sfssd_config(5)

NAME

sfssd_config - meta-server configuration

DESCRIPTION

sfssd_config configures sfssd, the server that accepts

connections for sfsrwsd and sfsauthd. sfssd_config can be used

to run multiple ``virtual servers'', or to run several versions

of the server software for compatibility with old clients.

Directives are:

BindAddr ip-addr [port]

Explicitly specifies the IP address and port on which

sfssd should listen for TCP connections. To listen on

INADDR_ANY

specified, sfssd will use the value of the SFS_PORT environment variable, if it exists and is non-zero, or else fall back to the
default port number of 4.
It is important to note the difference between speci

fying a port number with the SFS_PORT environment variable, and

with a BindAddr directive. See the description of the SFS_PORT

environment variable in the sfs_environ man page for more infor

mation.

When no BindAddr directive is specified, sfssd at

tempts to figure out the appropriate port number(s) to bind to

automatically. It does so by looking for DNS SRV records for the

current hostname (or SFS_HOSTNAME environment variable). This is

quite different from specifying BindAddr 0.0.0.0 0, which would

always bind port 4 or whatever is specified with the SFS_PORT en

vironment variable.

RevocationDir path

Specifies the directory in which sfssd should search

for revocation/redirection certificates when clients connect to

unknown (potentially revoked) self-certifying pathnames. The de

fault value is /var/sfs/srvrevoke. Use the command sfskey

revokegen to generate revocation certificates.

HashCost bits

Specifies that clients must pay for connections by

burning CPU time. This can help reduce the effectiveness of de

nial-of-service attacks. The default value is 0. The maximum

value is 22.

Server {* | @Location[,HostID]}

Specifies a section of the file that applies connec

tion requests for the self-certifying pathname @Location,HostID.

If ,HostID is omitted, then the following lines apply to any con

nection that does not match an explicit HostID in another Server.

The argument * applies to all clients who do not have a better

match for either Location or HostID.

Release {* | sfs-version}

Begins a section of the file that applies to clients

running SFS release sfs-version or older. * signifies arbitrari

ly large SFS release numbers. The Release directive does not do

anything on its own, but applies to all subsequent Service direc

tives until the next Release or Server directive.

Extensions ext1 [ext2 ...]

Specifies that subsequent Service directives apply on

ly to clients that supply all of the listed extension strings

(ext1, ...). Extensions applies until the next Extensions,

Release

Service srvno daemon [arg ...]

Specifies the daemon that should handle clients seek

ing service number srvno. SFS defines the following values of

srvno:

1. File server 2. Authentication server 3. Remote exe

cution 4. SFS/HTTP (not yet released)

Service srvno -u path
Operates as the above syntax of Service, only instead

of spawning a daemon, connects to the unix-domain socket speci

fied by path to communicate with an already running daemon. This

option may be useful when debugging SFS servers, as the server

for a particular service on a particular self-certifying pathname

can be run under the debugger and receive connections on the usu

al SFS port without interfering with other servers on the same

machine.

Service srvno -t host [port]
Specifies that sfssd should act as a ``TCP proxy'' for

this particular service, relaying any incoming connections to TCP

port port on host. If unspecified, port is the default SFS TCP

port 4.

This syntax is useful in a NATted environment. For

instance, suppose you have two SFS servers with addresses

10.0.0.2 and 10.0.0.3 on a private network, and one machine

10.0.0.1 with an externally visible interface 4.3.2.1. You can

use this proxy syntax to export the internal file systems. The

easiest way is to pick two DNS names for the new servers, but

point them at your outside server. For example:

server-a.mydomain.com. IN A 4.3.2.1
server-b.mydomain.com. IN A 4.3.2.1

Then, on your outside machine, you might have the fol

lowing sfssd_config file:

Server server-a.mydomain.com
Release *
Service 1 -t 10.0.0.2
Service 2 -t 10.0.0.2
Service 3 -t 10.0.0.2

Server server-b.mydomain.com
Release *
Service 1 -t 10.0.0.3
Service 2 -t 10.0.0.3
Service 3 -t 10.0.0.3

Then on each of the internal machines, be sure to

specify Hostname server-A.mydomain.com and Hostname

server-B.mydomain.com in sfsrwsd_config.

The default contents of sfssd_config is:

Server *
Release *
Service 1 sfsrwsd
Service 2 sfsauthd
Service 3 rexd

To disable the file server, you can copy this file to

/etc/sfs/sfssd_config and comment out the line Service 1 sfsrwsd.

To disable the remote login server, comment out the line for

rexd.

To run an SFS read-only service, you could specify the

lines:

Server *
Release *
Service 1 sfsrosd

Note that you may have only one program per service number

within a Release clause. For instance, you cannot run both

sfsrosd and sfsrwsd unless the programs appear in separate claus

es such as:

Server *
Release *
Service 1 sfsrwsd
Service 2 sfsauthd
Service 3 rexd

Server @snafu.lcs.mit.edu,xzfeqjnareyn2dhqxc

cd7wrk5m847rh2
Release *
Service 1 sfsrosd

To run a different server for sfs-0.6 and older clients,

you could add the lines:

Release 0.6
Service 1 /usr/local/lib/sfs-0.6/sfsrwsd

FILES

/etc/sfs/sfssd_config
/usr/local/share/sfs/sfssd_config

meta-server configuration

(Files in /etc/sfs supersede default versions in

/usr/local/share/sfs.)

SEE ALSO

dirsearch(1), newaid(1), rex(1), sfsagent(1), sfskey(1),

ssu(1), sfs_config(5), sfs_hosts(5), sfs_srp_params(5),

sfs_users(5), sfsauthd_config(5), sfscd_config(5),

sfsrosd_config(5), sfsrwsd_config(5), sfs_environ(7),

funmount(8), nfsmounter(8), sfsauthd(8), sfscd(8), sfsrosd(8),

sfsrwcd(8), sfsrwsd(8), sfssd(8), vidb(8)

The full documentation for SFS is maintained as a Texinfo

manual. If the info and SFS programs are properly installed at

your site, the command info SFS should give you access to the

complete manual.

For updates, documentation, and software distribution,

please see the SFS website at http://www.fs.net/.

AUTHOR

sfsdev@redlab.lcs.mit.edu

SFS 0.8pre 2006-07-20

SFSSD_CONFIG(5)