docs: improve pg_upgrade rsync instructions
This explains how rsync accomplishes updating standby servers and
clarifies the instructions.
Reported-by: Andreas Joseph Krogh
Discussion: https://postgr.es/m/VisenaEmail.10.2b4049e43870bd16.15d898d696f@tc7-visena
Backpatch-through: 9.5
Branch
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REL_10_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/b1705f35f805933629520eded68b82d2a2900871
Modified Files
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doc/src/sgml/ref/pgupgrade.sgml | 40 ++++++++++++++++++++++++----------------
1 file changed, 24 insertions(+), 16 deletions(-)