BootDegradedRaid

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 * '''Created''': [[Date(2008-05-30)]]  * '''Created''': 2008-05-30
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 * '''Packages affected''': mdadm, grub  * '''Packages affected''': mdadm, grub, initramfs, udev, lvm2
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This specification defines a methodology for enhancing Ubuntu's boot procedures to configure and support booting a system dependent on a degraded RAID1 device.
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Ubuntu's installer currently supports installation to software RAID1 targets for /boot and /. When one of the mirrored disks fails, and mdadm marks the RAID ''degraded'', it becomes impossible to reboot the system in an unattended manner.

Booting Ubuntu with a failed device in a RAID1 will force the system into a recovery console.

In some cases, this is the desired behavior, as a local system administrator would want to backup critical data, cleanly halt the system, and replace the faulty hardware immediately.

In other cases, this behavior is highly undesired--particularly when the system administrator is remotely located and would prefer a system with redundant disks tolerate a failed device even on reboot.
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== Implementation ==

== Outstanding Issues ==

== BoF agenda and discussion ==

== References ==

 * https://blueprints.launchpad.net/ubuntu/+spec/boot-degraded-raid
 * https://wiki.ubuntu.com/UDS-Intrepid/Report/Server#head-75c995bdf63bb5afe0f08461aba9200b6c95814f
 * https://lists.ubuntu.com/archives/ubuntu-devel/2007-September/024221.html
 * http://www.outflux.net/blog/archives/2006/04/23/grub-yaird-mdadm-and-missing-drives/
 * wiki:Bug:120375
 * wiki:Bug:125471

Summary

This specification defines a methodology for enhancing Ubuntu's boot procedures to configure and support booting a system dependent on a degraded RAID1 device.

Rationale

Ubuntu's installer currently supports installation to software RAID1 targets for /boot and /. When one of the mirrored disks fails, and mdadm marks the RAID degraded, it becomes impossible to reboot the system in an unattended manner.

Booting Ubuntu with a failed device in a RAID1 will force the system into a recovery console.

In some cases, this is the desired behavior, as a local system administrator would want to backup critical data, cleanly halt the system, and replace the faulty hardware immediately.

In other cases, this behavior is highly undesired--particularly when the system administrator is remotely located and would prefer a system with redundant disks tolerate a failed device even on reboot.

Use Cases

Scope

Design

Implementation

Outstanding Issues

BoF agenda and discussion

References

BootDegradedRaid (last edited 2010-04-21 10:02:37 by 188-194-18-172-dynip)