[Server-devel] Anaconda does not clear /var/lock/subsys - service $svc condrestart start services

[Martin Langhoff]

In the course of diagnosing a strange problem that seems to happen
only on some anaconda-driven upgrades, I found that -- unlike the
normal boot process -- there is nothing in anaconda that clears
/var/lock/subsys.

(Note - this applies to the Fedora 9 based OLPC XS. Perhaps this is
known and fixed?)

This completely fools the `service <svc> condrestart` lines in %post,
and can lead to various hard to debug problems. In my case, I am
seeing corrupt databases with ejabberd  (which has an admittedly
brittle db scheme).

To test this, touch /var/lock/subsys/foo; sync ; power off the machine
and run an anaconda upgrade. You'll see that while packages are being
installed, the file remains there. If that had been
'/var/lock/subsys/ejabberd' you'd have a corrupt DB. Don't feel left
out though, if you want one, I can give you mine :-)

This may sound weird -- don't you expect a clean shutdown before an
upgrade? -- but in OLPC School Servers in the field get quite a bit of
rough handling. The ones I work with sure get most of their poweroffs
via the "powercable yanking" scheme, so I get to see these problems
here before they happen in the field.

IOWs reliability in the face of strange conditions _is_ desirable, and
important.

 - Is this known, or fixed?
 - Is there a reasonable workaround? kickstart is not used for
upgrades, even if it was, %pre happens to early, %post happens too
late.

Would the right place to clear (or complain about!) /var/lock/subsys
would be upgrade.py: upgradeMountFilesystems()?

cheers,




m
-- 
 martin.langhoff at gmail.com
 martin at laptop.org -- School Server Architect
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