Should you Backup Your On-Premises Exchange – Yes or No?

By Theresa Miller • June 11, 2019

Understanding the value of why enterprises need to make sure their backups are in place has been a subject we have addressed many times here. We have covered major disasters gone right and wrong, ransomware, and Exchange online. Today we are going to dive into Microsoft Exchange on-premises, which can be an interesting topic. When designed and deployed correctly, some may argue that backups aren’t needed at all.

Let’s take a look!

Exchange Architecture

Microsoft has really done a great job throughout its many versions of Exchange to improve resiliency in the product. The ability to run multiple copies of your databases and a lagged copy of the data, plus the ability to change the deleted item retention for your mailboxes to whatever you need to recover individual messages, leaves many organizations with a tough question to answer: Do I still need to back up my on-premises Exchange databases and mailboxes? Many organizations choose not to back up their on-premises Exchange environments. With that being said, most still do, and here’s why.

As an administrator of Exchange on-premises for many years, and after seeing the unforeseeable, I’ve learned that no matter how much resiliency I can build into my Exchange environment, you will still find me backing up Microsoft Exchange. Here are two real world examples that I experienced:

  1. Unforeseen outages: When I architect an Exchange deployment, I always make sure there are 3 spinning copies of my user data. If budget and logistics allow, the 3rd copy is in an offsite datacenter. In one storage issue I was faced with, I lost most of my primary database copies and in the case of one of my Exchange databases, the only live copy left was in my disaster recovery site. The disaster was because there was a batch of bad drives in the enterprise and 100s failed within a couple-hour period of time. It may seem that the odds against that happening were quite high, but the reality is that it did happen. If we hadn’t had the disaster recovery site, I would have had to go to my database backups to restore a full database of user mailboxes.
  2. Deleted Item Recovery: Have you received a call from that VIP user where they cannot locate that very important email that they were certain they still had? If yes, then as the administrator it is likely there was some time spent looking through the deleted item retention area of Outlook for that user. In most cases that important email can be found, but I have been in countless situations where it couldn’t. In these cases, the only way to get the missing information back was to recover from backup.

The way I look at having backups for Exchange On-premises is that some of the decision will come from the corporate culture you work in, and essentially the company’s tolerance for failure.

Lessons Learned:

  • Know your enterprise requirements – Applications can have great resiliency, but at the end of the day, the decisions you make around data recovery will be determined by your enterprise requirements and tolerance for data loss.
  • Perform routine backups – especially backups that are up to date and current – will ensure that important business data can be recovered when needed.
  • Architecture – Exchange on-premises architecture when done correctly can be very robust, but be prepared for the unexpected.

Concluding Thoughts

Most organizations will want their data back no matter what. In both of the unexpected situations described above, the data needed to be able to be recovered no matter what, and I was glad I had the backups to ensure that the data could be recovered.