cron FIFO in mounted spool filesystem

[Bill Blue]

In article <1654 at ispi.COM> jbayer at ispi.COM (Jonathan Bayer) writes:
>I admit it is not the best, but is do-able.  What you have to do is to
>create the /usr/spool/cron directory structure on the root filesystem,
>as well as having it on the mounted filesystem.  What is a pain is
>making sure that both sets of directories are identical, so when you
>boot up cron sees a correct file.  I would suggest doing it in one of
>two places:
>
>	1.  Modify the shutdown script to unmount the filesystem, mount 
>	    it again as /u, and do a "copy -omr /u/cron /usr/spool/cron"
>
>	2.  Modify the rc.d/2/mntfs to first mount the directory in /u,
>	    then do a similar copy as # 1, then have a script go through
>	    the /usr/spool/cron/crontabs and do a "crontab $..." in
>	    order to tell cron about any possible changes.
>
>I would really recommend doing both of these steps in order to avoid
>missing anything.  The only problem with # 2 is that it might miss some
>"at" jobs.

Why on earth do all this stuff?

>BTW, since cron is started _just_ before the filesystems are mounted,
>would there be a big problem in starting cron _after_ they are mounted? 
>I realize that the /etc/rc.d directories are set up in a fairly logical
>order, but that order could be moved around a bit without any real
>problems.

Just move the cron startup to rc.d/8/userdef.  It really doesn't
matter that cron is started up just after the mount.  Here on crash,
I have the entire /usr/spool hierarchy on a separate mount.  There
is no need for another 'hidden' /usr/spool to be there before the
real one gets mounted.  Just mount, start cron, and go on your way.
Nothing in single user mode without the mount mounted misses it.

I did it this way for a couple of reasons.  For one, it keeps all the
transient spool stuff from fragmenting the root filesystem.  Those who
optimize the harddrives for maximum throughput, will realize how badly
fragmentation affects performance.  Having a separate /usr/spool helps
a lot to maintain / performance.  It also gives you the flexibility
of growing that space as your spool demands increase, without the
need of moving the root files around.

--Bill