3 node SCC A/A/P cluster possible? (Full Version)

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troy12n -> 3 node SCC A/A/P cluster possible? (21.Mar.2008 2:38:04 PM)

I have been researching how to do this, or if its even possible, as EX2007 SP1 documentation out there isnt terribly tremendous yet.

What I am trying to accomplish is to have a three node SCC cluster where I have 2 mailbox servers active nodes and one passive node. I have a SAN which they can use for shared storage. All this would be at the same site.

I guess my basic question is #1: is this possible, #2, how would you do this? I know you can go in and set up mailbox servers as clustered mailbox server active or passive, but when you install the passive node, I think it asks you which mailbox server (not servers) you want it to be the passive node for (not multiple).

I am thinking there has to be a way to do this.



mark@mvps.org -> RE: 3 node SCC A/A/P cluster possible? (21.Mar.2008 2:49:38 PM)

It's possible and allowed. It's certainly no longer recommended.
I would advise against even bothering to try. Getting support is just going to illicit groans and it's going to tie you up in knots.
Microsoft's official recommendation with SCC is A/P and then another SCC for another A/P.
Actually the recommendation is CCR rather than SCC. I would urge you to think along those lines.



troy12n -> RE: 3 node SCC A/A/P cluster possible? (21.Mar.2008 2:56:44 PM)

From what I have read, doing a CCR cluster puts in some real big (for us) restrictions like no public folders (I HAVE to have public folders), no automatic failover (WTF??) of a active node.

I am being forced to use the outlook 2003 client because of change in licensing of the outlook client by M$, so I have to be able to have public folders for free/busy.

What is the aversion to the A/A/P scenario? Seems ideal to me, as it protects you against hardware failure (unless you are in a situation where you lose 2 servers at the same time, very unlikely) and saves you hardware and licensing costs.

Is there a technical reason why you dont recommend it? If so, thats fine, I would like to hear about it though.



Elan Shudnow -> RE: 3 node SCC A/A/P cluster possible? (21.Mar.2008 5:13:57 PM)

You CAN have public folders on CCR.  You can't have public folders on your CCR if you have "more than one" public folder database in the organization due to public folder replication.

If you were migrating from Exchange 2003 and have only 1 public folder database, you can create a CCR right off the bat and create the public folder database since you did not install CCR with more than 1 public folder database being in the organization.

If you do have more than 1 public folder database, all you have to do is bring up a regular mailbox server, have it create the public folder database, then bring up your CCR cluster.  You will then migrate public folder information to the mailbox server and mailboxes to the CCR cluster.  You can do this in parralel if you wish.

Once you decomission Exchange 2003, you then only have 1 public folder database in your organization.  You can then create the public folder database on your CCR cluster, migrate everything to the public folder database on your CCR cluster, then de-comission your Mailbox Server.

Only technical reason I'd advise against the A/A/P is that if both Active Nodes fail, depending on the hardware configuration of the passive node, that passive node will get sucked dry in terms of resource utilization.  This is generally why Microsoft doesn't recommend A/A.  A lot of people don't stick to their design and they keep increasing resource utilization on their Active Nodes by adding more stuff than they orginally anticipated. At the same time, people skimp on the Passive Mode to them not being able to justify spending money on a server that does nothing.  They'll just "deal" with the lack of performance.

But honestly, that can even be said for a regular A/P model.  You can still get one beefy server and skimp on the other.  So if you do go for the A/A/P, please, don't skimp on the passive box and make sure it can handle the load if both Active Nodes were to go down.



troy12n -> RE: 3 node SCC A/A/P cluster possible? (24.Mar.2008 9:41:34 AM)

Ok, here is my situation. I am actually not running Exchange right now. I am running Novell Groupwise 7, we will be migrating to Exchange in fall of 2008.

I had planned on using public folders as a substitute for Groupwise's Shared folders functionality (public folders are not as good, but at least its something). I anticipate having to have more than 1 PF DB.

As for your point about resource utilization, that is absolutely valid, but the chances of me losing more than 1 server hardware at a time are VERY slim and I am prepared to take that chance. I purchased all new hardware for these servers, each server is an HP DL380G5 with dual Quad core processors and 32 gigs of ram each. They connect up via 2 gig fiber to one of our HP EVA 8000 series SAN's using 15k rpm disks. I have plenty of this type of server laying around in case I lose one, I can swap another one in, the only thing would be my spares do not have 32 gigs of ram, so performance could be deprecated until I get hardware replacement (next business day), but assuming i only lose 1, I can have the slower server be the passive node.



Elan Shudnow -> RE: 3 node SCC A/A/P cluster possible? (24.Mar.2008 1:50:29 PM)

Since you're coming from GroupWise, my advice to you is to deploy Outlook 2007 only and to use SharePoint instead of Public Folders.  The reason for this is Outlook 2007 can take advantage of downloading things such as Offline Address Book and Free/Busy without the need for Public Folders.  Outlook 2007 can also take advantage of the Autodiscover service which does automatic profile creation as well as automatically detecting a change as I explained earlier with Move-Mailbox -configurationonly.

Microsoft is de-emphasizing public folders and will be even more de-emphaized in Exchange 14.  They are trying to push Sharepoint Portal for collabaration features that public folders previously provided.  I would check the following link to see what Sharepoint offers as a substitute for Public Folders.  But really, my recommendation is to go to Sharepoint due to the de-emphaized nature of Public Folders
http://technet.microsoft.com/en-us/magazine/cc137992.aspx



troy12n -> RE: 3 node SCC A/A/P cluster possible? (24.Mar.2008 4:47:42 PM)

I am well aware of that, however, my organization has office 2003 deployed, and since exchange licenses no longer include the outlook client as part of that, we have to deploy the outlook 2003 client. It would cost us a couple hundred thousand dollars just in licenses just to deploy outlook 2007, money we do not have. 



BarrenT -> RE: 3 node SCC A/A/P cluster possible? (27.Mar.2008 11:41:33 AM)

Hi

Apologies for a slight thread hijack here but a few of the responses have concerned me somewhat.
On Exchange 2003 we are running a 5 node (soon to be 7 node) 'SCC' configuration and it is stated here that this is no longer recommended  - I'd be really grateful if you could rpovide links to the documentation which state this as this will seriously affect our planning for Exchange 2007.

On Exchange 2003 each EVS can be assigned a preferred owner which essentially provides a priority list for passive nodes - this thread implies (apologies if I've misread) that 2007 offers a one active to one passive failover configuration so if you have multiple passive nodes they cannot be utilised by all of the active nodes you have?

Additionally some advice is given against running AAP as if both active nodes fail then the passive will become overloaded with 2 active nodes processing. Are there links for this information also please as in 2003 one node can only hold one EVS so unless you were running in A/A mode you could never be in a situation where two EVS's failed to one passive node as the second fail would never be loaded on the passive node.

Please excuse my ignorance on the 2007 side of things but if the advice above is true then these are some pretty major changes which are not held in the most obvious documentation (at least which i can find :) ) and it would be most useful to know these things before design phases for our potential 2007 upgrade.

Many Thanks



goof1427 -> RE: 3 node SCC A/A/P cluster possible? (10.Jun.2008 1:49:49 AM)

This is more of a question in response to Mark's answer... that SCC is no longer recommended. Where can I find this information? We are also planning an 3 node active 1 node passive SCC mode. If this is not recommended does that mean it is not supported? and how possible is it to setup? if at all?

And how do I find out what mode I am running whether CCR or SCC. I installed Exchange 2007 as SCC however our 3rd party vendor is saying that it is in CCR mode...how is that possible?



BarrenT -> RE: 3 node SCC A/A/P cluster possible? (10.Jun.2008 4:30:11 AM)

At a (very) simple level I would suggest that the storage is a good indicator of the mode of operation.
SCC shares the storage between all the nodes -  often using a SAN for example whereby a failure in one node causes the whole EVS and its storage to 'move' to the passive node, thereby working on the same data ; CCR has a copy of the data on each nodes storage therefore in a failure the passive nodes own 'copy' of the data is used.
At least thats how we differentiate the two :)



goof1427 -> RE: 3 node SCC A/A/P cluster possible? (10.Jun.2008 9:31:36 AM)

I understand that part... but its more like if people question whether you installed SCC or CCR in the beginning phase .... isnt in the ExchangeSetup logs as to what mode was picked?... im just trying to prove someone wrong.. :) ...they think i chose CCR while im pretty sure its SCC... so then it becomes like OfficeSpace...you have like 8 bosses or people coming and telling you what they think you did wrong.


so the failover is to a SAN...not to another node which has a copy...



hcxeadmin -> RE: 3 node SCC A/A/P cluster possible? (11.Jun.2008 1:50:33 AM)

Hi, one of the easiest way to tell what type of cluster you have is to open cluster admin.  Check your cluster group and if you see a resource called "majority node set" then you have a ccr.  If you have a quorum drive, well, there you have it.  If you do have a CCR don't forget to check to see where your file witenesses are in case someone decides to screw with it.  There are other ways to chech through the shell and console as well. 

MS will still support SCC.  They will always need to offer you other HA options that are not costly like CCR.  SCC is a completely viable option depending on your needs and budget.  We have implemted five CCR servers and two right-arms (we have another 10 server in diff roles as well).  We also are migrating from a 2003 seven node cluster.  I do pref the CCR but would totally understand why someone would chose SCC.




neilho -> RE: 3 node SCC A/A/P cluster possible? (13.Jun.2008 3:37:23 AM)

Use the Exchange Management Shell of course.

Run the Get-MailboxServer cmdlet and check the 'ClusteredStorageType' property.




neilho -> RE: 3 node SCC A/A/P cluster possible? (13.Jun.2008 3:44:40 AM)

quote:

ORIGINAL: Elan Shudnow

You can't have public folders on your CCR if you have "more than one" public folder database in the organization due to public folder replication.



This is not strictly true.  You CAN have public folders on your CCR environment even when coexisting with E2K3.  Technically it's fine.  The only time there will be an issue is if you have a lossy failover on the CCR environment during the coexistence.  Otherwise things will be fine.  If you understand this risk and are willing to accept it, then replicate/re-home PFs as quickly as possible and decomission E2K3 thereby leaving just the one PF database.



goof1427 -> RE: 3 node SCC A/A/P cluster possible? (13.Jun.2008 9:45:59 AM)

It says nonshared... also on a CCR installation there is a tab for CCR when you go to the properties of a storage group. just found that out. :)

should it be nonshared? if its on a SAN ...shouldnt it be shared?



neilho -> RE: 3 node SCC A/A/P cluster possible? (13.Jun.2008 12:00:11 PM)

Non-shared is the term for CCR in this context, so that's what you have.

As for the SAN, the link to "shared" is irrelevant here since you can have CCR implemented on a SAN - you'd obviously have two copies of the databases on the same SAN though (unless, of course, you've implemented another SAN or perhaps you've got one set of databases on a SAN and another on DAS).

Either way, you've got CCR.  [;)]



goof1427 -> RE: 3 node SCC A/A/P cluster possible? (13.Jun.2008 12:14:47 PM)

how is that possible when i chose scc during the installation. and theres no CCR tab on the storage groups. so the question becomes how do i change it to SCC?



zachy111 -> RE: 3 node SCC A/A/P cluster possible? (2.Jul.2008 4:42:01 PM)

I have implemented a SCC, A/A/P cluster, ISCSI SAN (EQ) (SATA), 2200 users low to med Exchange user profile (IO). SCR copies to DR site.

Running perfectly with no issues. I have not seen any recommendation from MS not to do this. If I was more compfortable with CCR I might have gone that route. But, we had the hardware so why not SCC.



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