Two ISPs & PIX 520

[knikolovski]

My name is Oliver Aleksovski and my company Makpetrol-Skopje, Macedonia) is CISCO resseler for now, but we have plans to become better partner. Now, here is our problem at one of our custommers: We already have CISCO 1720, with 1 serial connection to Internet (62 IP = adresses with NAT in the PIX). Behind the router there is PIX 520 with DMZ card - Mail Server. Now we have one more connection to Internet available (another 62 IP addresses). How should we use it best (load balancing, faster connection...) Should we take more NICs in the PIX or?

[jrevald]

Hi,

In order for you to load balance multihoming (connecting to two ISP at the same time) you would need to run some form of routing protocol on your router. You have two options. Either see if the two ISP's would agree to run some form of IGP routing protocol between them and you, like OSPF, or configure BGP on your router and use your own AS number.

Now, the last option is not going to be useful at all with a small router. You need a serious amount of computing power and RAM for BGP to work like you would want it to (7100/7200). BGP also requires a thorough understanding before you begin on such an adventure.

My advice to you would be to either see if your ISP's would agree to use OSPF or simply settle for one ISP.

The pix itself does not know how to route to different ISP's dynamically (well it does through RIP, but that isn't exactly an option for multihoming).

Best regards,

Jesper Revald