Introduction
I regularly meet with customers and discuss their Exchange Server architecture. Two topics frequently come up so I thought I'd discuss them with everybody and give my perspe...
Updated Jul 01, 2019
Version 2.0
Blog Post
First I don’t think comparing an Internet Service Provider users to corporate users is a valid approach. The usage scenario is completely different. Did you know that they do not guarantee restore times or SLA's around data availability or recoverability? Also, we typically see that once a limit is established, end users typically utilize 45-60% of that limit, but of course you will always see a bell curve with maibox sizes.
As for your sizing recommendation, well I will disagree with you there. If you base things on averages and not the maximum that can possibly occur (it’s very easy to perform a DoS based attack and flood the environment with messages – I have one customer that routinely sees this within their environment because they won’t lock down distribution groups, and they get into a bedlam or “reply all” battle) then you will find at some point you will have to extend your storage. Let me give you an example, within Microsoft, we designed our storage to support 4000 200MB mailboxes (with a database overhead factor of 1.4) per Exchange server spread across 20 databases. At any point in time we can say that our database size will never exceed 55GB because we have limits in place and we know what the maximum will be. If we designed without those limits, we would not be able to achieve our RTO and RPOs for backup and restore. Also, this configuration has been in place for almost 4 years with zero storage changes. I have yet to meet a customer that has had zero limits and not had to extend their capacity as a result. But I have met many that have implemented them and have stories like Microsoft IT's.
Yes I do agree with you regarding teh storage facility comment, and I should have expanded on what I meant as I was really referring to internal communications. SharePoint and other technologies are viable for intranet and established business partner communications. They aren’t viable for Internet usage, so yes email is usually the best method for transferring data. By the way, the SharePoint technologies do offer automatic site deletion capability.
Ross
As for your sizing recommendation, well I will disagree with you there. If you base things on averages and not the maximum that can possibly occur (it’s very easy to perform a DoS based attack and flood the environment with messages – I have one customer that routinely sees this within their environment because they won’t lock down distribution groups, and they get into a bedlam or “reply all” battle) then you will find at some point you will have to extend your storage. Let me give you an example, within Microsoft, we designed our storage to support 4000 200MB mailboxes (with a database overhead factor of 1.4) per Exchange server spread across 20 databases. At any point in time we can say that our database size will never exceed 55GB because we have limits in place and we know what the maximum will be. If we designed without those limits, we would not be able to achieve our RTO and RPOs for backup and restore. Also, this configuration has been in place for almost 4 years with zero storage changes. I have yet to meet a customer that has had zero limits and not had to extend their capacity as a result. But I have met many that have implemented them and have stories like Microsoft IT's.
Yes I do agree with you regarding teh storage facility comment, and I should have expanded on what I meant as I was really referring to internal communications. SharePoint and other technologies are viable for intranet and established business partner communications. They aren’t viable for Internet usage, so yes email is usually the best method for transferring data. By the way, the SharePoint technologies do offer automatic site deletion capability.
Ross