Friday, August 18, 2006

fsck automatically on reboot

Here's a nice little trick I found.

I had a couple of hard reboots, due to power failures and I wanted to have all the ext3 filesystems in my fstab to be checked during the next reboot. Here's what I did.

There's an option in tune2fs, -C, which allows one to manually set the mount count for an ext2/3 filesystem. By default, on my Gentoo installation, all the ext3 filesystems are checked automatically after 38 mounts or 180 days, whichever happens earlier. By using tune2fs, one can set the mount count of a filesystem to be greater than this value and the filesystem will be automatically checked when the system boots up next time..

I did a
tune2fs -C 50

for all the ext2/3 filesystems in my fstab and they were all checked upon the next reboot.

Another way of doing this would be to change number of days since the filesystem was last checked to be greater than that value of 180. This can be done with the -T option of tune2fs.

In case you're wondering, you can change the default values of the mount count or the day limit using the -c and -t options to tune2fs respectively. As always, check man tune2fs for details ;)

Tuesday, August 15, 2006

4294967294

Alright, by far the most amusing thing I've seen recently.

r00723r0 comes into #gentoo-amd64 complaining about his init scripts failing to start due to "too many links" in /var/lib/init.d.

Now, here's the fun and how people neglect the most basic of things..

So me and some other people in the channel take him on a tour that included re-emerging of baselayout, editing config files properly (especially /etc/conf.d/rc), checking the system clock, making his bash handle some pipelines.. ("find / -print 2>/dev/null | xargs ls -ld | tr -s ' ' | sort -t ' '+1 | head -n 50 | less" courtsey of codermattie) and a few reboots. Nothing works. We even wondered about a misconfigured kernel. But nope.

So then comes the most basic of things that was needed to be done. A simple ls -lR into /var/lib revealed this gem...

drwxr-xr-x 4294967294 root root 4096 Aug 15 06:26 init.d

And here's the response it got in the channel..

[Tue Aug 15 2006] [15:46:36] [r00723r0] i'm pretty sure it's my kernel
[Tue Aug 15 2006] [15:46:43] [floyd_n_milan] look at that link count on /var/lib/init.d!
[Tue Aug 15 2006] [15:46:49] [floyd_n_milan> drwxr-xr-x 4294967294 root root 4096 Aug 15 06:26 init.d
[Tue Aug 15 2006] [15:46:54] [r00723r0] wtf???
[Tue Aug 15 2006] [15:47:00] [r00723r0] how do i fix it
[Tue Aug 15 2006] [15:47:07] [codermattie] holy poo !
[Tue Aug 15 2006] [15:47:10] [codermattie] that's it !
[Tue Aug 15 2006] [15:47:15] [floyd_n_milan] yeah LOL
[Tue Aug 15 2006] [15:47:17] [r00723r0] wow
[Tue Aug 15 2006] [15:47:19] [r00723r0] lol
[Tue Aug 15 2006] [15:47:24] [r00723r0] owned
[Tue Aug 15 2006] [15:47:30] [codermattie] man, that's the freakin 32 bit limit !
[Tue Aug 15 2006] [15:47:35] [r00723r0] haha
[Tue Aug 15 2006] [15:47:38] [r00723r0] oops?

Right. So the simple solution was to boot from a livecd and do an fsck.jfs on that filesystem...

[Tue Aug 15 2006] [15:59:21] [r00723r0] AHHH
[Tue Aug 15 2006] [15:59:30] [r00723r0] incorrect link counts have been detected
[Tue Aug 15 2006] [15:59:35] [r00723r0] will correct

Yes!

So from now on, please remember to do the simple and the most basic things first :P Oh yeah, and always, always, be very very careful with etc-update!!! ;)

I must say though that, the origins of that 4294967294 are definitely worth exploring. :D



P.S. Here's the comment r00723r0 left on the original livejournal entry:

The origin is from me rebooting (obviously during fsck) because I forgot to compile in framebuffer support.


Nice post, might be my home page for a while :P

Sunday, August 13, 2006

Birdslave, I!

Hehehe, yeah that's right! I now have birds coming to ask me for things they need. :D

We have a small terrace attached to our flat. There are a few plants and stuff. There used to be many more plants, but the damned society objected. Anyway, that's a different matter.

So.. for a couple of years now, my dad has been placing two trays filled with water in the terrace for the birds to use. Every morning a pair of Robins and a Sunbird visit the tray and enjoy a nice bath. Then during the day quite a few Sparrows, Crows, Pigeons and an occasional pair of the rare Golden Oriols come looking for a nice drink.

Today, my parents had to catch an early train off to Talegaon. So the tray wasn't filled. At about 2 pm, this crow comes screaming into my bedroom window. I wondered what he was doing, because they never approach the window so openly. He was nearly inside the room. Then I realised what the problem was. I looked outside and for sure, the trays were empty. So I just filled them up and fellow shut up.

Hehehe, that was so sweet :D. Birdslave, I :D

P.S. I forgot to take snaps. I might do it later..

Thursday, August 10, 2006

Kubuntu on HP NX6125

Right.. that went great :D

Now I would have lost had I given up halfway through the process..

Oh, I'm talking about Linux right now. I was installing Kubuntu on this HP/Compaq NX6125 laptop. I got very much frustrated halfway through the installation because of the damned 3D acceleration. What happened is, during the initial upgrading of packages, apt installed a new version of the kernel 2.6.15-26-386. This version didn't have the linux-restricted-modules package associated with it. As a result, even with a proper 'aticonfig' version of the xorg.conf, I didn't get direct rendering. The simple solution was to boot with the older 2.6.15-23-386 kernel, which had the restricted modules installed.

Once direct rendering was working, I simply followed the wiki instructions and went on to install XGL and compiz. That was risk, because I had no idea whether XGL worked on the ATI Radeon XPRESS 200M 5955 (PCIE) card on the laptop. It turned out that XGL ran fine. Now that's pleasure! All the night's hard work bore fruit and what a fruit!

So now I'm off to edit the wiki page for Gentoo and update the Radeon XPRESS 200M 5955 (PCIE) section. And since I haven't slept the whole night, working on this thing for 12 hours straight and its nearly 7 am, I'll go to bed.. or maybe get some breakfast and then go to bed.

Btw, these links will definitely prove useful if you're installing Linux on this laptop:

Updates from HP: http://h18007.www1.hp.com/support/files/hpcpqnk/us/locate/64_6170.html#0
Kubuntu on NX6125: http://wuestenleer.de/ku/index.html
Gentoo on NX6125: http://gentoo-wiki.com/HARDWARE_HP_Compaq_nx6125