Dear Amit, Robert,
> So, we have the following options: (a) by default drop the
> pre-existing subscriptions, (b) by default disable the pre-existing
> subscriptions, and add a Note in the docs that users can take
> necessary actions to enable or drop them. Now, we can even think of
> providing a switch to retain the pre-existing subscriptions or
> publications as the user may have some use case where it can be
> helpful for her. For example, retaining publications can help in
> creating a bi-directional setup.
Another point we should consider is the replication slot. If standby server has
had slots and they were forgotten, WAL files won't be discarded so disk full
failure will happen. v2-0004 proposed in [1] drops replication slots when their
failover option is true. This can partially solve the issue, but what should be
for other slots?
[1]: https://www.postgresql.org/message-id/CANhcyEV6q1Vhd37i1axUeScLi0UAGVxta1LDa0BV0Eh--TcPMg%40mail.gmail.com
Best Regards,
Hayato Kuroda
FUJITSU LIMITED
https://www.fujitsu.com/