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The {{{run-in-pagsh}}} script was written with the best intentions, but it tries to do many, many things (process backgrounding, pidfile management, etc), all in one script, and all in a black box.  Moreover, it is currently not supported by its author.  Lastly, its name does not actually describe what it does (you're already in a pagsh when you ssh in to mire!)

If {{{run-in-pagsh}}} works for you, great.  If you encounter problems, please '''first try running your daemon using "explicit" methods described below''' before filing a bug against AFS.  This is to ensure that the problem you've run into is actually a problem with AFS and not a problem with {{{run-in-pagsh}}}.

== Explicit Token Management ==

This is really simple.  You have two userids: your normal userid (we'll call this "{{{fred}}}") and your "daemon" userid (we'll call this "{{{fred.daemon}}}").  The first userid is "high security"; if one of our shellservers is broken into, it's unlikely that this account would be compromised.  The second userid is "low security": if there is a security breach on '''any of our machines, then all daemon accounts are instantly compromised'''.  It is extremely important to understand this before you take the steps outlined below.

First, you must grant your "daemon" userid permissions on any files that the background task needs.  For example,

{{{
  fsr sa ~/my_daemon_workspace/ fred.daemon all
}}}

Second, you need to start your daemon process via {{{k5start}}}.  Use the following command:

{{{
  k5start -qtUf /etc/keytabs/user.daemon/fred -- XXX YYY ZZZ
}}}

Where {{{XXX YYY ZZZ}}} is the command you want to run in the background.

This command will run your task ''in the foreground'', but with all the proper token magic you need.  Now all you need to do is apply the normal techniques (crontab, at, nohup, screen, etc) to run the command above in the background.  However, token management and backgrounding are separate issues; this page only deals with token management.

That's it!  Simple, huh?

== Troubleshooting ==

Here are some things to try if you find out that your tokens are expiring:

=== Make sure that you're starting the daemon properly ===

Make sure that you're starting the daemon properly; {{{k5start}}} should appear as the parent of your daemon process.  To check this, try

{{{
pstree -Gap `whoami`
}}}

=== Capture Logs ===

Add a {{{-v}}} to the {{{k5start}}} command and capture the output:

{{{
k5start -vqtUf /etc/keytabs/user.daemon/fred -- mydaemon &> /tmp/my-log
}}}

Note that the logs need to go into {{{/tmp}}} because you don't need tokens to write there.

=== Check the KDC ===

Figure out when your tokens are expiring (almost always exactly 10 hours after launching your daemon) and ask the root admins to check the KDC logs to see if there is even an ''attempt'' to renew the tickets at approximately that time.