Postgresql 10 replication mode error - postgresql

Question

I'm trying to setup a basic master slave configuration using streaming replication for postgres 10 and docker
Since the official docker image provides a docker-entrypoint-initdb.d folder for placing initialization scripts i thought it would be a swell idea to start placing my preparation code here.
What i'm trying to do is automate the way the database is restored before starting the slave in standby mode, so i run
rm -rf /var/lib/postgresql/data/* && pg_basebackup 'host=postgres-master port=5432 user=foo password=foo' -D /var/lib/postgresql/data/
and this succeeds.
Then the server is shutdown and restarted as per the docker initialization script, which pops up a message saying
database system identifier differs between the primary and standby
Now I've been sitting online for a while now, and the only 2 explanations i got is that I either have a misconfigured recovery.conf file, which looks like this
standby_mode = 'on'
primary_conninfo = 'host=postgres-master port=5432 user=foo password=foo'
trigger_file = '/tmp/postgresql.trigger'
Where the connection string is the same one i used for the base backup.
The second solution circulating is that the backup command could be messed up, but the only thing i add to the data folder after backup is the recovery.conf file.
Anyone have any idea where i'm messing up?
Should i just go for repmgr and call it a day?
Thanks in advance

Answer 1

To give an answer to my own question, the issue lied in how the dockerfile entrypoint scripts were called. Rather, they would end up starting the instance as a master or slave according to variables that were not properly set by me.