CoreSwitch 4507 GLBP & Stacking.

[talhazubairi]

Hi,

I am in a process of implementing 4507 in a redundant environment. I have some issues while desgining the infrastucture and configuration and need help in order to implement.

1) I want to run GLBP between two 4507. Does 4500 series supports glbp? From a Cisco link it doesn't show me in the list? if so can some please post a link to it? What are the prerequsites?

2) I have three switches SW1, SW2 & SW3. They are configured with stacking. Now, when there is stacking the switches are configured as Primary and Secondry. So in this case SW1 is Primary. From SW1 they have a fiber connecting to the Primary Core switch. Customer wants to have a redundant link to the secondry Core switch. I am planning to have a fiber from SW3 to the second Core switch, but since this switch (SW3) is a secondry in configuration of stack, will it support the failover? will it become Primary if SW1 goes down or the fiber gets promlebatic? If so will there be additional configuration on those switches?

Thanks

TZ

[Harish Balakrishnan]

Hello Talha,

Let me try to answer your queries.

1. GLBP supported in 4500 as of 12.2.46 IOS release. Follow the below link to configure the same

http://www.cisco.com/en/US/docs/ios/ipapp/configuration/guide/ipapp_glbp_ps6350_TSD_Products_Configuration_Guide_Chapter.html#wp1054538

2, Since you have 3 switches stacked, stack itself give the hardware redundancy between the switches. one of the switch will be stack master and others are selected as memebers . In the event of the master fails, the next possible switch will become master. As you said it is perfect to connect the second link to sw3 from core switch2 and it will be in blocked mode since STP is running between stacks and core switches. In case if the primary switch or link fails, thesecondary link will get activiated in seconds and start swiching the traffic.

regards

Harish