It seems pure raft based on pysyncobj does not namespace the configuration values like e.g. etcd does (which uses the /$SCOPE/ as prefix/namespace). So you can't run two patroni instances on the same raft port.

Is this not possible due to restrictions in the way the key-value store works (no directories/nesting), or even due to the fact that it would be intrinsically tied to the patroni instance creating it (maybe like the systemid in postgresql)?

It would of course be possible to just select a different port for each instance, but this makes it more cumbersome to setup multiple instances the way Debian does it, because it currently assumes the DCS configuration is the same for each patroni instance.

As an aside, is there some default port assigned for raft? I see both 1234 and 222[234] in the code.

Maybe it could be made to just use API port + 10000 (so 18008 by default) if no port is specified, (assuming that this class could even get at the API port)?