Hi, I encountered an issue this weeked and was wondering if there is a simple solution to avoid this specific problem.
A simplified database setup here i three servers, which uses streaming replication with replication slot on pg10.1 M: a "master" server C: a hot standby that cascades to ... S: a slave. So data data flow is M -> C -> S. There is a replication slot for C on M - and a slot for S on C. S was taken down for mainenance - and during this window C suffered a hardware failure which redered the machine dead. Switching S to restore from M instead of C lead to missing WAL files, since the lsn for the C slot on M had already passed to lsn on S. So - is there a way to pass the cascaded info upstream? E.g. is there a way to non-manually make sure the WAL files on M are present for both C and S? (Hopefully this understandable)
