Dual Chassis configuration

[ghassanovich]

Gooday,

I am designing a network architecture in which redundancy and high availability are a crutial issues. I have chosen to connect multiple servers and workstations to switch modules in one chassis. A second chassis will be the bakup of the first one: it contains identical mangement and switch modules.

The issue is that I don't want to connect the servers, and workstations to both chassis. the ideal is to have connexions to just the first chassis, which will be interconnected to the second one.

I looked for such configuration in cisco site,and in the net but, I didn't find any.

I wonder if such possible configuration existes, and if so, which products (cisco's or else) implement it.

I searched all catalyst 6500 documentation. but in vain

I will extremely apperciate your help.

regards,

[7rbowenii]

Could you please explian to me the redundancy and high-availibility afforded when all your end-stations have the smae single point of failure? What is the purpose of the second chassis, if it's not actually doing anything but sitting there.

My understanding of this configuration is that if the primary chassis fails, someone has to manually move the connections from one chassis to the other. Befoer we go too miuch further, let me know if I'm on track...

-bo

[ghassanovich]

Actually the redundancy, and high availability is what I want to acheive. there are two ways to do it.

in both of them the two chassis are interconnected. the first way is to have all my end-stations connected to two different chassis (to the two relevant modules) via two network interface cards. the second way (and I don't knwo if it's possible: that's what I'm actually asking) is to have the end stations connected only to the modules of the first chassis, and since this one is "interconnected" to the second chassis, I wonder if it's possible in case of failure of one switching module (or if you may call it interface card) that the "supervisor or management module" switches all the connections of that modules to the same identical module in the other chassis via, of course, the link.

in other words, is it sufficient to have one link between the two chassis to asuure availability or must we have individual connections to both of them.

I hope that I clarified the situation

[7rbowenii]

That's really going to depend on the SLA (Service level agreement) that you're tryint to provide. If all of your connections are in the same module of a single chassis, if that mod or chassis goes down, you lose everything. A link to another chassis buys you nothing. If you put some of your resources on different modules in a chassis, you protect yourself from a module failure in that you won't lose everything. However, if the chassis goes down, you've lost everything and your single link to the second chassis acheives nothing.

I believe that what you are asking is if you have a connection from switch A, card 2 to switch B card 2 will the connections in switch A be serviced by switch B in the event of an outage of either switch A or Card 2? If this is the question, then the answer is no. However, this answer could be a bit different if you are using 3750's stacking capabilities.