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 25, 2009 28.Dt NFSCBD 8 29.Os 30.Sh NAME 31.Nm nfscbd 32.Tn NFSv4 33client side callback daemon 34.Sh SYNOPSIS 35.Nm nfscbd 36.Op Fl p Ar port_number 37.Op Fl P Ar client_principal 38.Sh DESCRIPTION 39.Nm 40runs on a client using 41.Tn NFSv4 42to handle callback requests from the NFSv4 server. 43If no 44.Nm 45is running, NFSv4 mounts will still work, but the server will never issue 46Open Delegations to the client. 47.Pp 48One callback server and one master server 49are always started. 50.Pp 51The following options are available: 52.Bl -tag -width Ds 53.It Fl p Ar port_number 54Specifies what port# the callback server should use. 55.It Fl P Ar client_principal 56Specifies the host based principal name to be used as the target for 57callbacks over RPCSEC_GSS. For KerberosV, it must be in the client's 58default keytab file. 59This client_principal should be the same one specified by the 60.Cm gssname 61argument being used by nfsv4 mounts. 62If you do not specify this argument, callbacks will still work over AUTH_SYS, 63which is what many extant servers use even for RPCSEC_GSS mounts, as of 2009. 64.El 65.Pp 66For example, 67.Dq Li "nfscbd -p 7654 -P root" 68starts the daemon to handle callbacks on port# 7654 and is using the host based 69principal root@<client-host>.<dns-domain> as the callback target. 70.Pp 71.Nm 72listens for service requests at the port 73defined by NFSV4_CBPORT in /usr/include/fs/nfs/nfs.h, unless 74.Fl p 75has been specified. 76For more information on what callbacks and Open Delegations do, see 77.%T "Network File System (NFS) Version 4 Protocol" , 78RFC3530 . 79.Pp 80The 81.Nm 82utility exits 0 on success or >0 if an error occurred. 83.Sh SEE ALSO 84.Xr nfsv4 4 , 85.Xr mount_nfs 8 86.Sh HISTORY 87First introduced with the experimental nfs client for NFSv4 support in 2009. 88