Make backup of other pc? (promox)

im running Kopia inside a LXC proxmox.
it work fine… but…i want to make backup of some directories inside other LXC of proxmox.
How i could do that?
It is possible or with Kopia i just can make backup of local directorys?
if just local… i can make the directories of others LXC local in the Kopia container?

Local only - yes. Which means that you can mount other server directories and run kopia on them. SMB/NFS - whatever suits you best is an answer.