The level of difficulty may vary depending on your installation size, database/index sizes, etc.  There were definite changes between 7.2 and 7.3 you should be aware of before you take on the upgrade.  This includes the introduction of the java/web-based NetWorker Management Console (NMC) as the default user interface for backup operations.  There are also changes to the media database and the index directory structure where a conversion takes place when you upgrade. 

The thing to consider with a multi-version jump is that there have been a number of changes between versions and so it simply requires some care and planning.  This should including taking a look at whether the hardware you've had running your 7.2 environment is going to be sufficient to support 7.6.

Probably the best set of resource for you to review are a set of docs that outlined upgrades from earlier versions.  These are available here (the following links are on Powerlink and if for any reason you don't have access, let me know and we'll get them to you).

https://support.emc.com/products/NetWorker/InstallationAndUpgrade.aspx

http://powerlink.emc.com/km/live1/en_US/Offering_Technical/Technical_Documentation/300-007-011.pdf <=probably this is the best baseline setter for you for 7.2 to higher versions.  The increments from here were smaller.

http://powerlink.emc.com/km/live1/en_US/Offering_Technical/Technical_Documentation/300-010-410.pdf <=this gives you NW 7.5 changes

http://powerlink.emc.com/km/live1/en_US/Offering_Technical/Technical_Documentation/300-008-997.pdf

I know Allan asked in the other Fast Start thread about details of your environmment - so if you have any details to share on that, there may be additional comment/suggestions that can be made.

Regards,

Eric

Thanks Eric, we are currently running a basic setup with about 10 - 12 clients, 1 exchange, and about 4 sql.  most of all of these are running the old client release - 7.2.  Will I be required to upgrade all of my clients and modules with an upgrade to 7.6?

We also have 2 powervault tape drives that we use.

Given what you've indicated, I think your upgrade should be fairly easy.  You do not have to upgrade all your clients at the same time as the server.  The only exception would be if you had a client that is also a storage node.  Storage nodes must be upgraded at the same time as the server for the upgrade from 7.2 to a later version.  The only issue w/ not upgrading the clients within some foreseeable timeframe would be the support issue (that the software is EOL'd).  As far as ability to backup though, you're fine.

I thought of another resource you might want to check out.  It's the NW procedure generator tool (also on Powerlink).