I plan to change the redundancy of an in-production 6.3.23 FDB database from
single on one machine to
double with 3 machines .
I did some tests locally with docker containers and everything worked fine so far
Still, I have concerns regarding the changing of redundancy.
First, I have to add additional machines to the cluster before changing the redundant mode.
Indeed, if running
fdbcli --exec "configure double" without adding 2 machines, an error
Not enough processes exist to support the specified configuration is raised.
As a result, I must add these machines first. But the consequence of adding additional machines when a database is in a
single redundant mode is that FDB should start partitioning the data across these machines :
singlemode will work with clusters of two or more computers and will partition data for increased performance but the cluster will not tolerate the loss of any machines.
In my opinion, it is unnecessary because I intend to change the redundant mode to
Also, I don’t know how FDB reacts to
fdbcli --exec "configure double" while already partitioning a large database .
1/ Is there a way to avoid the partitioning of the database between the addition of extra machines and the redundancy configuration change?
2/ What are the risks of changing the redundancy configuration when FDB is partitioning the data through the just added extra machines?
Thanks to all of you who take the time to help .