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Alexander
Asked: 2013-06-08 05:47:26 +0800 CST

Mapping UID and GID of local user to the mounted NFS share

  • 772

I have a server with NFSv4. I am mounting contents of the home folder of remote user to local host. Able to read and write contents, but when I am checking ownership of files at the mounted volume from the local host, they all belongs to corresponding remote user and group (512). Is there any way to make it look like they belong to the local user and group (1000) on the local host?

/etc/exports on remote host (IP is 192.168.1.110)

/home/user512 192.168.1.142(rw,sync,all_squash,anonuid=512,anongid=512)

/etc/fstab on local host (IP is 192.168.1.142)

192.168.1.110:/home/user512    /home/localuser/projects/project512   nfs    rw,hard,intr,rsize=32768,wsize=32768    0       0
nfs

4 Answers

  1. Best Answer

    This is what idmapping is suppose to do. First of all, enable is on the client and server:

    # echo N > /sys/module/nfs/parameters/nfs4_disable_idmapping

    clean idmap cache and restart idmap daemon:

    # nfsidmap -c
# service rpcidmapd restart

    Now on server and the client will send instead of numeric IDs string principals like [email protected]. You need to have bob account on the both hosts - client and server. Nevertheless, the numeric ID's can be different.

    • 53

  2. You have all the pieces there. From the exportfs man page, all_squash maps all uids and gids to the anonymous versions. What you wrote forced those values to be 512. If you changed to 1000, the nfs server on the remote host would make everything 1000, and access should be granted.

    • 9

  3. on your nfs client, edit /etc/idmapd.conf and change 

    [Mapping]

Nobody-User = myappuser
Nobody-Group = myappuser

    afther this restart the nfs service

    • 4

  4. I was able to fix nobody:nobody ownership issue over NFS on CentOS 6 (server) + 7 (client) with two changes:

    1. Make sure the /etc/idmapd.conf Domain parameter is the same on server and client
    2. Server has an actual user with matching UID and GID to the client

    then on the client

    service nfs restart

    and remount shares if necessary

    • 1