server guide: warn about using ubuntu with raid or provide reliable raid config

[ceg]

Binary package hint: ubuntu-docs

As long as we do not provide a reliable raid setup,
https://wiki.ubuntu.com/ReliableRaid:

(Package mdadm has not been synced for years, and has just too many issues,
 many fixed in stable upstream versions.
 https://bugs.launchpad.net/ubuntu/+source/mdadm)

The server guide should contain a big fat warning about the state of the raid support.
https://help.ubuntu.com/9.10/serverguide/C/advanced-installation.html

[Connor Imes (ckimes)]

ceg, thank you for your report. Do you have specific suggestions on how to improve the existing documentation so that it is up to speed for Karmic and Lucid?

[ceg (ceg)]

Hi,

from what I have gathered now, two things are generally expected (as in just works on in other distros) but is missing functionality in ubuntu:

 1) No handling of raid degration during boot for non-root filesystems (at all).
      (Boot simply stops at a recovery console)

 2) Only limited and bugy handling of raid degration for the rootfs.
     (Working only for plain no lvm/crypt md's and after applying a fix from the 9.10 release notes.)

The other points on https://wiki.ubuntu.com/ReliableRaid are bugs that hold back reaching the design goals that are associated with the original move to use a hotplug (udev) setup in ubuntu.

[ceg (ceg)]

https://wiki.ubuntu.com/ReliableRaid updated. See rationale.

[Connor Imes (ckimes)]

viclyn (oobiauk), thank you for your interest in working on this bug. Are you planning on fixing this bug before the String Freeze for Lucid? String Freeze is March 25, so we need a patch before then in order to have time to review it and then commit it and upload it for Lucid. Please let us know by the end of the week, or I will need to unassign you from the bug. Thanks for understanding.

[Vikram Dhillon (dhillon-v10)]

For now providing a warning is perhaps the best idea, the package seems to have a lot of problems, and even if it might work one time its would give problems in the long term.

[Connor Imes (ckimes)]

The Ubuntu Documentation team has moved the serverguide out of the ubuntu-docs source, it is now under the serverguide project. Moving this bug accordingly.

epic, I'm unassigning you during this move since there has been no followup. If you would still like to work on this bug, we would appreciate your help and feel free to assign yourself again. Thanks.

[Dimitri John Ledkov (xnox)]

Hello 2012!
On this page of the server guide:

   https://help.ubuntu.com/12.04/serverguide/advanced-installation.html

Still does not have warning about bugs which currently make RAID unreliable on ubuntu.
Can this be mentioned? Or what needs to be done to include a symlink to an up to date state of RAID on Ubuntu.

I will be updating https://wiki.ubuntu.com/ReliableRaid soon as part of the

https://blueprints.launchpad.net/ubuntu/+spec/foundations-q-software-raid

[Peter Matulis (petermatulis)]

@Dmitrijs

a) Specifically, what bugs do you think should be mentioned?

b) What do you mean by 'symlink to an up to date state of RAID'?

[Peter Matulis (petermatulis)]

The wiki page was never updated as promised so I am marking this as 'Incomplete'.

[Launchpad Janitor (janitor)]

[Expired for Ubuntu Server Guide because there has been no activity for 60 days.]