Bug 171862
Summary: | can't create degraded raid 4 | ||
---|---|---|---|
Product: | [Fedora] Fedora | Reporter: | Alexandre Oliva <oliva> |
Component: | mdadm | Assignee: | Doug Ledford <dledford> |
Status: | CLOSED ERRATA | QA Contact: | |
Severity: | medium | Docs Contact: | |
Priority: | medium | ||
Version: | rawhide | ||
Target Milestone: | --- | ||
Target Release: | --- | ||
Hardware: | All | ||
OS: | Linux | ||
Whiteboard: | |||
Fixed In Version: | 2.6.2-4.fc7 | Doc Type: | Bug Fix |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | 2007-07-20 19:35:31 UTC | Type: | --- |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: |
Description
Alexandre Oliva
2005-10-27 06:17:57 UTC
*** Bug 171855 has been marked as a duplicate of this bug. *** The behavior you speak of with raid5 is because mdadm does a little performance enhancement. It automatically creates raid5 arrays as being degraded and adds the final disk as a spare because reconstruction is faster than parity generation. In order to do this, it tells the kernel to assume the newly created array is clean, but degraded, then adds the spare disk. If it didn't do this, then raid5 would give the same I/O error because when you start the array as a degraded/dirty array, there is not enough disks to do reconstruction and you get the I/O error. If you pass the flag assume-clean on a raid4 create command, it mimics the raid5 behavior of telling the kernel that it is a degraded/clean array and successfully starts the array. So, the assume-clean flag is a workaround for existing setups, and for the sake of consistency, I went ahead and modified mdadm to treat raid4 like raid5 (since they actually are the same, just a different parity layout) and it now automatically creates raid4 arrays as degraded and rebuilds them. If you have a missing disk, you no longer need to pass in the assume-clean flag to get it to assemble. This will show up in mdadm-2.6.2-2 or later. mdadm-2.6.2-2.fc7 has been pushed to the Fedora 7 testing repository. If problems still persist, please make note of it in this bug report. mdadm-2.6.2-3.fc7 has been pushed to the Fedora 7 testing repository. If problems still persist, please make note of it in this bug report. mdadm-2.6.2-4.fc7 has been pushed to the Fedora 7 testing repository. If problems still persist, please make note of it in this bug report. mdadm-2.6.2-4.fc7 has been pushed to the Fedora 7 stable repository. If problems still persist, please make note of it in this bug report. |