# nfsd

## NAME



           rpc.nfsd - NFS server process
    


## SYNOPSIS



           **/usr/sbin/rpc.nfsd [**_options_**] nproc**
    


## DESCRIPTION



           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.
    


## OPTIONS



           **-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 times to listen to more
                  than one interface.
    
           **-S  or  --scope scope**
                  NFSv4.1 and later require the server to report a "scope"
                  which is used by the clients to detect if two connections
                  are to the same server.  By default Linux NFSD uses the
                  host name as the scope.
    
                  It is particularly important for high-availablity
                  configurations to ensure that all potential server nodes
                  report the same server scope.
    
           **-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.
    
           **--rdma=**_port_
                  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 3,4 and the minor
                  versions 4.0, 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  --tcp**
                  Instruct the kernel nfs server to open and listen on a TCP
                  socket. This is the default.
    
           **-T  or  --no-tcp**
                  Instruct the kernel nfs server not to open and listen on a
                  TCP socket.
    
           **-u  or  --udp**
                  Instruct the kernel nfs server to open and listen on a UDP
                  socket.
    
           **-U  or  --no-udp**
                  Instruct the kernel nfs server not to open and listen on a
                  UDP socket. This is the default.
    
           **-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 3,4 and the minor versions
                  4.0, 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.
    


## CONFIGURATION FILE



           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:
    
           **threads**
                  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.
    
           **scope** Set the server scope.
    
           **grace-time**
                  The grace time, for both NFSv4 and NLM, in seconds.
    
           **lease-time**
                  The lease time for NFSv4, in seconds.
    
           **port** Set the port for TCP/UDP to bind to.
    
           **rdma** Enable RDMA port (with "on" or "yes" etc) on the standard
                  port ("nfsrdma", port 20049).
    
           **rdma-port**
                  Set an alternate RDMA port.
    
           **UDP** Enable (with "on" or "yes" etc) or disable ("off", "no")
                  UDP support.
    
           **TCP** Enable or disable TCP support.
    
           **vers3**
    
           **vers4** Enable or disable **all** NFSv4 versions.  All versions are
                  normally enabled by default.
    
           **vers4.1**
    
           **vers4.2**
                  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 sufficiently complete.
    


## NOTES



           If the program is built with TI-RPC support, it will enable any
           protocol and address family combinations that are marked visible
           in the **netconfig** database.
    


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