The rpc.nfsd program implements the user level part of the NFS
service. The main functionality is handled by the nfsd kernel module.
The user space program merely specifies what sort of sockets the
kernel service should listen on, what NFS versions it should support,
and how many kernel threads it should use.
The rpc.mountd server provides an ancillary service needed to satisfy
mount requests by NFS clients.
-d or --debug
enable logging of debugging messages
-H or --host hostname
specify a particular hostname (or address) that NFS requests
will be accepted on. By default, rpc.nfsd will accept NFS
requests on all known network addresses. Note that lockd
(which performs file locking services for NFS) may still
accept request on all known network addresses. This may
change in future releases of the Linux Kernel. This option can
be used multiple time to listen to more than one interface.
-p or --port port
specify a different port to listen on for NFS requests. By
default, rpc.nfsd will listen on port 2049.
-r or --rdma
specify that NFS requests on the standard RDMA port
("nfsrdma", port 20049) should be honored.
Listen for RDMA requests on an alternate port - may be a
number or a name listed in /etc/services.
-N or --no-nfs-version vers
This option can be used to request that rpc.nfsd does not
offer certain versions of NFS. The current version of rpc.nfsd
can support major NFS versions 2,3,4 and the minor versions
4.1 and 4.2.
-s or --syslog
By default, rpc.nfsd logs error messages (and debug messages,
if enabled) to stderr. This option makes rpc.nfsd log these
messages to syslog instead. Note that errors encountered
during option processing will still be logged to stderr
regardless of this option.
-T or --no-tcp
Disable rpc.nfsd from accepting TCP connections from clients.
-U or --no-udp
Disable rpc.nfsd from accepting UDP connections from clients.
-V or --nfs-version vers
This option can be used to request that rpc.nfsd offer certain
versions of NFS. The current version of rpc.nfsd can support
major NFS versions 2,3,4 and the minor versions 4.1 and 4.2.
-L or --lease-time seconds
Set the lease-time used for NFSv4. This corresponds to how
often clients need to confirm their state with the server.
Valid range is from 10 to 3600 seconds.
-G or --grace-time seconds
Set the grace-time used for NFSv4 and NLM (for NFSv2 and
NFSv3). New file open requests (NFSv4) and new file locks
(NLM) will not be allowed until after this time has passed to
allow clients to recover state.
nproc specify the number of NFS server threads. By default, eight
threads are started. However, for optimum performance several
threads should be used. The actual figure depends on the
number of and the work load created by the NFS clients, but a
useful starting point is eight threads. Effects of modifying
that number can be checked using the nfsstat(8) program.
Note that if the NFS server is already running, then the options for
specifying host, port, and protocol will be ignored. The number of
processes given will be the only option considered, and the number of
active nfsd processes will be increased or decreased to match this
number. In particular rpc.nfsd 0 will stop all threads and thus
close any open connections.
Many of the options that can be set on the command line can also be
controlled through values set in the [nfsd] section of the
/etc/nfs.conf configuration file. Values recognized include:
The number of threads to start.
host A host name, or comma separated list of host names, that
rpc.nfsd will listen on. Use of the --host option replaces
all host names listed here.
The grace time, for both NFSv4 and NLM, in seconds.
The lease time for NFSv4, in seconds.
port Set the port for TCP/UDP to bind to.
rdma Set RDMA port. Use "rdma=nfsrdma" to enable standard port.
UDP Enable (with "on" or "yes" etc) or disable ("off", "no") UDP
TCP Enable or disable TCP support.
vers2vers3vers4 Enable or disable a major NFS version. 3 and 4 are normally
enabled by default.
Setting these to "off" or similar will disable the selected
minor versions. Setting to "on" will enable them. The
default values are determined by the kernel, and usually minor
versions default to being enabled once the implementation is