UdevMdadm
|
Size: 1238
Comment: spec template
|
Size: 1970
Comment: implementation turns out not to exist atm
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 15: | Line 15: |
| mdadm is used by system administrators to... In order to support event-based mounting of these filesystems, we need reliable events from the block subsystem and no race conditions. | mdadm is used by system administrators to perform RAID operations such as mirroring or striping without hardware support. In order to support event-based mounting of these filesystems, we need reliable events from the block subsystem and no race conditions. |
| Line 18: | Line 18: |
* Jerry is a system administrator who uses software raid, via mdadm, for his root filesystem. He would like this to continue to be supported. |
|
| Line 25: | Line 27: |
| Most of the work for this to be supported has been done in Debian, ensuring that mdadm is run on udev events for the md block devices. A bug in edgy that exposed the UUID of the component blocks of the RAID collection has been already fixed for feisty. The UUID of the RAID itself can be exposed, as we receive udev events for when the md device is created or changed. |
|
| Line 27: | Line 35: |
| === Code === | * Merge mdadm from Debian. |
| Line 29: | Line 37: |
| === Data preservation and migration === | * Upload udev 103. |
| Line 31: | Line 39: |
| == Unresolved issues == | == Implementation update == |
| Line 33: | Line 41: |
| == BoF agenda and discussion == | The above comments turn out not to be true any more; the udev mdadm support in Debian appears to have been reverted. (-iwj 6.2.2007) random notes: mdadm -A |
Please check the status of this specification in Launchpad before editing it. If it is Approved, contact the Assignee or another knowledgeable person before making changes.
Launchpad entry: [https://features.launchpad.net/distros/ubuntu/+spec/udev-mdadm udev-mdadm]
Packages affected: udev, mdadm
Summary
This specification details how to make udev and mdadm play nicely together, in particular ensuring that udev events are issued for mdadm volumes and that UUIDs are correctly exported and do not conflict.
Rationale
mdadm is used by system administrators to perform RAID operations such as mirroring or striping without hardware support. In order to support event-based mounting of these filesystems, we need reliable events from the block subsystem and no race conditions.
Use cases
- Jerry is a system administrator who uses software raid, via mdadm, for his root filesystem. He would like this to continue to be supported.
Scope
The scope of this specification is limited to the interaction between udev and mdadm; other specifications address similar concerns with device-mapper, LVM, etc.
Design
Most of the work for this to be supported has been done in Debian, ensuring that mdadm is run on udev events for the md block devices.
A bug in edgy that exposed the UUID of the component blocks of the RAID collection has been already fixed for feisty.
The UUID of the RAID itself can be exposed, as we receive udev events for when the md device is created or changed.
Implementation
- Merge mdadm from Debian.
- Upload udev 103.
Implementation update
The above comments turn out not to be true any more; the udev mdadm support in Debian appears to have been reverted. (-iwj 6.2.2007)
random notes:
mdadm -A
UdevMdadm (last edited 2008-08-06 16:21:42 by localhost)