On Mon, Jun 10, 2019 at 09:00:38AM +0300, Achilleas Mantzios wrote: > On 10/6/19 7:36 π.μ., Pawan Sharma wrote: >> What is the best way to upgrade from PostgreSQL 9.6 to PostgreSQL >> 11 instead of pg_upgrade. > > why not pg_upgrade ? If the size is near the 3TB mark as you say, > pg_upgrade is the fastest IMHO.
When it comes to upgrades, you could also look at logical replication. Unfortunately your origin version cannot do that. Have you looked at things like BDR or Slony? They are logical-based, meaning a lower downtime than pg_upgrade, but they take longer.
For 3TB pg_upgrade can also be very fast if you use --link. Be wary of having backups though, all the time. -- Michael