Re: How to start slave after pg_basebackup. Why min_wal_size and wal_keep_segments are duplicated

Hi!

> On 31. May, 2020, at 21:47, Andrus <kobruleht2@hot.ee> wrote:
> replikaator@[unknown] ERROR:  requested WAL segment 00000001000002CF000000E9 has already been removed
>the message says it all. You need to copy the WAL file 00000001000002CF000000E9 and newer to the replica's pg_wal
directorybecause 
 
>it has been removed >already on the master site.
>Obviously, you can only do that if the files have been archived.

wal files are not archieved.

>Otherwise, you'd have to fully reinitiate the replica.

I have tried to re-initiate replica serveral times in low-use time but this error occurs again.

>Replication will start again as soon as the requested WALs are copied over to the replica.
>Use a replication slot to avoid this situation. If you use a replication slot, the master will only remove WAL files
whichare not 
 
>needed by any one replica.

If named replication slot is used commands like

vacuumdb --all --full

will cause main server crash due to disk space limit. pg_wal directory will occupy free disk space. After that main
serverstops.
 

I tried using wal_keep_segments =180
Will setting wal_keep_segments to higher value allw replication start after pg_basebackup ?

Andrus.