using partimage with RAID

Background
As I am planning on a purchase of a 1080p cam, I will need my system to be up on the latest and greatest kernal and software to get the highest performance from Cinelerra. In that light, I'd like to backup my current Fedora 7 boot and root filesystems, just in case something goes wrong with the Fedora 9 install.

Partimage and My System
I will use partimage to backup these filesystems. Partimage will need to see source and destination filesystems. My first task is to figure out what I have. I built this system over a year ago and don't remember all the specifics of which physical drive has x or y filesystems. I could go back into my notes to find out how I partitioned my system, but that would be cheating. So let's see what the filesystem tells me.

The first thing I do is look at the output of df:
[mule@ogre ~]# df -m
Filesystem 1M-blocks Used Available Use% Mounted on
/dev/md0 457295 6720 426972 2% /
/dev/md2 469453 417004 28602 94% /mnt/videos
/dev/sda1 99 19 76 20% /boot
tmpfs 1007 0 1007 0% /dev/shm

I have two RAID devices, one mounted as my root partition (/dev/md0) and one mounted as my video storage (/dev/md2). Next, I see that /dev/sda1 is my boot partition. Finally, there is a filesystem defined for shared memory, though I am not concerned about saving the contents of that as it is RAM.

How It Works
Partimage backs up filesystems that are not mounted. But partimage is started from a bootable rescue disk, like Knoppix or SysRescCd. The twist here is that I am using RAID partitions. Thus, when I boot with one of these CDs, I will need to assemble my RAID drives in order to have a source to backup (my root filesystem) and a destination to write to (my /mnt/videos filesystem). Partimage will not use a mounted filesystem as a source, but I will need to mount the destination.

Assembling My RAID Drives
I have forgotten the configuration of my RAID drives, so I look at /etc/mdadm.conf to figure out what partitions and UUIDs make up my two RAID sets:
[mule@ogre ~]# cat /etc/mdadm.conf
# mdadm.conf written out by anaconda
DEVICE partitions
MAILADDR root
ARRAY /dev/md0 level=raid0 num-devices=2 uuid=c0d4b597:c33b3014:ab694cee:76920165
ARRAY /dev/md2 level=raid1 num-devices=2 UUID=1705b387:1c71d83e:364b60b4:fb0cc192

This tells me that my root partition (/dev/md0) is a stripe set (RAID0) and that the storage for my important stuff, all my videos in /mnt/video is mirrored (RAID1) in case of a failure. I'm glad I built the system this way, as I like the performance benefits of a stripe set for my root partition, but I would consider it tragic if I lost all my work. Therefore, I've mirrored the video drive on two drives in case of a failure.

Video Display Problem with Linux and NVidia Card
For some reason I have not figured out, I cannot see virtual consoles once I exit Gnome. This is due to some incompatibility between the NVidia 8800GT card and my Dell SC1430. This also effects the display when I boot with either Knoppix or SysRescCD. Using these tools, the screen goes black and I can't see any terminal sessions or virtual consoles. Therefore, in order to use the boot cd, I removed the NVidia card and booted using Dell's ATI ES1000 onboard video.

Booting with Knoppix
Once Knoppix is fully booted, I need to assemble my two RAID partitions. You can use either use the UUID or the super-minor number of each RAID set to do this. I chose the super-minor, as it was simpler.

Assemble the Source RAID set
Here I am assembling the source drive, my root filesystem:
root@Knoppix:/ramdisk/home/knoppix# modprobe md
root@Knoppix:/ramdisk/home/knoppix# mdadm --assemble -m 0 /dev/md0

Mount the Destination Partition
Since I want to store the backup image on the same mirrored drive set that holds my videos, I'll mount that partition as the destination for the partimage. Of course, I first have to create the mount point:
mkdir /mnt/videos
mount -t ext3 /dev/md2 /mnt/videos

Run Partimage to Backup Root Partition
I'll need three things to run partimage:
-an assembled RAID set of the source, my root/boot partitions, unmounted
-an assembled RAID set of the destination, mounted
-a compression method

Here's the partimage process:
1) Select the partition to save and give the backup a destination and name. Note that the "Save partition into an image file" is selected as the default behavior:


2) Select a compression method:


3) Give the backup image a description (optional):


4) Partimage takes a few minutes to gather information about large (500GB+ drives), but then displays basic information about the partition to be backed up:


5) Partimage starts the imaging process. I had about 6GB to backup:


6) Partimage took about 20 minutes to create the backup image:


Backup complete. The restore process is similar, but instead of backing up an image file as in Step 1 above, you'll choose the "Restore Partition from an image file" option.

Run Partimage for Boot Partition
Since my boot partition is small 128MB, creating a backup image shouldn't take very long. My boot partition is /dev/sda1


Now I should be ready to an upgrade to Fedora 9. One hurdle I already see: the Fedora 9 installation doesn't recognize pre-existing RAID sets. Yarg. Looks like I might have to blow away the existing stripe set that is home to my root partition. Let you know how that goes.

Update 11/17/2008
The Fedora 9 x86-64 install went well. Here are some of the natty details:
http://crazedmuleproductions.blogspot.com/2008/11/fedora-9-x86-64-install.html
end update

Good day,
The Mule

References
mdadm man page

A year later, ATI Linux drivers still suck

Folks, just in case you don't know, ATI's display drivers for Linux still suck, one year later:
/2006/09/ati-opengl-20-implementation.html
/2006/09/opengl-acceleration-for-cinelerra-not.html

Here's a bit of the latest pain:
https://init.linpro.no/pipermail/skolelinux.no/cinelerra/2007-October/012026.html

Here's another tale of woe (read starting with post #1014):
http://forums.fedoraforum.org/showthread.php?t=155503&page=102&pp=10

In the interest of having a clean system to start with, I reinstalled Fedora Core 6, 64-bit. I installed all Cinelerra source dependencies and attendent media players and apps as per this post (/2007/09/building-cinelerra-on-fc6-64-bit.html). I then made the very intelligent choice of backing up my system by using a Knoppix Bootable CD (www.knoppix.com) to load partimage and make an image of my system drive. For those who'd like to know how to do this, I will try to post a doc on what to do.
Update 2008/11/16
Here's how you can do this.
end update

This allows me to easily restore from image if anything went drastically wrong with the ATI install process. It is a good thing I did this.

After having the core softwares installed, I compiled Cinelerra and created a project by recording a screen capture with voiceover, some fades and a simple mask. This worked well, so I then decided to tackle building the 8.36.5 version of the ATI installer. I built the ATI rpms with the following command:
./ati-driver-installer-8.36.5-x86.x86_64.run --buildpkg Fedora/FC6
With the recent clean install of FC6 x86-64-bit, I was surprised to see that the build process actually worked! Previously, this build process failed. I speculate that the reason for the previous failure was that I kept my repositories consistent on this OS build. This means I tried not to mix rpm bases from more than two non-Fedora repositories: Dries and Livna, respectively. Refer to http://crazedmuleproductions.blogspot.com/2007/09/building-cinelerra-on-fc6-64-bit.html) for the detail. So having this build process work was unexpected. It gave me hope that I might have some resolution to my ATI woes.

I installed the created ATI rpms and shutdown the box. I popped in the VisionTek card and rebooted to init 3, full multi-user mode, without X enabled. I then ran the ATI configurator:
./aticonfig --initial -f

[sodo@ogre 8.36]# ls -l
total 65244
-rwxr-xr-x 1 root root 53331877 Oct 8 21:18 ati-driver-installer-8.36.5-x86.x86_64.run
-rw-r--r-- 1 root root 6469324 Oct 10 22:49 ATI-fglrx-8.36.5-1.fc6.x86_64.rpm
-rw-r--r-- 1 root root 3367465 Oct 10 22:49 ATI-fglrx-control-center-8.36.5-1.fc6.x86_64.rpm
-rw-r--r-- 1 root root 45017 Oct 10 22:49 ATI-fglrx-devel-8.36.5-1.fc6.x86_64.rpm
-rw-r--r-- 1 root root 3192548 Oct 10 22:49 ATI-fglrx-IA32-libs-8.36.5-1.fc6.x86_64.rpm
-rw-r--r-- 1 root root 309737 Oct 10 22:49 kernel-module-ATI-fglrx-2.6.18-1.2798.fc6-8.36.5-1.fc6.x86_64.rpm


This created a default fglrx /etc/X11/xorg.conf file. I started X and was pleasantly surprised to see both my monitors (Dell FP1901 and FP1907) come alive. I started the ATI Catalyst Display utility and was excited to see that OpenGL was indeed active. I switched from Clone mode (2 separate screens displaying the same thing) to Big Desktop mode, one large desktop. Excitedly, I wanted to see the behavior of xine and mplayer under 8.36.5, as I read some threads that lead me to believe I might get OpenGL without the xine crashes and mplayer sluggishness I had seen using 8.39.4 and 8.40.4. Unfortunately, it was not to be, as I loaded mplayer to see the same sluggishness on HDV content display. I then started xine and true to form, xine displayed the HDV content, but then promptly crashed X.

Ah well. At this point, I decided to restart the system, just to see if the restart improved conditions. When I restarted, I got the following error:
/etc/rc.d/rc.sysinit line 819: Segmentation fault

Oh boy. That does not look good. And the entire system has locked up..I can't even reboot. After a hard shutdown, I restarted, only to find the same error condition reappear. Google is again my best friend:
http://www.linuxforums.org/forum/servers/15670-help-segmentation-fault.html

So, it seems my choices are that:
1) my system memory is corrupt
2) grep is corrupt
3) I've been hacked

This is a new server with ECC memory, so I really doubt the memory has gone bad. But I'd rather be sure. Through the above Google find, I see that memtest86 (www.memtest86.com) is a solid program for testing your system memory that I haven't used before. The doc on the website is very good. I grabbed the ISO online and burned a copy to CD and let my machine churn for about three hours running through memory tests. Thank goodness, no memory errors were found. It seems that Mr. Brady knows his stuff! Thanks Chris!

Secondly, I tried to remark out the offending "for" loop within rc.sysinit. I needed to boot off a Knoppix (www.knoppix.com) CD to be able to assemble my software RAID partition, mount it and edit the file. Doing this and rebooting yielded the same results.

My third and final troubleshooting procedure was to remove and replace "grep" which is where the init loader failed. Again, I booted off the Knoppix CD, assembled and mounted my RAID. This time, however, I changed my root (chroot) partition in order the remove and reinstall grep via rpm and the Fedora install DVD. I did this, rebooted and received the same error.

At this point, I threw my hands up in the air and decided to reinstall my clean partimage image. Knoppix to the rescue again, and I restored the image of my clean install off a second drive I had on the system. A reboot later and I was back up and running. Praise the Lord!

So..what is the moral of this story, you might ask? It must be this, cause I can't think of anything else right now: Don't trust people over 30 and be sure that ATI will always disappoint you if you run Linux.

Harumph!
The Mule

migrated my FC6 system to faster disk

When I was on Fedora Core 4, I had been using a fast, 250GB Western Digital SATA drive as my main root partition. Since I live in both XP and Fedora worlds, I divided up the drive into the following partitions:
/dev/sda1: XP boot (40GB)
/dev/sda2: Fedora Core 4 /boot (128MB)
/dev/sda3: Fedora Core 4 / (root) (120GB)
/dev/sda4: unused
/dev/sda5: swap (6GB)
/dev/sda6: FAT32 (to transfer files in between Linux and XP) (60GB)

This configuration allows me to dual boot XP and FC easily, as well as transfer files in between the two OSs. Speaking of NTFS-ext2/3 transfers, I'm slowing phasing out the FAT32 partition for transfers because I have had success using ntfs-3g (http://www.ntfs-3g.org) to write to and read from my NTFS partitions. NTFS-3g has been very solid for reading and writing from Linux to NTFS.

Earlier this year, I installed Fedora Core 6 as a development/test system on a separate 40GB drive. Doing the install this way instead of an upgrade of FC4 meant that I didn't have to cripple the FC4 system in case anything went wrong with FC6. As it happens, Cinelerra on FC6 happens to be the most stable Cinelerra I've used these past two years, apart from an audio sync issue on rendered videos. I correct the sync problem using the Nudge feature on each audio track, detailed here:
/2007/05/nudge-avidemux2-and-reminder-about.html

Lo these past six months, I have been editing on FC6, albeit on a slower IDE drive, a 7200RPM Barracuda. The 250GB SATA with 16MB memory cache is quite a bit faster. So the goal was to move the boot/root of the FC6 system to the boot/root of the faster SATA drive.

LVM versus ext3
The first issue I encountered was that the default installation of FC6 automatically creates a Volume Group and Logical Volumes instead of plain old ext2/ext3 filesystems. My FC4 system used ext3 for boot/root, so my original plan was to do a simple partimage backup of the two FC6 filesystems. That idea would not work, as FC6 was on LVM and partimage doesn't recognize LVM partitions.

As an experiment (and because I wanted to get up and running quickly), I simplified the plan to install the new drive in the machine, mount the FC4 filesystems on the fast drive, delete the content on them and replace the content with the FC6 system files. I'd have to then tweak fstab and grub.conf appropriately on the updated drive to make the whole thing work.

The Plan
1) install both drives in the same machine with FC6 as the primary system,
2) mount the FC4 partitions of the fast drive in FC6 (/mnt/fc4boot & /mnt/fc4root),
3) remove all the files off of the FC4 boot/root filesystems,
4) copy the files from the FC6 boot/root parts to the FC4 partitions,
5) carefully tweak grub.conf and fstab to reference the new partition scheme
6) hope for the best on reboot

Here is where we had "a few issues" as an old boss of mine would say.

Problems!
I guess it is my cursory knowledge of the boot process that got me into trouble. The first issue after performing these four steps was the following error:
mount: could not find filesystem '/dev/root'
setuproot: moving /dev failed: No such file or directory
setuproot: error mounting /proc: No such file or directory
setuproot: error mounting /sys: No such file or directory
switchroot: mount failed: No such file or directory
Kernel panic - not syncing: Attempted to kill init!

Ouch! That doesn't look good. Following the advice of this thread:
http://www.linuxquestions.org/questions/showthread.php?t=497332

First, using SysRescCD, I verified my partition labels on the fast drive using e2label:
e2label /dev/hdN
where N is the Fedora partition

I double-checked my grub.conf and fstab:

/boot/grub/grub.conf
Here's the old entry:
title Fedora Core (2.6.19-1.2911.fc6)
root (hd0,0)
kernel /vmlinuz-2.6.19-1.2911.fc6 ro root=/dev/VolGroup00/LogVol00
initrd /initrd-2.6.19-1.2911.fc6.img

Here's the new entry:
title Fedora Core (2.6.19-1.2911.fc6)
root (hd0,1)
kernel /vmlinuz-2.6.19-1.2911.fc6 ro root=LABEL=/
initrd /initrd-2.6.19-1.2911.fc6.img

Note the changes in bold that I needed to enter in order to move the root from the first partition on the older, slow drive to the second partition on the faster drive. Also, LVM goes away to be replaced by the simpler naming scheme of the ext3 formatted partition.

/etc/fstab
Secondly, the fstab changes as well, from:
/dev/VolGroup00/LogVol00 / ext3 defaults 1 1
/dev/VolGroup00/LogVol01 swap swap defaults 0 0

To:
LABEL=/ / ext3 defaults 1 1
/dev/sda5 swap swap defaults 0 0

The /boot entry stays the same:
LABEL=/boot /boot ext3 defaults 1 2

The output of e2label showed that my fast drive partition labels matched those in grub.conf and fstab. So no smoking gun there.

The next thing suggested in the thread was to create mkinitrd, the initial ram disk the Linux kernel uses for system files. Oh boy. I've forgotten about this one. I knew I had the correct partition labels, but I needed a little more background on mkinitrd and these articles helped:
http://www.faqs.org/docs/Linux-mini/Loopback-Root-FS.html
http://www.opennet.ru/docs/HOWTO/Kernel-HOWTO-11.html+creating+initrd
http://www.ibm.com/developerworks/linux/library/l-initrd.html

Redhat/Fedora has a nice utility called mkinitrd that simplifies many of the steps mentioned in the IBM and HOWTO articles above. I regenerated the initial ramdisk image on the new boot partition using the following command:
mkinitrd ./initrd-2.6.19-1.2911.fc6.img 2.6.19-1.2911.fc6

OK. There were no errors on creation and the file is there and has data:
-rw------- 1 root root 2398566 Sep 9 11:52 /boot/initrd-2.6.19-1.2911.fc6.img

Cool. Now for the moment of truth. The reboot! I powered down and waited for the system to come back up. Thankfully, the kernel got beyond the panic and booted properly! Hooray! However, I did see some errors still:
No volume groups found
Volume group "VolGroup00" not found
Unable to access resume device (/dev/VolGroup00/LogVol01)

But, the system loads fine and Cinelerra and all my apps seem to work. So I will have to research this error further.

Also, I saw when I started Evolution, I got the following error:
Error while storing folder 'Inbox'

Researching this, I saw that there were inconsistencies in the index files that Evolution creates. The workaround is simple: delete any mail folders in ~./evolution/mail/local with an extension of ev.~summary. These are indexing files only and you can safely remove them. Reference:
https://bugs.launchpad.net/ubuntu/+source/evolution/+bug/27014

For the past couple of days, I have been editing and Cinelerra is performing well. I'm glad I went through this exercise. Though, I really need to learn more about how to backup and restore LVM partitions. I might have saved myself some pain.

cheers!
The Mule