PowerScale: When an NFS alias is made for a parent directory, exported subdirectories show in showmount -e from the client side
Summary: When an NFS alias is made for a parent directory, exported subdirectories are shown in showmount -e from the client side.
Symptoms
Have parent and subdirectory exported:
# isi nfs exports list ID Zone Paths Description -------------------------------------- 1 System /ifs/nfs 2 System /ifs/nfs/test -------------------------------------- Total: 2
Create an alias for the parent:
# isi nfs aliases list Zone Name Path -------------------------- System /testAlias /ifs/nfs -------------------------- Total: 1
Showmount -e from the client shows that unexpected paths returned:
[root@centos ~]# showmount -e x.x.x.x Export list for x.x.x.x: /testAlias/test x.x.x.x <<<<< subdirectory test is returned as part of the alias /testAlias x.x.x.x /ifs/nfs/test x.x.x.x /ifs/nfs x.x.x.x
Cause
Resolution
To prevent aliases from appearing in showmount -e, disable the setting on the PowerScale so only full paths are returned. Clients would still be able to mount the alias, but it would prevent dual paths from being returned which may cause confusion in some environments.
Please note this does require a restart of NFS across the cluster for this change to take effect.
To disable the return of aliased paths in showmount:
# isi_gconfig registry.Services.lwio.Parameters.Drivers.nfs.MountdAliasesInShowmountE=0
Restart NFS across the cluster (can be ran node by node instead of running with isi_for_array if preferred:
# isi_for_array -s '/usr/likewise/bin/lwsm restart onefs_nfs'
Now showmount -e from the client only shows the full paths and no longer the aliases:
[root@centos ~]# showmount -e x.x.x.x Export list for x.x.x.x: /ifs/nfs/test x.x.x.x /ifs/nfs x.x.x.x