Sun's web pages contain substantial information about NFS services; search for an NFS Administration Guide or NFS Server Performance and Tuning Guide for the version of Solaris you are running. The
man page contains specific information about export options.
If NFS is not working at all, try the following:
- Make sure that the NFS server daemons are running. In particular,
rarpd. If the daemons are not running, they can be started
/etc/init.d/nfs.server start. See
below for information on NFS-related
- Check the
/etc/dfs/dfstab and type
showmount -e to see which filesystems are currently exported,
and to whom.
showmount -a shows who the server believes
is actually mounting which filesystems.
- Make sure that your name service is translating the server and
client hostnames correctly on both ends. Check the server logs to
see if there are messages regarding failed or rejected mount attempts;
check to make sure that the hostnames are correct in these messages.
- Make sure that the
/etc/net/*/hosts files on both
ends report the correct hostnames. Reboot if these have to be edited.
If you are dealing with a performance issue, check
- Increase the number of
nfsd threads in
/etc/init.d/nfs.server if the problem is that requests
are waiting for a turn. Note that this does increase memory useage
by the kernel, so make sure that there is enough RAM in the server
to handle the additional load.
- Where possible, mount filesystem with the ro option to prevent
additional, unnecessary attribute traffic.
- If attribute caching does not make sense (for example, with a
mail spool), mount the filesystem with the
reports a high
may need to be increased (if the attributes do not change too often).
nfsstat reports on
most NFS-related statistics. The
page includes information on tuning suggestions for different types
of problems that can be revealed with
If these steps do not resolve the issue, structural changes may be
cachefs can be used to push some of the load from
the NFS server onto the NFS clients. To be useful,
should be used to increase
maxfilesize for the cache to
a value high enough to allow for the caching of commonly-used files.
(The default value is 3 Mb.)
When a client makes a request to the NFS server, a file handle is
returned. The file handle is a 32 byte structure which is interpreted
by the NFS server. Commonly, the file handle includes a file
system ID, inode number and the generation number of the inode.
(The latter can be used to return a "stale file handle" error
message if the inode has been freed and re-used between client
If a response is not received for a request, it is resent, but with
an incremented xid (transmission ID). This can happen because of
congestion on the network or the server, and can be observed with
a snoop session between server and client.
The server handles retransmissions differently depending on whether
the requests are idempotent (can be executed several times without
ill effect) or nonidempotent (cannot be executed several times).
Examples of these would include things like reads and getattrs
versus writes, creates and removes. The system maintains a cache
of nonidempotent requests so that appropriate replies can be
The following daemons play a critical role in NFS service:
- biod: On the client end, handles asynchronous I/O for blocks of
- nfsd: Listens and responds to client NFS requests.
- mountd: Handles mount requests.
- lockd: Network lock manager.
- statd: Network status manager.