logical replication upgrades.
Backpatch to 9.2.
<para>
A Log-Shipping Standby Server (<xref linkend="warm-standby">) cannot
be upgraded because the server must allow writes. The simplest way
- is to upgrade the primary and use rsync to rebuild the standbys.
+ is to upgrade the primary and use <command>rsync</> to rebuild the
+ standbys. You can run <command>rsync</> while the primary is down,
+ or as part of a base backup (<xref linkend="backup-base-backup">)
+ which overwrites the old standby cluster.
</para>
<para>