.fp 5 CW

.de L \" literal font

.ft 5

.it 1 }N

.if !\\$1 \&\\$1 \\$2 \\$3 \\$4 \\$5 \\$6

..

.de LR

.}S 5 1 \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6"

..

.de RL

.}S 1 5 \& "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6"

..

.de EX \" start example

.ta 1i 2i 3i 4i 5i 6i

.PP

.RS

.PD 0

.ft 5

.nf

..

.de EE \" end example

.fi

.ft

.PD

.RE

.PP

..

.TH SSD 8

.SH NAME \" @(#)ssd.8 (gsf@research.att.com) 04/01/94

ssd \- network system status demon

.SH SYNOPSIS

ssd [

.I host

]

.SH DESCRIPTION

.I ssd

is a local network system status demon that generates data for

.IR ss (1)

and the

.IR cs (3)

routine

.LR csstat .

There is one

.I ssd

demon per host.

The status information for each host is maintained in a directory that

is accessible by all hosts.

Network file system traffic is minimized by placing the information in the

.B atime

and

.B mtime

.IR stat (2)

fields.

Demon update frequencies are also randomized to avoid network traffic spikes.

.PP

Demons are started by explicit calls to either

.IR ss (1)

or

.LR csstat .

However, it wouldn't hurt to place

.EX

ss . >/dev/null 2>&1

.EE

in

.LR rc.local .

.PP

If the

.I host

argument is given then a demon is started on that host.

.PP

If the optional command

.I ssd.idle

is placed in the same directory as

.I ssd

then it is executed, with the current hostname as the first argument,

to determine the host idle time.

.I ssd.idle

is under complete control of the local installation and is not supplied

in the standard distribution.

.I ssd

must be restarted in order for it to recognize a newly added

.IR ssd.idle .

.I ssd

reads the first line of output from

.I ssd.idle

to determine the idle time:

.RS

.TP

.L busy

The idle time is set to

.IR 0 .

.TP

.L free

The idle time is set to a large value.

.TP

.L idle

The number of seconds since the last idle time check is added to

the previous idle time value.

.TP

.I seconds

The idle time is set to

.IR seconds .

.RE

.PP

For any other value

.I ssd

calculates the idle time using the default algorithm.

.SH CAVEATS

It may take a minute for a demon to recognize that another

demon is already running.

Because the local demon may be initiated by a status request

it may also take a minute for the status routine to recognize that the

local host is up.

.PP

The status information is placed in a directory that must be accessible

from all hosts on the local network.

The mount permissions on this directory should be tuned to prevent

hosts from hanging when the host servicing the directory is down.

The status information for

.I host

is placed in the file

.BI share/lib/ss/ host.

The demon for

.I host

can be killed by simply removing (\f5rm -f\fP) the

.BI share/lib/ss/ host

file.

.SH FILES

.TP 2i

.B share/lib/ss/.log

demon error log

.TP 2i

.BI share/lib/ss/ host

status for

.I host

.SH "SEE ALSO"

ss(1), cs(3)