Using the shareall Command

This command shares all file systems that are listed in a local file:

# shareall /etc/dfs/special_dfstab

unshareall Command

This command makes all currently shared resources unavailable. The -F FSType option selects a list of file-system types that are defined in /etc/dfs/fstypes. This flag enables you to choose only certain types of file systems to be unshared. The default file system type is defined in /etc/dfs/fstypes. To choose specific file systems, use the unshare command.

Using the unshareall Command

This example should unshare all NFS-type file systems:

# unshareall -F nfs

showmount Command

This command displays one of the following:

• All clients that have remotely mounted file systems that are shared from an NFS server

• Only the file systems that are mounted by clients

• The shared file systems with the client access information

The command syntax is as follows:

showmount [ -ade ] [ hostname ]

If hostname is not specified the local host is queried.

Using the showmount Command

This command lists all clients and the local directories that the clients have mounted.

# showmount -a bee
lilac:/export/share/man
lilac:/usr/src
rose:/usr/src
tulip:/export/share/man

This command lists the directories that have been mounted.

# showmount -d bee
/export/share/man
/usr/src

This command lists file systems that have been shared.

# showmount -e bee
/usr/src								(everyone)
/export/share/man					eng

setmnt Command

This command creates an /etc/mnttab table. The mount and umount commands consult the table. Generally, you do not have to run this command manually, as this command runs automatically when a system is booted.

Other Useful Commands

These commands can be useful when troubleshooting NFS problems.

nfsstat Command

You can use this command to gather statistical information about NFS and RPC connections. The syntax of the command is as follows:

nfsstat [ -cmnrsz ]

If no options are supplied on the command line, the -cnrs options are used.

Gathering server-side statistics can be important for debugging problems when new software or new hardware is added to the computing environment. Running this command a minimum of once a week, and storing the numbers, provides a good history of previous performance.

Using the nfsstat Command

# nfsstat -s

Server rpc:
Connection oriented:
calls      badcalls   nullrecv   badlen      xdrcall    dupchecks  dupreqs
11420263   0          0          0           0          1428274    19
Connectionless:
calls      badcalls   nullrecv   badlen      xdrcall    dupchecks  dupreqs
14569706   0          0          0           0          953332     1601

Server nfs:
calls      badcalls
24234967   226
Version 2: (13073528 calls)
null       getattr    setattr    root        lookup     readlink   read
138612 1%  1192059 9% 45676 0%   0 0%        9300029 71% 9872 0%   1319897 10%
wrcache    write      create     remove      rename     link       symlink
0 0%       805444 6%  43417 0%   44951 0%    3831 0%    4758 0%    1490 0%
mkdir      rmdir      readdir    statfs
2235 0%    1518 0%    51897 0%   107842 0%
Version 3: (11114810 calls)
null       getattr    setattr    lookup      access     readlink   read
141059 1%  3911728 35% 181185 1% 3395029 30% 1097018 9% 4777 0%   960503 8%
write      create     mkdir      symlink     mknod      remove     rmdir
763996 6%  159257 1%  3997 0%    10532 0%    26 0%      164698 1%  2251 0%
rename     link       readdir    readdirplus fsstat     fsinfo     pathconf
53303 0%   9500 0%    62022 0%   79512 0%    3442 0%    34275 0%   3023 0%
commit    
73677 0%  

Server nfs_acl:
Version 2: (1579 calls)
null       getacl     setacl     getattr     access    
0 0%       3 0%       0 0%       1000 63%    576 36%   
Version 3: (45318 calls)
null       getacl     setacl    
0 0%       45318 100% 0 0%

The previous listing is an example of NFS server statistics. The first five lines relate to RPC and the remaining lines report NFS activities. In both sets of statistics, knowing the average number of badcalls or calls and the number of calls per week can help identify a problem. The badcalls value reports the number of bad messages from a client. This value can point out network hardware problems.

Some of the connections generate write activity on the disks. A sudden increase in these statistics could indicate trouble and should be investigated. For NFS version 2 statistics, the connections to note are setattr, write, create, remove, rename, link, symlink, mkdir, and rmdir. For NFS version 3 statistics, the value to watch is commit. If the commit level is high in one NFS server as compared to another almost identical server, check that the NFS clients have enough memory. The number of commit operations on the server grows when clients do not have available resources.