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Community Member

Unity upgrade, DiRT or COBRAS

Hi all

Was wondering what you guys think.

My scenario is: Unity 4.0(5) UM with Exchange 2003. 2000 Users. Want to upgrade to Unity 5 while

Upgrading Hardware to. I want to also then point Unity 5 to the new Exchange 2007 cluster already

running on the Domain.

So this is the 2 options I think I have.

1) RunSchema updates for Unity 5

Upgrade current 4.X Server to 5.x

DiRT Backup Unity

Build new hardware into Domain and install Unity 5 (new name and IP)

Switch off old server and DiRT restore on new one.

Point new server to Exchange 2007 cluster.

2) Install Unity 5 on new Hardware with new name and IP

Point it to Exchange 2007 cluster.

Use COBRAS to export Subscribers of Unity 4 server

Import them on Unity 5 server.

Switch of old Unity 4 server

Cisco Employee

Re: Unity upgrade, DiRT or COBRAS

Both COBRAS and DiRT use the same directory synch logic (i.e. they both ask the Unity DirSync process to fire up) - so this assumes all the accounts are already created in Ex2007 I assume (Unity cannot create new 2007 accounts on the fly yet - MS yanked the interface to allow that for "security reasons" - they're working on it).

Short version is DiRT will get you more data since it's a table based backup/restore and COBRAS will save you some time by avoiding the upgrade.

Normally for a move like this I recommend DiRT - it's been out there much longer and is designed for full system moves like this.

Community Member

Re: Unity upgrade, DiRT or COBRAS

I will wait for all the users to be migrated to Exchange 2007 before doing the upgrade.

I have used DiRT before on this server to get it from an earlier version of 4 to 4.0(5). While I was doing this I changed to bigger HDD's.

I think COBRAS will give me the least amount of downtime.

This server has over 2000 subscribers.

Community Member

Re: Unity upgrade, DiRT or COBRAS

I had almost the same scenario, except for new hardware. I had the upgrade fail multiple times using DiRT, and TAC did not offer an explanation. I had to restore to the original version at the end of each attempt. In the end COBRAS saved the day.

Cisco Employee

Re: Unity upgrade, DiRT or COBRAS

I'd definitely get backups using both to be safe - no reason not to.

With COBRAS, however, be careful that when you do the restore of the users onto your new box if the directory is shared the dir synch will cause errors to kick out on the old box (i.e. the shared AD objects will get "Restamped" to point at the new box which the old Unity server will not appreciate). If the plan is to take the old server off line before importing users into the new box then this wont be a problem - just thought I'd note it since a few sites have tried to use COBRAS as a load balancing tool to "move" users around multiple Unity servers in a site - and that's not what it does.

Community Member

Re: Unity upgrade, DiRT or COBRAS

I think I will go with DiRT.

Now my worry is Exchange 2007.

Currently, the users are on 2003 and not migrated to 2007 yet.

What are my options here to eventually have upgraded to Unity 5 with new hardware and partner with Exchange 2007

I'm thinking :

Schema changes, upgrade the current Unity to 5, do a DiRT backup while users still on Exchange 2003, switch it off and remove it from AD.

Install new hardware and install Unity 5 on it, partner this server with Exchange 2007, and DiRT restore.

Can DiRT do this ?


Cisco Employee

Re: Unity upgrade, DiRT or COBRAS

Unity's directory monitor cannot create mailboxes on Exchange 2007 from scratch, it can only import existing user/mailboxes currently. DiRT uses the Unity directory monitor to do it's business (as does COBRAS) - so you will need to make sure all your users are already created and have mailboxes before you do the DiRT restore with Ex2007 - the synch process will find the existing users with mailboxes in the directory and bind to them. If they don't exist then the synch for that user will fail.

Community Member

Re: Unity upgrade, DiRT or COBRAS


Is dirt restoring to a Exchange 2007 based Unity deployment now TAC supported? still says in red letters that this is not supported.

I am not planning to use DIRT or exmerge to move messages during this DIRT restore, I just need DIRT to restore the Unity DB to the new Unity server and to sync with AD and stamp/repoint the users to the new Unity server.

Cisco Employee

Re: Unity upgrade, DiRT or COBRAS

This was pending some documentation coming out of the tech pubs group for how to go about such restores properly - I'll ping the Unity team again and see where it's at.

Cisco Employee

Re: Unity upgrade, DiRT or COBRAS

Short version is QA finished their testing but there's 2 big issues here.

1. You can't create new users on the DiRT restore - that's been discussed out here. The engineering folks hoped to find a way around MS's lock down on that but nothing supportable was found. So the users must exist in AD already.

2. MS pulled support for ExMerge in 2007 and offers no alternative. I've seen hacks that can make it work but these are not things we can encourage or support so message restore with DiRT on 2007 is not going to be supportable.

They've asked me to update the help with this info and to warn users when you run DiRT restore on a box hooked to Ex2007 of these issues. There wont be any binary changes to DiRT itself so if the above limitations are ok with you, you can proceed with the latest version off its home page. Be sure to check the logs for failed syncs with the directory when users in AD can't be found - it can result in some of your users being yanked from the database post restore which is a bit confusing.

Community Member

Re: Unity upgrade, DiRT or COBRAS

Great. Thanks, this makes sense.

One more question going back to the original post about dirt v cobras.

Regarding the first issue, I understand from Ciscounitytools that Cobras also faces the same limitation regarding creating new users during an import. So I am ok with this part.

However, since Cobras uses MAL to export/import the messages, is it supported to import messages using Cobras to a Unity deployment with subscriber mailboxes on Exchange 2007?

Cisco Employee

Re: Unity upgrade, DiRT or COBRAS

Yes, the message import from COBRAS should work against 2007 - keep in mind it only gets non secure voice mail (no fax, email, receipts etc...) - but for just voice mail it should work.

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