1.To add live HA to PG, I transfer WAL of a database instance(Primary node) to another database instance (standby
node)at real time, and keep startup alive in standby node to recovery WAL online,so that standby node can be a hot
standby.
But I got some trouble. When standby node switch to primary mode to accept connections, of course after startup
initilizethe WAL and exit, the postgres process ereportERROR
when mdread function enter ERROR branch, and I got message like this "could not read block X of relation X/X/X: read
onlyXof X bytes". I spent two days to figure out what happened, but it is too hard.Please help me.
2. When restore data from a LIVE backup , I got message like "unexpected pageaddr %X/%X in log file %u, segment %u,
offset%u" "WAL ends before end time of backup dump". It seems the WAL was
corrupted. I found the LSN where the error occured contained the wrong pageaddr, the pageaddr was 8K before it's real
address.Whatwas wrong?
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Richard
2010-08-04
