Over the Christmas break I migrated our on premises TFS 2015 instance to VSTS. The reason for the migration was multi-fold:
- We were blocked on moving to TFS 2017 as we could not easily upgrade our SQL cluster to SQL 2014
- We wanted to be on the latest, greatest and newest features of VSTS/TFS
- We wanted to get away from having to perform on-premises updates every few months
To do the migration we used the public preview of the TFS to VSTS Migrator.
So what did we learn?
The actual import was fairly quick, around 3 hours for just short of 200Gb of TPC data. However, getting the data from our on-premises system up to Azure was much slower, constrained by the need to copy backups around our LAN and our Internet bandwidth to get the files to Azure storage, a grand total of more like 16 hours. But remember this was mostly spent watching various progress bars after running various commands; so I was free to enjoy the Christmas break, I was not a slave to a PC.
This all makes it sound easy, and to be honest the actual production migration was, but this was only due to doing the hard work prior to the Christmas break during the dry run phase. During the dry run we:
- Addressed the TFS customisations that needed to be altered/removed
- Sorted the AD > AAD sync mappings for user accounts
- Worked out the backup/restore/copy process to get the TPC data to somewhere VSTS could import it from
- Did the actual dry run migration
- Tested the dry run instance after the migrate to get a list of what else needed addressing and anything our staff would have to do to access the new VSTS instance
- Documented (and scripted where possible) all the steps
- Made sure we had fall back processes in place if the migration failed.
And arguably most importantly, discovered how long each step would take so we could set expectations. This was the prime reason for picking the Christmas break as we knew we could have a number of days where there should be no TFS activity (we close for an extended period) hence de-risking the process to a great degree. We knew we could get the migration done over weekend, but a weeks break was easier, more relaxed, Christmas seemed a timely choice.
You might ask the question ‘what did not migrate?’
Well a better question might be ’what needed changing due to the migration?’
It was not so much items did not migrate, just they are handled a bit differently in VSTS. The list of areas we needed to address were
- User Licensing – we needed to make sure your user’s MSDN subscription are mapped to their work IDs.
- Build/Release Licensing – we needed to decide how many private build agents we really needed (not just spin up more on a whim as we had done with our on-premises TFS), they cost money on VSTS
- Release pipeline – now these don’t migrate as of the time of writing, but I wrote a quick tool to get 95% of their content moved. After using this tool we did then need to also edit the pipelines, re-entering ‘secrets’ which are not exported, before retesting them
But that was all the issues we had to address, everything else seems to be fine with users just changing the URL they connected to from on-premises to VSTS.
So if you think migrating your TFS to VSTS seems like a good idea, why not have a look at the blog post and video on the Microsoft ALM Blog about the migration tool. Remember that this is a Microsoft Gold DevOps Partner led process, so please get in touch with us at Black Marble or me directly via this blog if you want a chat about the migrations or other DevOps service we offer.