Configure standby failing

While configuring a stand-by node, the process fails after sometime with a connection termination.

The standby node can reach the master in all 443, 5432 and 1999 ports and also has enough resources (memory/cpu).

root@01e46ffcc731:/# evoke unpack seed /root/standby.tar
tar: Removing leading `/’ from member names
Seed file was successfully unpacked.
Run ‘evoke configure standby’ or ‘evoke configure upgradable’ to configure this machine.

root@01e46ffcc731:/# evoke configure standby

psql: server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
psql: server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
error: Replication connection could not be established

root@01e46ffcc731:/# free -g
total used free shared buff/cache available
Mem: 15 0 13 0 1 14
Swap: 0 0 0

root@01e46ffcc731:/# nproc
4

root@01e46ffcc731:/# nc -v $master 443
Connection to $master 443 port [tcp/https] succeeded!
^C
root@01e46ffcc731:/# nc -v $master 5432
Connection to $master 5432 port [tcp/postgresql] succeeded!
^C
root@01e46ffcc731:/# nc -v $master 1999
Connection to $master 1999 port [tcp/*] succeeded!