Greetings Jorge,
* Jorge Torralba (jorge.torralba@gmail.com) wrote:
> pg_dumpall: role name starting with "pg_" skipped
That message should also tell you what the role name was which was
skipped by pg_dumpall.
> Looking at the source looks like it was committed back in April.
>
> What was the reason for this and can the messages be suppressed?
This was added because it means that a role which exists in your pre-9.6
version of PG begins with "pg_" and is not included in the pg_dumpall
output.
The best way to address this is to rename your role to not include the
"pg_" prefix as that prefix is now reserved for system-defined roles
(just like schemas).
Thanks!
Stephen