NFSUSERD(8)						    BSD System Manager's Manual 					       NFSUSERD(8)

NAME

     nfsuserd -- load user and group information into the kernel for NFSv4 services

SYNOPSIS

     nfsuserd [-domain domain_name] [-usertimeout minutes] [-usermax max_cache_size] [-verbose] [-force] [num_servers]

DESCRIPTION

     nfsuserd loads user and group information into the kernel for NFSv4.  It must be running for NFSv4 to function correctly, either client or
     server.

     Upon startup, it loads the machines DNS domain name, plus timeout and cache size limit into the kernel. It then preloads the cache with group
     and user information, up to the cache size limit and forks off N children (default 4), that service requests from the kernel for cache
     misses. The master server is there for the sole purpose of killing off the slaves.  To stop the nfsuserd, send a SIGUSR1 to the master
     server.

     The following options are available:

     -domain domain_name
	     This option allows you to override the default DNS domain name, which is acquired by taking either the suffix on the machine's host-
	     name or, if that name is not a fully qualified host name, the canonical name as reported by getaddrinfo(3).

     -usertimeout minutes
	     Overrides the default timeout for cache entries, in minutes. If the timeout is specified as 0, cache entries never time out. The
	     longer the time out, the better the performance, but the longer it takes for replaced entries to be seen. If your user/group database
	     management system almost never re-uses the same names or id numbers, a large timeout is recommended.  The default is 1 minute.

     -usermax max_cache_size
	     Overrides the default upper bound on the cache size. The larger the cache, the more kernel memory is used, but the better the perfor-
	     mance. If your system can afford the memory use, make this the sum of the number of entries in your group and password databases.
	     The default is 200 entries.

     -verbose
	     When set, the server logs a bunch of information to syslog.

     -force  This flag option must be set to restart the daemon after it has gone away abnormally and refuses to start, because it thinks nfsuserd
	     is already running.

     num_servers
	     Specifies how many servers to create (max 20).  The default of 4 may be sufficient. You should run enough servers, so that ps(1)
	     shows almost no running time for one or two of the slaves after the system has been running for a long period. Running too few will
	     have a major performance impact, whereas running too many will only tie up some resources, such as a process table entry and swap
	     space.

SEE ALSO

     getgrent(3), getpwent(3), nfsv4(4), group(5), passwd(5), nfsd(8)

HISTORY

     The nfsuserd utility was introduced with the NFSv4 experimental subsystem in 2009.

BUGS

     The nfsuserd use getgrent(3) and getpwent(3) library calls to resolve requests and will hang if the servers handling those requests fail and
     the library functions don't return. See group(5) and passwd(5) for more information on how the databases are accessed.

BSD
								  April 25, 2009							       BSD