BGP (Seems a popular Subject)

[Maverick8673]

I am wanting to implement BGP in my network scheme. What BGP route is adviseable.

IE:If you want to receive the full Internet routing table, use the Configuration to Receive Full Internet Routing Table on your local router (Router A in the examples in this document).

If you want to receive routes that are directly connected to your service providers, but use default routes to the rest of the Internet, try the Configuration to Receive Directly-Connected Routes.

If you want to receive only default routes from the directly connected service providers, use the Configuration to Receive Default Routes Only.

Which way is better or in what case would you use each of these?

 

[wybnormal]

Not to be offensive but if you are having to ask which BGP schema to use, you should really rethink your approach. BGP is pretty unforgiving with errors and if your BGP is facing the outside, you can find yourself in a blackhole after an error pretty fast.

Most companies use EIGRP or OSPF and then a very limited BGP configuration facing their ISP. THe ISP provides most of the configuration to assure it is correct and it only exchanges information with the ISP's routers.

The only real problem I've seen with ISP doing this is that they normally give you a single AS which makes it tough to load balance. Not imposible but more difficult than it should be.

MikeS

http://www.packetattack.com

http://www.packetpress.net

Home of the book "Network Security Using Linux"

 

[jneiberger]

I agree with wybnormal. If this is for a production connection, and it sounds like it is, then you should really make sure you have someone available who understands BGP to configure it. This isn't something you want to mess around with. It isn't *that* hard, but it's very, very easy to do lots of bad things that you didn't intend.

John

 

[Maverick8673]

What I really need to know is what method is most used for ISP redundancy. I am aware of all the in's and out's and could possibly get a tech that is more familiar with the area, Just would like to get the basic information here.

 

[KiscoKid]

Options available inc (going from least resilient to most resilient):

1. Single router/Single ISP (95% availability?)
2. Single router/Dual ISP (97% availability?)
3. Dual router/Single ISP (99% availability?)
4. Dual router/Dual ISP (99.99% availability?)

Which method you goes with is a decision best reached with the customer and typically involves two points of consideration: 'Cost to Implement' (the solutions above get steadily more expensive than the previous one) and 'Business Impact Failure'.

A company should be able to assess how much money they would lose per hour in the event of total loss of Internet service. You can then weight this up against the cost of each implementation above which will help guide in making the right choice.

 

[jneiberger]

As a side note, it should be noted that it is not even necessary to run BGP if you only have one ISP, even with multiple connections.

 

[Maverick8673]

It will be 2 isp's and hopefully 2 routers. as I like the 99.9% availibility Kiscokid mentioned.