Peng Yu writes:

(...) http://serverfault.com/questions/19323/is-it-feasible-to-have-home-folder-ho...

I see on the above URL that OpenLDAP can be used to sync UID/GID. But it is not clear to how to do it. Could anybody point me some directions? Thanks.

"... as you have to keep the UID and GIDs in sync - use something like OpenLDAP ..."

Read those words in context - they're from a reply to the previous paragraph in that URL:

If you NFS-mount file systems but keep users' UIDs/GIDs of in local files (/etc/passwd & co), *then* you need to keep these files in sync between the hosts. So instead keep the UIDs/GIDs in a single place - OpenLDAP - and set up your machines to get the users' UIDs/GIDs from there.

You can sync to a backup LDAP server with syncrepl/syncprov, but that's another matter.

Anyway, configure pam and nss to get user/group info from LDAP. You'll likely want to cache LDAP results locally, but avoid the problematic "nscd" program for that. sssd-ldap or OpenLDAP:slapo-nssov seem to be the stuff to look at nowadays, but I have not kept track. There's plenty to read about it on www.