This may be a somewhat simplified question, but I've read online quite a bit and have found very little on the comparison. We are a smaller shop, approximately 200 users. Currently our Exchange mailbox quotas are set at 400MB. For as long as I can remember we've had users archive email as they fill up their mailbox, so we have more .psts floating around than we would like. I've looked into the archiving feature of Exchange, and it looks nice, but I'm having a hard time determining why I would go that route (for the cost, would be about 12K for licensing) versus just having more hard drive space on the server and increasing everyone's mailbox limit to 10GB (for example).
I would imagine having their primary mail on one server and archive on another would be ideal for balancing the load/stress on the system, but with our small shop we only have the one server/database and had planned on putting the archive database on the same server anyway. We plan to deploy DAG with a DR site in the near future as well.
So, other than being able to give our legal department more capabilities with the discovery process, is there any benefits I'm not seeing here? Also, we are currently on Office 2007, from what I read a lot of features aren't usable unless you are running 2010, so that would be something else to take into consideration I suppose. But anyway, I would appreciate some thoughts on this from those who have used both ways and are more "in the know" than I am with regards to Exchange/archiving. :) Thanks for your input!
No, and guess what - does not have to be. The legal implications are huge. Not running a reliable mail archiving - you are immediately in violation of the law if you are in certain jurisdictions.
Emails are in some jurisdictions legal documents of your business, if you discuss stuff like contract term or do contract negotiations over them and you are legally obliged to keep copies for 10 years ;) No archive? you already lost in court - given that you violated (in that certain jurisdiction) your requirements to keep copies of your legal paperwork, you now have to prove I did not send you certain emails. Reversal of discovery process due to failure to adhere to legal requirements. OUCH.
Sarbanes Oxley, OTOH has huge implications on US stock company reporting legal requirements. US stock companies can not run free linux servers legally without some archival in front for reporting reasons (easily).
This is not "just the legal department capabilities", it is "run something that blows in court for not following the law".
The primary reason we use it (aside from the very well thought out legal points @TomTom made) is to place large Archive mailboxes on cheaper slower storage.
For example our primary mailboxes have 2GB quota on 15k FC while our Archive Mailboxes for users can run up to 100GB on FATA. Obviously the access is a bit slower, but the cost/storage ratio makes it work. Plus we don't have the issue of "Oops, computer crashed all my mail from my local archive is gone"
Mailboxes will keep growing, and growing, being able to place not often accessed messages on secondary cheap storage will cut your costs in the long run.
You can see Online Archives in Outlook 2007, but the support for polices and searches is limited.