Re: started playing with jails


Bill Moran wrote:
In response to Greg Barniskis <nalists@xxxxxxxxxxxxxx>:

Bill Moran wrote:

I've had trouble getting programs that use shared memory (such as Postgres)
to run inside a jail, but it's been a while since I've tried.
Postgres needs this in the host rc.conf:

jail_sysvipc_allow="YES"

My experiments with Postgres in jail predate the existence of that setting.
When I was working with it, you had to frob a sysctl via /etc/sysctl.conf

But even then, I couldn't seem to get it to work -- the Postgres in the
jail would corrupt the shared memory of the postgres outside the jail.
It was ugly. Imagine big, wet tears rolling down my cheeks.

I haven't had the need to try it in a while, so it might work OK now, I
just don't know.


Ah, now that you mention it I do recall discussions of multiple
instances peeing in each others pools so to speak. I also thought
there was discussion of how to fix it, but have no idea where that
went if anywhere...

A single instance inside a jail does work quite happily if the knob
above is set.

--
Greg Barniskis, Computer Systems Integrator
South Central Library System (SCLS)
Library Interchange Network (LINK)
<gregb at scls.lib.wi.us>, (608) 266-6348

what is the best method for backup? just back up the whole thing as if it were
"files" on my host?

thanks,
jonathan

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