Thanks elephatwalker :)
"elephantwalker" <[EMAIL PROTECTED]> on 07/07/2001 01:21:20 PM
Please respond to Orion-Interest <[EMAIL PROTECTED]>
To: Orion-Interest <[EMAIL PROTECTED]>
cc: (bcc: Gurinder Randhawa/Travel Underwriters)
Subject: RE: Cluster configuration
another resend...didn't catch second time around...
-----Original Message-----
From: elephantwalker [mailto:[EMAIL PROTECTED]]
Sent: Friday, July 06, 2001 11:41 PM
To: Orion-Interest
Subject: RE: Cluster configuration
resend...didn't catch the first time around...
-----Original Message-----
From: elephantwalker [mailto:[EMAIL PROTECTED]]
Sent: Friday, July 06, 2001 8:43 PM
To: Orion-Interest
Subject: RE: Cluster configuration
Gurinder,
The clusters are setup just to lighten the multi-cast traffic. That is, if
every server was sharing its http sessions with every other server, you can
see how the power of e and factorial are related. (sigma (1/n!)) == e. So
instead of the traffic being proporational e^s, where s is the number of
sessions, the traffic is proportional to s*n!, where n is the number of
servers in a cluster. If a cluster has three servers, this seems to be a
good comprimise between redundancy and multi-cast traffic.
The loadbalancing bit randomly picks servers ... not clusters. So if one
server goes down or is removed, another server in its same cluster takes
over. This is the fail-over policy.
regards,
the elephantwalker
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Gurinder
Randhawa
Sent: Friday, July 06, 2001 5:14 PM
To: Orion-Interest
Subject: Re: Cluster configuration
Thanks for the response Jeff, what i wanted was first and foremost was
if one orion instance fails another one to kick in with session
replication.
This sounds like a cluster island. I guess thats all i want.
But isn't a cluster-island used only for "fault tolerance" that is if one
instance
fails another one on the island picks it up with session replication ?
Can you distribute (load balance) in one cluster-island or do u need
multiple cluster islands? I want
fault tolerance and load balancing between instances (is this multiple
cluster islands ?).
What would be the best setup for this ? Sorry i think i might be just
confusing myself more.
If you could clear this up a little it would be great.
Thanks a bunch
Gurinder
Jeff Hubbach <[EMAIL PROTECTED]> on 07/06/2001 02:14:04 PM
Please respond to Orion-Interest <[EMAIL PROTECTED]>
To: Orion-Interest <[EMAIL PROTECTED]>
cc: (bcc: Gurinder Randhawa/Travel Underwriters)
Subject: Re: Cluster configuration
A cluster-island is just a cluster, because session replication doesn't
happen between cluster-islands, just inside it. So yes, you need at least 2
instances per cluster-island, and yes you install 2 separate orion
instances
with the same cluster id in the web-site.xml. I didn't run any benchmarks
on
my cluster setup, it was more just a proof-of-concept. Is there a reason
you
want 2 cluster-islands? because they won't share session information with
eachother.
Jeff.
Gurinder Randhawa wrote:
> One other question i had was...when you setup a "cluster-island"
> do you install 2 seperate orion instances with same cluster id in
> web-site.xml ?
>
> We are setting up 2 cluster-islands witha load balancer running behind
> apache
> on same host (one physical sun box) for one web-application. So to add to
> my question above
> for 2 cluster-islands do we need to run 4 instances of orion or just 2 ?
> The documentation wasn't
> clear to me on this....
>
> I have it working for a single instance of orion but need to do
clustering
> for scalability and
> fault tolerance issues. How does this perform ?
>
> Thanks
>
> Gurinder Randhawa
> Travel Underwriters Group Of Companies
> IS Department, Senior programmer/analyst
>
> Jeff Hubbach <[EMAIL PROTECTED]> on 07/06/2001 07:31:33 AM
>
> Please respond to Orion-Interest <[EMAIL PROTECTED]>
>
> To: Orion-Interest <[EMAIL PROTECTED]>
> cc: (bcc: Gurinder Randhawa/Travel Underwriters)
> Subject: Re: Cluster configuration
>
> There's a very nice how-to at:
> http://www.orionserver.com/docs/http-clustering.html
>
> Jeff.
>
> Alessandro Fustini wrote:
>
> > Hi,
> > I woul like configure a Orion cluster with 2 PC.
> > Is it only necessary change orion/application-deloyments/
> > default/defaultWebApp/orion-web.xml file with
> > <cluster-config /> add ??
> >
> > Thanks a lot for all help
> >
> >
> >
> > Alessandro Fustini
> > Java Developer
> >
> > e-mail: [EMAIL PROTECTED]
>
> --
> Jeff Hubbach
> Internet Developer
> New Media Designs, Inc.
> www.nmd.com
--
Jeff Hubbach
Internet Developer
New Media Designs, Inc.
www.nmd.com
