1.\" Copyright (c) 2009 Rick Macklem, University of Guelph 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd April 21, 2017 28.Dt NFSUSERD 8 29.Os 30.Sh NAME 31.Nm nfsuserd 32.Nd load user and group information into the kernel for 33.Tn NFSv4 34services plus support manage-gids for all NFS versions 35.Sh SYNOPSIS 36.Nm nfsuserd 37.Op Fl domain Ar domain_name 38.Op Fl usertimeout Ar minutes 39.Op Fl usermax Ar max_cache_size 40.Op Fl verbose 41.Op Fl force 42.Op Fl manage-gids 43.Op Ar num_servers 44.Sh DESCRIPTION 45.Nm 46loads user and group information into the kernel for NFSv4. 47It must be running for NFSv4 to function correctly, either client or server. 48It also provides support for manage-gids and must be running on the server if 49this is being used for any version of NFS. 50.Pp 51Upon startup, it loads the machines DNS domain name, plus timeout and 52cache size limit into the kernel. It then preloads the cache with group 53and user information, up to the cache size limit and forks off N children 54(default 4), that service requests from the kernel for cache misses. The 55master server is there for the sole purpose of killing off the slaves. 56To stop the nfsuserd, send a SIGUSR1 to the master server. 57.Pp 58The following options are available: 59.Bl -tag -width Ds 60.It Fl domain Ar domain_name 61This option allows you to override the default DNS domain name, which 62is acquired by taking either the suffix on the machine's hostname or, 63if that name is not a fully qualified host name, the canonical name as 64reported by 65.Xr getaddrinfo 3 . 66.It Fl usertimeout Ar minutes 67Overrides the default timeout for cache entries, in minutes. 68The longer the 69time out, the better the performance, but the longer it takes for replaced 70entries to be seen. If your user/group database management system almost 71never re-uses the same names or id numbers, a large timeout is recommended. 72The default is 1 minute. 73.It Fl usermax Ar max_cache_size 74Overrides the default upper bound on the cache size. The larger the cache, 75the more kernel memory is used, but the better the performance. If your 76system can afford the memory use, make this the sum of the number of 77entries in your group and password databases. 78The default is 200 entries. 79.It Fl verbose 80When set, the server logs a bunch of information to syslog. 81.It Fl force 82This flag option must be set to restart the daemon after it has gone away 83abnormally and refuses to start, because it thinks nfsuserd is already 84running. 85.It Fl manage-gids 86This flag enables manage-gids for the NFS server 87.Xr nfsd 8 . 88When this is enabled, all NFS requests using 89AUTH_SYS authentication take the uid from the RPC request 90and uses the group list for that uid provided by 91.Xr getgrouplist 3 92on the server instead of the list of groups provided in the RPC authenticator. 93This can be used to avoid the 16 group limit for AUTH_SYS. 94.It Ar num_servers 95Specifies how many servers to create (max 20). 96The default of 4 may be sufficient. You should run enough servers, so that 97.Xr ps 1 98shows almost no running time for one or two of the slaves after the system 99has been running for a long period. Running too few will have a major 100performance impact, whereas running too many will only tie up some resources, 101such as a process table entry and swap space. 102.El 103.Sh SEE ALSO 104.Xr getgrent 3 , 105.Xr getgrouplist 3 , 106.Xr getpwent 3 , 107.Xr nfsv4 4 , 108.Xr group 5 , 109.Xr passwd 5 , 110.Xr nfsd 8 111.Sh HISTORY 112The 113.Nm 114utility was introduced with the NFSv4 experimental subsystem in 2009. 115.Sh BUGS 116The 117.Nm 118use 119.Xr getgrent 3 , 120.Xr getgrouplist 3 121and 122.Xr getpwent 3 123library calls to resolve requests and will hang if the servers handling 124those requests fail and the library functions don't return. See 125.Xr group 5 126and 127.Xr passwd 5 128for more information on how the databases are accessed. 129