Kurt Seel <kseel(at)utcorp(dot)com> writes:
> I once tried to run two (6.? series) servers on one machine.
> They stepped on each others shared memory. I would like to
> transition to Postgres 7 one customer (database) at a time, so
> I am wondering if there is a way to run Pg 6.? and Pg 7 on the
> same machine?
I do that all the time. As long as you give each server its own
data directory and its own port number, they won't conflict.
AFAIK that's always been true --- but there didn't use to be an
interlock to prevent you from trying to start two servers with
conflicting port numbers, so if you screwed up a shared-memory
clobber might well be the first symptom of the mistake.
regards, tom lane