Is it possible to DR to another version of FDB cluster?

Using FoundationDB
1

For example, is it possible to run DR from a 6.2 cluster to another 6.3 cluster?

Thanks

2

For DR to function, the clusters need to have the same major/minor version, though they can have different patch versions. That means that DR won’t operate between 6.2 and 6.3.

It is worth noting that if you have DR running on two clusters and want to upgrade them, it is possible to do the upgrades non-simultaneously without stopping the DR. When you upgrade the first cluster, the DR will cease being able to send updates between them, meaning the secondary will start to fall behind. When you upgrade the second cluster, the DR will resume and try to catch back up. How far apart you can space them depends on how much lag you can tolerate and how much space you have on the primary cluster to store the mutations that need to be transmitted to the destination.

3

My understanding that it’s due to dr_agent or fdbdr won’t connect to different version clusters at the same time? But I am surprised that how it works in the upgrade scenario you mentioned. Is there any specific steps we need to follow? Thanks!

4

My understanding that it’s due to dr_agent or fdbdr won’t connect to different version clusters at the same time

That’s correct

But I am surprised that how it works in the upgrade scenario you mentioned. Is there any specific steps we need to follow?

I haven’t done this personally in a while, but if memory serves me you need to start the DR while the two clusters have matching versions. At that point, there’s nothing really special you need to do, and you can upgrade the clusters (along with their associated DR agents) as you wish. Once you have the clusters and your DR agents all running at the same version again, they will be able to connect and resume where they left off.