Set up TTL on process

UNIX Solaris
1

Is there a way to setup the TTL (Time To Live) on a process. We have many ssh processes that seem to just stack up. These processes do not need a static connection all the time and it might cause problems on our servers. Does anybody know how to setup the TTL on a process?

2

There is "ulimit -t" but it uses CPU time, not clock time. Using it is however likely a wrong approach. You might first try understanding why these ssh processes do stack up in the first place.

1 Like
3

I'm new to Solaris, how do I setup the "ulimit -t"?

4

"ulimit -t" is not Solaris specific. You set it that way:

$ ulimit -t 60

That would mean the process cannot exceed 1 minute of CPU time.

Note that it affects the shell where you set it and all its children processes.

5

This would affect all processes? Is there a way to just affect one process?

6

I didn't wrote that would affect all processes, only the shell where you set it and its own children processes. Another clarification: the limit is per process, not shared.

7

I'm a little confused. I need to set the value for just ssh processes in the shell. How would I do that?

8

Create a wrapper (eg: mySsh) setting this limit to a single ssh command:

#!/bin/ksh
ulimit -t 3600
ssh "$@"
9

I need to take baby steps. Where would I put this wrapper (eg: mySsh) and what does the

"$@"

mean? Also, is ther a way to see what the current ulimit is set?

10

Anywhere in your PATH.

all parameters

The default is unlimited:

ulimit -a
11

Here is a copy of my profile file:

server-root# cat profile
#ident  "@(#)profile    1.18    98/10/03 SMI"   /* SVr4.0 1.3   */

# The profile that all logins get before using their own .profile.

trap ""  2 3
export LOGNAME PATH

if [ "$TERM" = "" ]
then
        if /bin/i386
        then
                TERM=sun-color
        else
                TERM=sun
        fi
        export TERM
fi


#       Login and -su shells get /etc/profile services.
#       -rsh is given its environment in its .profile.

case "$0" in
-sh | -ksh | -jsh)

        if [ ! -f .hushlogin ]
        then
                #       Allow the user to break the Message-Of-The-Day only.
                trap "trap '' 2"  2
                /bin/cat -s /etc/motd
                trap "" 2
        fi
esac

umask 037
trap  2 3
TMOUT=900;export TMOUT
if [ `/usr/bin/id | grep -c 'uid=0'` -eq 1 ]
then
PS1=`uname -n`"-"`id | cut -d"(" -f2 | cut -d")" -f1`"# ";export PS1
else
PS1=`uname -n`"-"`id | cut -d"(" -f2 | cut -d")" -f1`"$ ";export PS1
fi
/usr/bin/mesg n 2> /dev/null

Where would you suggest I put the mySsh file and where and how in the profile file would I enter the path to the mySsh file?