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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REL9_5_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/5d2e18d6ec3bdc042a37b1a9e577679e4b829bea
Modified Files
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doc/src/sgml/ref/pgupgrade.sgml | 38 ++++++++++++++++++++++++--------------
1 file changed, 24 insertions(+), 14 deletions(-)