Bug 57261

Summary:	expand md limit beyond 12 drives
Product:	[Retired] Red Hat Linux	Reporter:	Jim Wright <jwright>
Component:	kernel	Assignee:	Doug Ledford <dledford>
Status:	CLOSED RAWHIDE	QA Contact:	Brock Organ <borgan>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	7.2	Keywords:	FutureFeature
Target Milestone:	---
Target Release:	---
Hardware:	i386
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Enhancement
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2003-02-19 16:49:28 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 Jim Wright 2001-12-07 23:38:54 UTC

Description of problem:
the current implementation of the multiple devices subsystem
limits md devices to 12 drives, including spares.  the man page
for raidtab indicates that a patch to extend this to 256 drives
exists.  please consider applying this patch to future kernels.

Comment 1 Arjan van de Ven 2001-12-13 08:53:27 UTC

"12" is a bogus limit indeed; the real limit is 27 and we're evaluating if a fix
for that is enough to warrant a raidtools erratum. Above 27 is not possible
without changing the on-disk format and as a result is rather more invasive....

Comment 2 Jim Wright 2001-12-13 20:48:29 UTC

27 would be helpful for us, especially if it is easy to do.

Sounds like going past 27 is something for 8.0.

Comment 3 Jim Wright 2002-10-26 05:31:00 UTC

I haven't tried lately, but is this better in recent kernels?

Comment 4 Arjan van de Ven 2002-10-31 17:38:04 UTC

current limit still is 27 ;(
there is a on-disk layout change required for going above that, and THAT needs
upstream buy-in and such

Comment 5 Jim Wright 2002-10-31 21:08:39 UTC

sorry for not being clear.  I haven't tested lately if the limit of 12 has been
removed so the 27 limit can be reached.  I agree that exceeding the 27 limit is
an upstream issue and not an easy question.

Comment 6 Bill Nottingham 2003-02-19 16:49:28 UTC

> 12 should work in current kernels.