Comments on: My first lefthand ISCSI VI architecture http://frankdenneman.nl/2009/03/my-first-lefthand-iscsi-vi-architecture/ Tue, 07 Feb 2012 07:27:32 +0000 hourly 1 http://wordpress.org/?v=3.3 By: Beto http://frankdenneman.nl/2009/03/my-first-lefthand-iscsi-vi-architecture/comment-page-1/#comment-49 Beto Fri, 04 Sep 2009 12:49:43 +0000 http://frankdenneman.wordpress.com/?p=120#comment-49 I suppose one of the easiest ways to verify this is to test it before it goes into production. Set up the various nodes of your cluster with some test LUNs, then go yank a cable or otherwise instigate a failover and see how things work. Also, I'm not sure if this applies to lefthand, but I know with other vendor storage, it has been shown that NFS-connected (NAS) datastores actually get better performance than ISCSI LUNs. This may be something else to consider if you've got cycles to burn in your testing phase, although if you're coming from an FC world this also may go against everything you know :) (see this thread as a starting point in the debate - http://communities.vmware.com/message/737269) Best of luck in your deployment! I suppose one of the easiest ways to verify this is to test it before it goes into production. Set up the various nodes of your cluster with some test LUNs, then go yank a cable or otherwise instigate a failover and see how things work.

Also, I’m not sure if this applies to lefthand, but I know with other vendor storage, it has been shown that NFS-connected (NAS) datastores actually get better performance than ISCSI LUNs. This may be something else to consider if you’ve got cycles to burn in your testing phase, although if you’re coming from an FC world this also may go against everything you know :) (see this thread as a starting point in the debate – http://communities.vmware.com/message/737269)

Best of luck in your deployment!

]]> By: Ray http://frankdenneman.nl/2009/03/my-first-lefthand-iscsi-vi-architecture/comment-page-1/#comment-48 Ray Sun, 07 Jun 2009 12:43:34 +0000 http://frankdenneman.wordpress.com/?p=120#comment-48 We've only used iscsi and a combination of Sanmelody (single and multiple paths/HA) as well as Equallogic. While everything "just worked" I saw what you mentioned and no amount of Googling helped (as you found out). I even went to the point of making sure the Send Targets were in the same order on each host, nope, still the same (well different :) Be interested to know if there is a doc on this somewhere, it's been a over a year for us now with the setup and all good! Ray We’ve only used iscsi and a combination of Sanmelody (single and multiple paths/HA) as well as Equallogic. While everything “just worked” I saw what you mentioned and no amount of Googling helped (as you found out).
I even went to the point of making sure the Send Targets were in the same order on each host, nope, still the same (well different :)

Be interested to know if there is a doc on this somewhere, it’s been a over a year for us now with the setup and all good!

Ray

]]> By: Paul Petty http://frankdenneman.nl/2009/03/my-first-lefthand-iscsi-vi-architecture/comment-page-1/#comment-47 Paul Petty Tue, 14 Apr 2009 13:04:05 +0000 http://frankdenneman.wordpress.com/?p=120#comment-47 Thats a good question and one that I'm just discovering for myself too. We have an ESX cluster connected to several HP FC EVAs at present but we also have a large (ish) Lefthand iSCSI SAN which we want to be able to provision some data volumes for VMs. When we present multiple LUNs from the iSCSI SAN on each host they appear as LUN ID 0 but with different iSCSI target IDs? Like you, coming from a fibre world this seems strange and very off putting to me. I carried on doing some testing and added 3 LUNs to each node in the cluster and then created a VMFS on the first LUN. To my surprise this new VMFS worked and appears on all of the nodes that the LUN is presented to and likewise for additional VMFS disks too. All seems well in testing so far but if there is any difinitive answer out there I'd like to hear it. Paul Thats a good question and one that I’m just discovering for myself too. We have an ESX cluster connected to several HP FC EVAs at present but we also have a large (ish) Lefthand iSCSI SAN which we want to be able to provision some data volumes for VMs. When we present multiple LUNs from the iSCSI SAN on each host they appear as LUN ID 0 but with different iSCSI target IDs? Like you, coming from a fibre world this seems strange and very off putting to me.
I carried on doing some testing and added 3 LUNs to each node in the cluster and then created a VMFS on the first LUN. To my surprise this new VMFS worked and appears on all of the nodes that the LUN is presented to and likewise for additional VMFS disks too.
All seems well in testing so far but if there is any difinitive answer out there I’d like to hear it.

Paul

]]> By: Ken Cline http://frankdenneman.nl/2009/03/my-first-lefthand-iscsi-vi-architecture/comment-page-1/#comment-46 Ken Cline Mon, 30 Mar 2009 21:17:38 +0000 http://frankdenneman.wordpress.com/?p=120#comment-46 Hey Frank, Nice article - please keep us updated on how you progress. I'm interested in the solution to your (possible) problem! KLC Hey Frank,

Nice article – please keep us updated on how you progress. I’m interested in the solution to your (possible) problem!

KLC

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