Software RAID and mdadm

[johnd]

Hi

 

I am trying to install Mandriva 2008.1 onto a dual drive RAID system. I can make the same RAID partitions on each drive but when I try to add them to RAID, I get told that mdadm is not installed. Then:

 

1. I checked and found that it is installed.

2. Tried running as the install routine as root with the same result.

3. Then noticed that the mdadm service was not running - I could not start it ether from the GUI or with service mdadm start.

 

So - is there any way I can install 2008.1 onto software RAID?

 

Thanks

John

[ianw1974]

Are you using a One LiveCD to install or the full CD/DVD installation set? I've noticed this problem on Mandriva 2009 RC1 with the LiveCD and cannot get it to do it either. Although I know that with previous Mandriva systems like 2006 and 2007 that it worked for me - however the only difference was I used CD/DVD installation sets and not the One LiveCD.

 

PS: welcome to the board

[johnd]

Are you using a One LiveCD to install or the full CD/DVD installation set?

Thanks for the welcome - yes - using the LiveCD.

[ianw1974]

I'd suggest getting the CD or DVD set downloaded and use this - as I believe the mdadm raid package installation problem to only be restricted to the LiveCD. I have a bug open with Mandriva to get this looked at and fixed. Sadly, it won't be fixed for Mandriva 2008.1 Spring, but I hope it will be fixed for Mandriva 2009 release.

[johnd]

I'd suggest getting the CD or DVD set downloaded and use this

 

OK - thanks

[ianw1974]

Just to let you know, I opened a bug:

 

https://qa.mandriva.com/show_bug.cgi?id=43785

 

and it should be fixed shortly for the full release of Mandriva 2009. If they release an RC2 you could use this, but the full release definitely should have it. I will check and update on this soon when the new version is available.

[johnd]

Thanks for that - we have slow download times in NZ so I have ordered a DVD that should arrive in a day or two - should solve the problem!

[johnd]

So .. managed to figure out how to do a RAID install (doesn't seem totally intuitive to me) but got there. I have:

 

1. md0 = /boot

2. md1 = /

3. md2=swap

4. md3=/var

5. md4=/home

 

When I got to the part where the boot loader is to be installed it refused to complete the task.

 

Booted from the DVD and did a chroot and used grub-install. I got a boot loader but I am not sure what the settings are supposed to be. Not sure why this doesn't happen as part of the install process (it did with CentOS). I have done a bit of reading but there seems to be conflicting instructions so I thought I would come here before attempting anything else.

 

Thanks

John

[ianw1974]

If you were trying to use grub as the boot-loader it might not work and you might need to use lilo instead. I don't know if Mandriva fixed this or not yet.

[Guest yellowshed]

Seem to have a similar problem with trying to install to Raid0 and everything seems OK until my install fails to boot.

 

Go through from the Mandriva 2008.1 Free DVD to the partitions section. I have md0=/boot as Raid 1, md1=/ as Raid 0, md2=/var as Raid 0, and md3=/home as Raid0. I too have had the bootloader installation error, but eventually skipped it and thought I'd installed it at the summary screen (as other posts have suggested). Everything seems OK and so I reboot. During the boot up process, it gets to loading /dev/md1 and mdadm says raid0 can only find one disk - so it fails to boot.

 

If I go through the rescue gui and load the devices, it'll load /dev/md1 but fails on some of the others with UUID errors. So I manually mount them and check out the UUIDs with both mdadm --detail --scan and vol_id -u /dev/md[0-3]. They come up different???!!!!??? The fstab has the UUID reported by vol_id and the mdadm.conf has the UUID reported by mdadm --detail --scan.

 

Have tried the 2008.1 Live CD and came up against the issue of mdadm package not being installed, yet I could use it from the command line. So I manually created the raid arrays and then the partitioner recognises them and does the install. However, the net result is still the same - boots but stalls at trying to mount the /dev/md1 array (from memory, sorry. Can dig out more details tonight when I'm in front of the machine.

 

Any help, tips, pointers gratefully received.

Trevor

[ianw1974]

This only got fixed in Mandriva 2009.0 so you'll have to use Mandriva 2009.0 RC2 which is a beta/test version or wait for it's final release. It hasn't been fixed in 2008.1 and they aren't going to it seems. I opened a bug to address it.

[adamw]

There were some RAID-related bugs fixed with post-release updates for 2008 Spring, as I recall. Perhaps you could try doing a network install? That way, the install will use the latest updated packages, not the original release ones.

[Guest yellowshed]

Thanks for the quick response.

 

I don't mind getting my hands dirty with command line fixes, if it can be fixed. I assume it can as I think I had 2008.0 running like this (maybe it was 2007.1). Is it an issue in fstab - should I go away from UUID numbers? I could re-write fstab with /dev/sd[bc] whatevers if that'll still work? I assume that mdadm needs the UUID numbers. Any idea why they are different from vol_id? As an aside, I'm pretty sure I had this working when everything was Raid 1 - maybe I'll just live with that and have the security of Raid 1! :) !

 

Haven't tried the full raid install with 2009 RC2 but the default things that weren't working (intel HDA sound wasn't even listed on an install on another disk in this machine). Not sure about PulseAudio, either. Further, I need to replicate a setup for a friend to try and address an issue he has.

[ianw1974]

You could do, but it involves a lot of steps that I can't really document without knowing partitioning information, what disk was part of what array, etc, etc, etc. However, it would be something like.

 

1. Boot system from LiveCD.

2. Create /etc/mdadm.conf with all the relevant info for the arrays.

3. Run mdadm --assemble --scan to get it to activate the arrays.

4. Set up the grub stuff to install the boot loader.

 

It would be loosely based on this article I wrote for converting all your partitions from a standard disk partitions into array partitions:

 

http://www.linuxsolutions.org/index.php?op...5&Itemid=26

 

Reading from Boot Configuration onwards gives a rough idea about it - but again, I can't tell you exactly for your machine. And even then, I don't know if it will work or not for 2008.1 as I've not tried it. Initrd will probably need to be regenerated if you get kernel panics when you try and reboot. That's also documented in the link. However, if I remember right, I did this all on Mandriva 2006.0 or 2007.0.