CSS redundancy configuration

[b.athanasiadis]

Currently we have one CSS in operation with web server farm directly attached.

I would like to set up a second CSS in a redundant configuration. I have been

asked to retain the current cluster IP address (VIP) and addressing of the

web servers both of which are public addresses in the same subnet.

I have been experimenting with some spare CSSs to implement the Active/Backup

configuration using redundant VIPs and interfaces however I am unable to achieve

this with the above requirements ie retaining the one subnet. The configuration

used in the lab is as follows:

------6509------CSS------second ethernet connection back to 6509----

I have also tried implementing GLSB but have only been successful using two VIPs

one for each CSS and content rule-base DNS.

Any suggestions would be much appreciated.

[Gilles Dufour]

If you have 1 CSS and just needs to add a redundant one next to it, it is not difficult.

You can do it without re-addressing anything.

I assume the servers are in vlan and connected to a catalyst.

The active CSS is also connected to the same catalyst with 2 interfaces, 1 in the server vlan and 1 in the external vlan.

All you have to do is connect the standby CSS the same way.

Assign a new ip address to the standby CSS.

Now, if you don't want to have to change the server default-gateway, if you have to assign a new ip address to the active CSS and reuse its old ip address as the redundant-interface ip address [the address will now be shared by the 2 CSS].

You can configure the same VIP on the standby CSS.

Configure VIP redundancy to inform the CSS that the VIP addresses are shared.

This is explained in the following document :

http://www.cisco.com/en/US/products/hw/contnetw/ps792/products_configuration_guide_chapter09186a00801ef304.html

Regards,

Gilles.

[b.athanasiadis]

Giles, thanks for the feedback.

Actually your feedback refers to our lab setup. The operational CSS only has one connection to the cat switch and web farm is directly attached. The VIP address and server addresses are in the same subnet.

I am trying to move the servers to the catalyst switch and have a second connection from the CSS back to the switch keeping the same IP addressing.

The standby CSS would also have two interfaces

connected to the switch.