Re: [Webware-discuss] scaling Webware up

[Federico Di G. <fo...@de...>]

On Thu, 2001-10-25 at 17:03, Geoff Talvola wrote:
> Now that we're talking about future work...
>=20
> For my use of Webware, a single box is more than enough horsepower.  But=20
> suppose I had to scale up to 2 or more boxes to handle the load and/or fo=
r=20
> redundancy.  How would I do it with Webware?  For that matter, how is it=20
> typically done with other systems like IIS with Active Server Pages or Ja=
va=20
> Servlets?  Is there some sort of front-end hardware or software that=20
> distributes the requests evenly to the different web servers?

when using zope (abandoned in favor of webware) we had the same problem.
we solved it by using 4 application server boxes + 1 db box + load
balancer box. the load balancer uses a modified kernel from the linux
virtual server project (http://www.linuxvirtualserver.org/) and balance
the incoming net load by rewriting packet headers. outgoing packets
(already mangled) go directly from the app servers to the client.=20
=20
> Would Webware support this now, or would it need to be enhanced?  The onl=
y=20
> problem area I can think of is session handling.  Fortunately, it would b=
e=20
> easy to write a session store that used a database back-end.  Or, without=
=20
> too much pain you could modify the adapters so that they always route=20
> requests for the same session to the same appserver.

sessions were hold on the db, but i think you can very easy write a
DistributedSession class that propagates and cache session data... the
lvs also has a configurable timeout to route incoming connections to the
same server, but with the large number of today masquerated hosts, you
don't usually get anywhere (i.e., one box overloaded, the others almost
idle...)

ciao,
federico

--=20
Federico Di Gregorio
Debian GNU/Linux Developer & Italian Press Contact        fo...@de...
INIT.D Developer                                           fo...@in...
                           Don't dream it. Be it. -- Dr. Frank'n'further