Re: old and new pg_controldata WAL segment sizes are invalid or donot match

Hi ram,

> On 17. Jun, 2020, at 23:05, ram pratap maurya <rampratap0000@gmail.com> wrote:
> old and new pg_controldata WAL segment sizes are invalid or do not match
> Failure, exiting

delete the *new* PostgreSQL cluster (it should be empty anyway) and reinitialize it setting the wal-segsize to the same
asthe old cluster: 

$ initdb --wal-segsize=<size> ...

(see https://www.postgresql.org/docs/current/app-initdb.html)

Then perform the upgrade as you tried before.

After that, you can, if you want, reset the size to a new one using pg_resetwal. But make sure you first do a really
cleanbackup! 

$ pg_resetwal --wal-segsize=<new_size> ...
(see https://www.postgresql.org/docs/current/app-pgresetwal.html)

But know what you're doing! Try on a test database first to see how it works.

Cheers,
Paul