SRV(4) SRV(4)
NAME
srv, srvold9p, 9fs, srvssh - start network file service
SYNOPSIS
srv [ -abcCemnq ] [ -s seconds ] [net!]system[!service] [
srvname [ mtpt ] ]
srvssh [ -r ] [ -R ] [ -s ] [ -u u9fspath ] system [ srvname
[ mtpt ] ]
9fs [net!]system [mountpoint]
srvold9p [ -abcCdF ] [ -p servicename ] [ -s | -m mountpoint
] [ -u user ] [ -x command | -n network-addr | -f file
]
DESCRIPTION
Srv dials the given machine and initializes the connection
to serve the 9P protocol. By default, it connects to the
`9fs' (9P) service, which for TCP is port 564. It then cre-
ates in /srv a file named srvname. Users can then mount (see
bind(1)) the service, typically on a name in /n, to access
the files provided by the remote machine. If srvname is
omitted, the first argument to srv is used. Option m
directs srv to mount the service on /n/system or onto mtpt
if it is given. Option q suppresses complaints if the /srv
file already exists. The a, b, c, C, and n options are used
to control the mount flags as in mount (see bind(1)). The e
option causes srv to treat system as a shell command to be
executed rather than an address to be dialed. The s option
causes srv to sleep for the specified number of seconds
after establishing the connection before posting and mount-
ing it. This is sometimes needed by srvssh.
The specified service must serve 9P. Usually service can be
omitted; when calling some non-Plan-9 systems, a service
such as u9fs must be mentioned explicitly.
The 9fs command does the srv and the mount necessary to make
available the files of system on network net. The files are
mounted on mountpoint, if given; otherwise they are mounted
on /n/system. If system contains `/' characters, only the
last element of system is used in the /n name.
9fs recognizes some special names, such as dump to make the
dump file system available on /n/dump. 9fs is an rc(1)
script; examine it to see what local conventions apply.
Srvssh is an rc(1) command that connects to a remote Unix
system via ssh(1) and starts u9fs(4). The -u option
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SRV(4) SRV(4)
specifies the path to the u9fs binary on the remote system.
(By default, an unrooted path of u9fs is used; if the binary
is in the path of the remote SSH server, you don't need the
-u option.) For information about the other options, see
the introductory comment in /rc/bin/srvssh. The arguments
are the same as srv.
Srvold9p is a compatibilty hack to allow Fourth Edition Plan
9 systems to connect to older 9P servers. It functions as a
variant of srv that performs a version translation on the 9P
messages on the underlying connection. Some of its options
are the same as those of srv; the special ones are:
-d Enable debugging.
-F Insert a special (internal) filter process to
the connection to maintain message boundaries;
usually only needed on TCP connections.
-p servicename
Post the service under srv(3) as
/srv/servicename.
-u user When connecting to the remote server, log in
as user. Since srvold9p does no authentica-
tion, and since new kernels cannot authenti-
cate to old services, the likeliest value of
user is none.
-x command Run command and use its standard input and
output as the 9P service connection. If the
command string contains blanks, it should be
quoted.
-n network-addr
Dial network-addr to establish the connection.
-f file Use file (typically an existing srv(3) file)
as the connection.
Srvold9p is run automatically when a cpu(1) call is received
on the service port for the old protocol.
EXAMPLES
To see kremvax's and deepthought's files in /n/kremvax and
/n/deepthought:
9fs kremvax
9fs hhgttg /n/deepthought
To mount as user none a connection to an older server
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SRV(4) SRV(4)
kgbsun:
srvold9p -u none -m /n/kgbsun -p kgbsun -n il!kgbsun
Other windows may then mount the connection directly:
mount /srv/kgbsun /n/kgbsun
To connect to an instance of the Unix server u9fs(4) started
via ssh(1):
srvssh unix
FILES
/srv/* ports to file systems and servers posted by srv and
9fs
SOURCE
/sys/src/cmd/srv.c
/rc/bin/9fs
/rc/bin/srvssh
/sys/src/cmd/srvold9p
SEE ALSO
bind(1), auth(2), dial(2), srv(3), exportfs(4), import(4),
ftpfs(4), u9fs(4)
BUGS
Srv does not explicitly report failures of auth_proxy (see
auth(2)); mount (see bind(1)) does.
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