[CentOS] OT: CentOS server with 2 GbE links to 2 GbE switches

Fri Aug 26 19:11:44 UTC 2005
Scot L. Harris <webid at cfl.rr.com>

On Fri, 2005-08-26 at 13:23, Patrick wrote:
> On Fri, 2005-08-26 at 12:04 -0400, Scot L. Harris wrote:
> > 

> > Depending on the costs of taking an outage you may be better off having
> > a cold spare handy to replace the switch or device that fails.
> 
> The organization has simply decided there shall not be an outage of the
> service (which means indivual parts can blow up as long as the service
> remains up) so the cost of adding redundancy till you drop is not an
> issue. Obviously, next to the active redundancy, we could always add a
> few cold spares :)
> 
> Thanks for your comments and suggestions.

That is unusual. :)  Most of the time after designing a gold plated
redundant system with no single points of failure the customers look at
the cost and decide that they don't need things quite that bullet
proof.  :)

To achieve zero down time for the service you will need resolve that
clustering issue with the PBX software.  As you indicate that is going
to be difficult.  The closest I came to something like that was some
Checkpoint firewalls I had setup in a VRRP configuration.  They shared
the tables listing the connections being routed through them so if one
rolled over and the other took over the connections in theory would not
have to be reestablished through the backup firewall.  

Hopefully the asterisk software has a feature that will handle that for
you.  The other parts of the network can be built in a redundant mode.

Good luck!