archive_mode is enabled, completed WAL segments are sent to archive storage by setting archive_command. In addition to
off, to disable, there are two modes:
always. During normal operation, there is no difference between the two modes, but when set to
always the WAL archiver is enabled also during archive recovery or standby mode. In
always mode, all files restored from the archive or streamed with streaming replication will be archived (again). See continuous-archiving-in-standby for details.
archive_mode and archive_command are separate variables so that archive_command can be changed without leaving archiving mode. This parameter can only be set at server start.
archive_mode cannot be enabled when wal_level is set to