What’s a good mailbox size?
Written by Casper Manes on September 14, 2011
Consider this scenario. A group of IT team members are trying to design their new email system. They have an existing system in place, but it comes up a little short in meeting the demands of the user population, and is running a version of their email package that has reached (or exceeded) its end of life. Rather than just dropping a new version of the same old same in place and calling it a day, these email admins want to take the opportunity to do things better this time around. Redundancy will be included, security will be baked into the project from the beginning rather than as an add-on to the end, and sizing and capacity planning will be taken into account looking three to five years ahead.
It sounds almost too good to be true, but this exact scenario is playing out daily with my customers, and I bet many of you see a lot you are also familiar with. With Exchange 2010 SP1 now several months old, and Exchange 2003 ready for the pasture, a lot of email systems are being rebuilt right now.
A common question that comes up in planning sessions, architectural meetings, and particularly when the quote for the new SAN comes in is: “how big do we need to make users’ mailboxes?”
Email use continues to grow, and despite our wishes for the contrary, it is the de facto file sharing and transfer mechanism, which means big mailboxes are not only expected but, in many cases, they are required. There is no right or single answer, because it frequently depends on one or more factors unique to the particular company. Some of those questions could include:
-How many users must you support?
-How much email will each user, on average, send and receive?
-How many attachments will be included with email, and how large will they be?
-How far back must users be able to check for older messages?
-Is there a reason to enforce deletion of messages older than X?
-Will you implement archiving?
and many others.
As a consultant, many times I find that my clients won’t have all of those answers so they will ask “well what do you do?” or “what’s industry standard today?”
My answer to the first is easy – 25GB per user. Since many customers don’t have the storage to support that, in today’s post I am going to ask for your help answering that second question. There are other surveys out there that touch on points like this, but I want you to participate in a very short and simple survey that targets a group of your peers -email admins that read this blog.
Below is a link to the survey. All answers will be anonymous, and I will share the results with you all in a follow up post on this blog in a few weeks. We can all benefit from the answers as we design our next systems, price out that next SAN, or consider a cloud solution. Watch this space for the results. I’ll keep the survey open through the middle of October. Thanks for your participation. If you have any comments, suggestions, or anything else about the survey, please leave a comment below:
http://www.surveymonkey.com/s/ZRN2VCY
The survey is now closed. Results will published shortly.
September 14th, 2011 at 10:28 pm
The thing that I always ask my people to look at are the attachments. I ask them to do their best to keep track of every attachment that comes their way, logging quantity and file size for a week. Obviously you don’t want to have to go through their inboxes every week, so I check to make sure if we can support mailbox sizes large enough to accomodate them for at least a month without having to clean up or archive.
September 15th, 2011 at 3:38 pm
This is a classic “how long is a piece of string?” question. The questions that you list are excellent, but as you say not every business will have those answers.
I think 25GB is a bit much for a medium sized company, I would suggest 15GB for a normal user and 25GB for a special user. But as you say, that depends if the business will implement archiving.
September 16th, 2011 at 7:00 am
At present, storage size is not an issue anymore – not like 10 years ago where users have a very limited mailbox size. Hint: Gmail at first offered only 1GB of mailbox size (when it was publicly launched on April 1, 2004). Today, it’s more than 7.6GB and counting.
For me, a good mailbox size (in a corporate environment) is somewhere between 20 to 50GB. For SMEs, it should be between 10 to 30GB.
September 18th, 2011 at 11:10 pm
A 25GB email storage size (per user) sounds enough but in reality it’s not. Take for instance someone who works in sales in a big company. This worker will receive at least 50 email messages a day – with approximately 80 percent considered as spam / unsolicited emails and 10 percent for personal use (such as emails containing non-work related messages coming from friends and family).
Only 10 percent of these emails will have something to do with his or her work.
50 email messages a day is equivalent to 1,500 a month and 18,000 in a year. In my estimate (with my own experience as a heavy email user put into consideration), email storage should be between 30GB to 40GB.
September 19th, 2011 at 4:53 pm
Good idea, thanks for sharing Jon!
September 29th, 2011 at 2:47 pm
25GB is decent for the average user. For users who send/receive huge attachments because their jobs require it, I would double it, if resources permit. Storage is really cheap now, so let’s be more generous.