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 6, 2019 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. 47For Kerberized NFSv4 mounts, it must be running on both client(s) and 48server for correct operation. 49For non-Kerberized NFSv4 mounts, this daemon must be running unless all 50client(s) plus the server are configured to put uid/gid numbers in the 51owner and owner_group strings. 52.Pp 53It also provides support for manage-gids and must be running on the server if 54this is being used for any version of NFS. 55.Pp 56Upon startup, it loads the machines DNS domain name, plus timeout and cache size 57limit into the kernel. 58It then preloads the cache with group and user information, up to the cache size 59limit and forks off N children (default 4), that service requests from the kernel 60for cache misses. 61The master server is there for the sole purpose of killing off the slaves. 62To stop the nfsuserd, send a SIGUSR1 to the master server. 63.Pp 64The following options are available: 65.Bl -tag -width Ds 66.It Fl domain Ar domain_name 67This option allows you to override the default DNS domain name, which 68is acquired by taking either the suffix on the machine's hostname or, 69if that name is not a fully qualified host name, the canonical name as 70reported by 71.Xr getaddrinfo 3 . 72.It Fl usertimeout Ar minutes 73Overrides the default timeout for cache entries, in minutes. 74The longer the 75time out, the better the performance, but the longer it takes for replaced 76entries to be seen. 77If your user/group database management system almost never re-uses the same names 78or id numbers, a large timeout is recommended. 79The default is 1 minute. 80.It Fl usermax Ar max_cache_size 81Overrides the default upper bound on the cache size. 82The larger the cache, the more kernel memory is used, but the better the performance. 83If your system can afford the memory use, make this the sum of the number of 84entries in your group and password databases. 85The default is 200 entries. 86.It Fl verbose 87When set, the server logs a bunch of information to syslog. 88.It Fl force 89This flag option must be set to restart the daemon after it has gone away 90abnormally and refuses to start, because it thinks nfsuserd is already 91running. 92.It Fl manage-gids 93This flag enables manage-gids for the NFS server 94.Xr nfsd 8 . 95When this is enabled, all NFS requests using 96AUTH_SYS authentication take the uid from the RPC request 97and uses the group list for that uid provided by 98.Xr getgrouplist 3 99on the server instead of the list of groups provided in the RPC authenticator. 100This can be used to avoid the 16 group limit for AUTH_SYS. 101.It Ar num_servers 102Specifies how many servers to create (max 20). 103The default of 4 may be sufficient. 104You should run enough servers, so that 105.Xr ps 1 106shows almost no running time for one or two of the slaves after the system 107has been running for a long period. 108Running too few will have a major performance impact, whereas running too many 109will only tie up some resources, such as a process table entry and swap space. 110.El 111.Sh SEE ALSO 112.Xr getgrent 3 , 113.Xr getgrouplist 3 , 114.Xr getpwent 3 , 115.Xr nfsv4 4 , 116.Xr group 5 , 117.Xr passwd 5 , 118.Xr nfsd 8 119.Sh HISTORY 120The 121.Nm 122utility was introduced with the NFSv4 experimental subsystem in 2009. 123.Sh BUGS 124The 125.Nm 126use 127.Xr getgrent 3 , 128.Xr getgrouplist 3 129and 130.Xr getpwent 3 131library calls to resolve requests and will hang if the servers handling 132those requests fail and the library functions don't return. 133See 134.Xr group 5 135and 136.Xr passwd 5 137for more information on how the databases are accessed. 138