[60349] in North American Network Operators' Group
Re: Server Redundancy
daemon@ATHENA.MIT.EDU (Paul Vixie)
Thu Aug 7 03:11:30 2003
To: nanog@merit.edu
From: Paul Vixie <vixie@vix.com>
Date: 07 Aug 2003 07:06:35 +0000
In-Reply-To: <3F315F9C.17040.13D629F@localhost>
Errors-To: owner-nanog-outgoing@merit.edu
jason@ifuture.com ("Jason Robertson") writes:
> If you go out and spend a few thousand you can also get Allied Telesyn
> L2-L4 products that now support Load Balancing. Actually the rapier
> 24i is about $2000 Canadian. (I'd have to check the VAR pricing)
how much would i have to pay to not have that extra powered box between
my data and my customers?
oh, i forgot, it's zero, isn't it?
re:
> > Using outboard appliances for "server load balancing" is unnecessary,
> > and it adds more powered boxes (thus decreasing theoretical reliability).
> >
> > If your upstream router can speak OSPF and is made by either Cisco or
> > Juniper then it will implement ECMP (equal cost multipath). If you put
> > your "service address" on lo0 as an alias, and you run Zebra or GateD
> > on the "service hosts" which possess that alias address, then each such
> > host will appear to be a router toward the service address as a "stub host"
> > and your upstream routers will dtrt wrt flow hashing for udp or tcp traffic
> > (that is, the udp/tcp port number will figure into the hash function, so
> > you won't multipath your tcp sessions.)
> >
> > This is how f-root has worked for years. Look ma, no appliances.
--
Paul Vixie
