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add the debian-ubuntu-battery-skip-fsck-bug blogentry

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Signed-off-by: Nico Schottelius <nico@ikn.schottelius.org>
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Nico Schottelius 2009-10-06 21:43:52 +02:00
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[[!meta title="Ubuntu and Debian skip fsck on battery - a bug"]]
Everytime I go through the init scripts or init configurations
of the "traditional" (as in having a sequential order and/or
using shell scripts) init systems, there are interesting things to find:
Not only that probably half of the boottime could be saved if people
move the "if system has x, do y" stuff out of the init system and make
it part of the configuration process, no.
There are also a lot of other interesting quirks within the init configuration,
like this one:
on_ac_power >/dev/null 2>&1
if [ "$?" -eq 1 ]
then
log_warning_msg "On battery power, so skipping file system check."
rootcheck=no
fi
That part is shameless stolen from ***S20checkroot.sh***,
Ubuntu Jaunty (9.04), but it can also be found in Debian.
So if the system is running on battery, this configuration will skip
the filesystem check.
Now imagine your filesystem **needs** to be checked, because the
user space program ***fsck*** replays the journal and marks the
filesystem as clean. Furthermore, assume that without this filesystem
check the filesystem cannot be mounted read write.
That is exactly what is done by ***fsck.jfs***, the filesystem check
for JFS filesystems.
So if you are running Debian or Ubuntu with JFS on the root filesystem,
your system crashed the last time and you bootup on battery the bootup
process will fail, because the root filesystem cannot be mounted
read write.
Perhaps the authors idea of these lines was to skip senseless
filesystem checks for ext{2,3,4}, which occur after a certain
amount of time. But as it can be seen, this "fix" introduced
a new bug.
Dear Debian and Ubuntu developers:
Please do not skip the filesystem check.
All the users with JFS on / of their notebook will thank you!
I would have fixed that in Debian myself, if there was a
"get a fix integrated in 5 minutes" approach.
But after reading Debian documentation for some hours I did not find it.
If you find that way [[let me know|about]] and I'll write an article
"How to fix a Debian package in 5 minutes" plus provide a patch
to solve this init misconfiguration issue.
[[!tag unix]]