Bug 510707

Summary:	multipath manual for RHEL5 has no information on online resizing of a LUN
Product:	[Retired] Red Hat Cluster Suite	Reporter:	Gerard de Vos <int-leaseplan-bank>
Component:	rh-cs-en	Assignee:	Steven J. Levine <slevine>
Status:	CLOSED NOTABUG	QA Contact:	Content Services Development <ecs-dev-list>
Severity:	medium	Docs Contact:
Priority:	low
Version:	4	CC:	bmarzins, cluster-maint, edamato, int-leaseplan-bank, pkennedy
Target Milestone:	---	Keywords:	Documentation
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2009-09-03 16:47:16 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 Gerard de Vos 2009-07-10 11:18:58 UTC

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.11) Gecko/2009060215 Firefox/3.0.11

In the RHEL4 multipath manual there is an entry on how to resize a LUN while it is in use. This section was deleted for the RHEL5 version of the manual. Rightfully so because the RHEL4 instructions won't work on kernel 2.6.18/RHEL5. It is possible to resize a LUN while using it though, I wrote down how under "additional information".

Manual identifier:
Bugzilla component: Documentation-cluster
Book identifier: DM_Multipath(EN)-5 (2009-01-06T15:35)


Reproducible: Always




 Use the following procedure to resize an online multipath device.

   1. Resize your physical device.
   2. Find the paths to the LUN:
# multipath -l
   3. Resize your paths. For SCSI devices, writing a 1 to the rescan file for the device causes the SCSI driver to rescan. You can use the following command:
# echo 1 > /sys/block/<device_name>/device/rescan 
   4. Resize your multipath device by running the multipathd resize command:
#  multipathd -k'resize map mpath0'
   5. Resize the filesystem (assuming no LVM or DOS partitions are used)
# resize2fs /dev/mapper/mpath0

Comment 1 Paul Kennedy 2009-07-10 13:50:53 UTC

Reassigned to primary writer, slevine.

Comment 2 Steven J. Levine 2009-08-10 21:26:38 UTC

I sent the following note to Ben Marzinski on July 15, since he's my main technical contact and reviewer here. As soon as I hear back from Ben on this I'll get it into the next revision of the document.

-Steven


Ben:

Could you look at Bug 510707 and verify whether the information there is correct -- and thus whether I should add this procedure to the Multipath document for RHEL 5.4?

Thanks.

-Steven

Comment 3 Ben Marzinski 2009-08-12 20:05:44 UTC

Yes, this should work just fine. You can add it to the Multipath document.

Comment 4 Steven J. Levine 2009-08-14 15:13:46 UTC

I have added this procedure to the 5.4 draft and it will be in the RHEL 5.4 version when it is released.

Comment 5 Gerard de Vos 2009-08-17 11:24:55 UTC

I noticed that on http://www.redhat.com/docs/manuals/enterprise/ there was a document added: "Online Storage Reconfiguration Guide" dated July 15.
This doc does contain the resizing info. Maybe what would be handy is a link in the multipath manual that points to the new doc? Or consolidate the 2 docs?

Cheers,
Gérard

Comment 6 Steven J. Levine 2009-08-17 14:52:35 UTC

(In reply to comment #5)
> I noticed that on http://www.redhat.com/docs/manuals/enterprise/ there was a
> document added: "Online Storage Reconfiguration Guide" dated July 15.
> This doc does contain the resizing info. Maybe what would be handy is a link in
> the multipath manual that points to the new doc? Or consolidate the 2 docs?
> 
> Cheers,
> Gérard  

Gérard,

Thanks for pointing this out. I think I'll leave the procedure supplied here in the multipath manual and add a "for further information" reference to the online storage doc. I'm not sure I can make this an actual link, but I certainly can refer to the document in the manual which should point users to the document.

-Steven

Comment 7 Steven J. Levine 2009-09-03 16:47:16 UTC

With the release of RHEL 5.4, I am closing this bug.