I can give you my 2 cents. We migrated a few thousand users a couple of years ago.
1. You will probably need more internet bandwidth. This will really depend on a few things, how heavily used is your internet connection currently, number of users, and how many file attachments users are going to be opening daily (and of course the bigger the size limit the more bandwidth they will consume) 2. Be prepared for some users to not work, and others to work. Since your mailboxes get spread out across servers it is possible for 1 or more users to have issues while other work fine. This was always annoying as the outages at MS always seemed to find my C-Level execs mailboxes, very rarely just a regular end user 3. Backups in general. I had several issues were a users mailbox became corrupt and after several days of dealing with premier support the determination was made the mailbox and it lagged copies were corrupt and the only option was to delete the mailbox and recreate it (not an option when it is an execs mailbox). So make sure you have someway to back up your mailboxes. 4. I have been away from the day to day management of o365 for a little under a year, but Regular support when I left was HORRIBLE. And while Premier support was not much better, it is something to keep in mind when making the decision. 5. While #1 will have some to do with this, your users need to remember their mailboxes are in the cloud. As a result, that nice speedy 100/Full, or GiG/Full connection they had to your local network which allowed them to open file attachments quickly, has been reduced significantly by the your internet connection and distance to o365. So file attachment that would take 1 or 2 seconds to open, probably now result in outlook displaying the good old, outlook not responding as it opens/saves the attachment. From: listsad...@lists.myitforum.com [mailto:listsad...@lists.myitforum.com] On Behalf Of Damien Solodow Sent: Monday, February 15, 2016 9:46 PM To: excha...@lists.myitforum.com Subject: [Exchange] Upgrade on-prem vs Office 365 Our on-prem setup is Exchange 2010 SP3, so we're going to want to look at a migration of some variety later this year. We already have an Exchange hybrid setup with Office 365, and are considering just migrating our mail to there rather than an on-premise upgrade. What are some of the negatives/issues/things we'd lose going cloud vs on-prem? Main things I can think of are: -likely need more Internet bandwidth -won't have archival backups of stores/mailboxes -? DAMIEN SOLODOW Senior Systems Engineer 317.447.6033 (office) 317.447.6014 (fax) HARRISON COLLEGE
