Dell PowerVault NX3500 - Manual (Page 179)

NFS Write To Snapshot
Description An NFS user tries to modify a file located in a snapshot.
Cause NAS volume snapshots cannot be modified by design.
Workaround Snapshot data cannot be modified. A snapshot is an exact representation of the NAS
volume data at the time of its creation.
NFS Access Denied To A File Or Directory
Description User cannot access the NFS file or directory even though the user belongs to the
group owning the NFS object and the group members are permitted to perform the
operation.
Cause NFS servers (versions 2 and 3) use the Remote Procedure Call (RPC) protocol for
authentication of NFS clients. Most RPC clients have a limitation of up to 16 groups
passed to the NFS server. If a user belongs to more than 16 UNIX groups, as supported
by some UNIX flavors, some of the groups are not passed and are not checked by the
NFS server and thus the user's access may be denied.
Workaround A possible way to verify this problem is to use newgrp to temporarily change the
primary group of the user and thus ensure it is passed to the server.
The simple workaround, although not always feasible, is to remove the user from
unnecessary groups, leaving only 16 groups or less.
Troubleshooting NAS File Access And Permissions Issues
Cannot Change The Ownership Of A File Or A Folder
Description Every file on the NAS system is owned by either a
UNIX or NTFS user. Inability to change ownership is
treated differently, depending on whether the
access is native or non-native.
Cause The user is not authorized to perform the
ownership change.
Workaround An authorized user must perform this action.
Cannot Modify NAS Files
Description A user or an application cannot modify a file.
Cause
• The client cannot modify a file due to lack of
permissions on the file.
• The NAS volume has reached full capacity and
the file system denies any write requests,
including overwrites.
• The NAS volume is a target in a replication
relationship and is read only.
Workaround
• If the problem appears only on some files, this
is a permission issue. Verify that the user
account has modify permissions on the file or
use a different user account.
• If the problem is related to a specific NAS
volume:
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