[Maas-devel] Replacing Apache

[Christian Robottom Reis]

On Thu, Nov 27, 2014 at 03:56:17PM +0000, Gavin Panella wrote:
> >     - There is a bug filed by IS asking us to reduce the number of ports
> >       the region listens on. Could we bing all region processes to the
> >       same socket using SO_REUSEPORT to avoid this issue?
> >
> >         http://lwn.net/Articles/542629/
> >
> >       We'd need to study the semantics, but this seems easier than
> >       inverting it so the region connects to the cluster.
> 
> Each clusterd needs to connect to each regiond. Having multiple regionds
> listening (for RPC) on the same port makes it hit-and-miss for a
> clusterd to make all of the connections it needs. It could just keep
> trying until it has them all, but that's a bit sucky.

Yeah, I had forgotten about that aspect of the architecture, which is
tied to having multiple active region processes (possibly spread across
multiple machines). Is there a reason why we need that, and couldn't
move to a passive failover model?

> "Hello! Is that regiond-B?"
> 
> "No, this is regiond-A, and I'm already talking to you on line 1."
> 
> <click>
> 
> "Hello! Is that regiond-B?"
> 
> "No, this is regiond-A, and I just spoke to you."
> 
> <click>
> 
> "Hello? ..."
> 
> We could turn this around and make each regiond initiate connections to
> each clusterd, and that would address the problem... as long as we only
> have one clusterd on each cluster controller.

Is there a realistic scenario where we will have more than one?
-- 
Christian Robottom Reis   | [+1] 612 888 4935    | http://launchpad.net/~kiko
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