FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Redhat > Device-mapper Development

 
 
LinkBack Thread Tools
 
Old 06-12-2008, 04:51 AM
Kevin M Lange
 
Default multipath-tools support for SGI TP9700...

Salut,



Our organization is currently
prototyping a database host which is running RHEL5 with SGI InfiniteStorage
TP9700 Storage System. *Red Hat support has effectively told us that
the device-mapper-multipath software does not support our TP9700 storage.
*Does the multipath-tools v0.4.8 support SGI TP9700? *We are
interested in contributing our hardware configuration for test of multipath-tools,
but are unable to contribute programming resources at this time.



- Kevin





Kevin M Lange

Principal Information Systems Technologist, NASA EMD Program

EMD UNIX IT Support

Raytheon Information Solutions



301.851.8450 office

301.928.2492 cell

klange@raytheon.com

5700 Rivertech Court

Riverdale, MD 20737-1250--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel
 
Old 06-12-2008, 09:48 PM
Christophe Varoqui
 
Default multipath-tools support for SGI TP9700...

Le jeudi 12 juin 2008 à 00:51 -0400, Kevin M Lange a écrit :
>
> Salut,
>
> Our organization is currently prototyping a database host which is
> running RHEL5 with SGI InfiniteStorage TP9700 Storage System. Red Hat
> support has effectively told us that the device-mapper-multipath
> software does not support our TP9700 storage. Does the
> multipath-tools v0.4.8 support SGI TP9700? We are interested in
> contributing our hardware configuration for test of multipath-tools,
> but are unable to contribute programming resources at this time.
>
TP9700 seems to look like TP9500, which has configuration defaults set.
You should try and report using the TP9500 config for 9700 in
your /etc/multipath.conf:

devices {
device {
vendor "SGI"
product "TP9[457]00"
path_grouping_policy group_by_prio
path_checker rdac
checker rdac
hardware_handler "1 rdac"
prio rdac
failback immediate
no_path_retry queue
}
}

Regards,
cvaroqui

--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel
 
Old 06-26-2008, 04:49 AM
Kevin M Lange
 
Default multipath-tools support for SGI TP9700...

Christophe,

Unfortunately it does
not appear that the TP9700 is working using the multipath device settings
you provided. *



Our configuration is such
where the host (a Sun X4600 running RHEL 5.2) is connected to the TP9700
using two Fibrechannel connections:







No FC switches are used,
just simple direct HBA to SP connectivity with two HBAs and two Storage
Processors. *LUNs on the RAID are distributed to be owned by either
SPA or SPB to distribute the workload between the SPs and the fibrechannel
connections.



The TP9700 can be configured
to present the storage to a host by setting the "Storage Array Host
Type" (Linux, SGIRDAC, SGIAVT, Windows, etc). *For my tests,
I've been experimenting with Linux and SGIRDAC. *I have been unsuccessful
in determining what the storage array host type "Linux"s failover
method is, but I thought I had come across an article that said the Linux
type is basic AVT. *I could be mistaken.



Setting the TP9700 Host
Type to "Linux" , I then setup /etc/multipath.conf to mimic the
defaults for the TP9500:



* * * *device {

* * * * * *
* *vendor * * * * * * * *
*"SGI"

* * * * * *
* *product * * * * * * * *
"TP9[457]00"

* * * * * *
* *getuid_callout * * * * *"/sbin/scsi_id
-g -u -s /block/%n"

* * * * * *
* *prio_callout * * * * * *"/sbin/mpath_prio_tpc
/dev/%n"

* * * * * *
* *features * * * * * * *
*"0"

* * * * * *
* *hardware_handler * * * *"0"

* * * * * *
* *path_grouping_policy * *group_by_prio

* * * * * *
* *failback * * * * * * *
*immediate

* * * * * *
* *rr_weight * * * * * * *
uniform

* * * * * *
* *rr_min_io * * * * * * *
1000

* * * * * *
* *path_checker * * * * * *tur

* * * *}



This configuration ran
OK for a while, then began to log multipath failures, and eventually I/O
buffer errors. *All LUNs on one SP trespassed to the other SP, and
I had to manually place each trespassed LUN back to its primary path.



Changing the TP9700 host type
to SGIRDAC, then trying the configuration you provided me caused the host
to not see the ghost path. *Effectively I ended up with a single path.
*Disconnecting a FC connection resulted in the inability to see any
of the LUNs assigned to the associated SP.



I modified the multipath.conf
a little:

*
* * * device {

* * * * * *
* * vendor "SGI"

* * * * * *
* * product "TP9700"

* * * * * *
* * path_grouping_policy failover

* * * * * *
* * getuid_callout * * * * *"/sbin/scsi_id
-g -u -s /block/%n"

* * * * * *
* * features "1 queue_if_no_path"

* * * * * *
* * path_checker rdac

* * * * * *
* * prio_callout * * * * * *"/sbin/mpath_prio_tpc
/dev/%n"

* * * * * *
* * hardware_handler "1 rdac"

* * * * * *
* * prio rdac

* * * * * *
* * failback immediate

* * * * }

This worked ok, but I see lots of scsi
sense key errors:



Jun 23 12:16:42 p4dbl03 kernel: sdbk:
Current: sense key: Recovered Error

Jun 23 12:16:42 p4dbl03 kernel: *
* <<vendor>> ASC=0x95 ASCQ=0x1ASC=0x95 ASCQ=0x1

Jun 23 12:16:42 p4dbl03 kernel:



I see those error regardless of how
I configured the RAID and multipath.conf, which is worrisome.

I especially see those errors if I run
'fdisk -l'. *



Disconnecting a FC cable on one HBA
caused the associated volumes to trespass to the other SP, however, during
this process, I noticed buffer I/O errors. *Also, I noticed that the
trespassed LUNs did not failback to their original SP when the FC cable
was reconnected. *Am I to assume that RDAC or other multipath software
will not tell the storage to failback trepassed LUNs?



Your assistance is appreciated,



- Kevin







--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel
 
Old 06-26-2008, 11:20 AM
Konrad Rzeszutek
 
Default multipath-tools support for SGI TP9700...

> their original SP when the FC cable was reconnected. Am I to assume that
> RDAC or other multipath software will not tell the storage to failback
> trepassed LUNs?

It will if the priority received from the prio_callout (or in more recent
version prio) is greater for the set of the trespassed LUNs and you are using
the right prio group policy. Try having this value in the new configuration
for the RDAC setup:

path_grouping_policy group_by_prio

--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel
 

Thread Tools




All times are GMT. The time now is 05:40 AM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright ©2007 - 2008, www.linux-archive.org