Used Avail Use% Mounted on ceph-fuse fuse.ceph-fuse 100T 91T 9.4T 91% /mnt/storage/ceph-old