I asked here a while ago in here about my inability to make physical mariabackups viable in a new server, it would eventually fail a restart ( i had a test that failed that led me to look into this).  This was in one AWS environment(VPC).  In the end there were no disk problems, no corrupt tables, no read issues with aria or innodbcheck as well as an online check with mysqlcheck.  And as i said in the earlier email, it works perfect in staging.

Some of you may remember that.  Anyway, to my satisfaction, i have solved that problem, and its more scorched earth solution than anything, happy to elaborate after.

No I have two very stable slaves set in strict gtid mode and I want to add them to the cluster that i am having an issue with, eventually retiring old nodes.  I have brought up new cluster nodes on so many occasions, but never transitioned from a replica and i don't trust the output of the current cluster SSTs, but it may work now, with my new setups.  I'll test that and ask this at the same time. 

I can layout a base plan for what i would do, but i'm asking for folks that have had to deal with this to compare my notes with. 

- All servers in the same VPC, spread across AZs, all IAM roles/policies fully in place.

- These are mariadb/galera nodes, not members of an RDS cluster.  I had needs that RDS didn't have when i built out this layout, in case you're curious or want to say move to RDS.

Thanks if you have pointers.  This is all mariadb 10.4.12/13. 

If i can tie this one up, i can release a bunch of simple set of bash scripts but make it safe to run on clusters, regardless if you're testing or provisioning, even as a pipiline test.

Thanks again,