[lustre-discuss] root squash config not working anymore

[Jane Liu]

Hi,

We are facing an issue with root squash in our Lustre file system. It 
used to work perfectly, but recently, it stopped taking effect. I've 
been trying to have root access on our MDS server to access the Lustre 
file system, but none of the configurations I've tried seem to work 
anymore.

Here are the settings I've tried so far:

    (1) mdt.myfs01-MDT0000.root_squash=0:0

    (2) mdt.myfs01-MDT0000.nosquash_nids=20.42.34.79 at tcp
     mdt.myfs01-MDT0000.root_squash=99:99

    (3) mdt.myfs01-MDT0000.root_squash=0:0
     mdt.myfs01-MDT0000.nosquash_nids=20.42.34.79 at tcp

Despite all these attempts, I still face a 'Permission denied' error 
when trying to create a regular file in lustre using root account.

Here is an example:

[root at myfsmds01 /]# mount -t lustre 20.42.34.79 at tcp:/myfs01 /mnt/
[root at myfsmds01 /]# lctl get_param mdt.*.*squa*
mdt.myfs01-MDT0000.nosquash_nids=20.42.34.79 at tcp
mdt.myfs01-MDT0000.root_squash=0:0
[root at myfsmds01 /]# cd /mnt
[root at myfsmds01 mnt]# mv /tmp/aaa /tmp/test.dat
[root at myfsmds01 mnt]# cp /tmp/test.dat ./test18
cp: cannot create regular file './test18': Permission denied

[root at myfsmds01 mnt]# sestatus
SELinux status:                 disabled

This issue started recently, and I haven't made any significant changes 
to the system. Are there any known problems with root squash that I 
might have missed?

Thanks in advance,
Jane