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New Member

GLBP issues with only one firewall?

We are attempting to enable GLBP on our two 2600 routers, each with a T1 link to the same provider. Will the load-balancing functionality be possible if all internal traffic is coming from a single PIX firewall?


Re: GLBP issues with only one firewall?

Hi there,


"... The AVG assigns a virtual MAC address to each member of the GLBP group. Each gateway assumes responsibility for forwarding packets sent to the virtual MAC address assigned to it by the AVG. These gateways are known as active virtual forwarders (AVFs) for their virtual MAC address.

The AVG is responsible for answering Address Resolution Protocol (ARP) requests for the virtual IP address. Load sharing is achieved by the AVG replying to the ARP requests with different virtual MAC addresses."

So your PIX will get the common default gateway IP and ONE MAC address in an ARP reply. and this router will forward the packets.

So that means you have to setup routing to do the load sharing across your two WAN links. GLBP towards your PIX will not do it, if I understand the statements above.



New Member

Re: GLBP issues with only one firewall?

give desing ? where is the pix in the picture? where are the 2600 basically glbp works with loadbalancing gateways based on the PCs Mac addresses, therefore your 2600 have to be the GLBP default gateway of your PCs. If you have your PCs behind another L3 device it cannot work.