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New Member

BGP with Private AS number

Dear All,

I have to take 2 internet connections from 2 different ISPs so that i have to run BGP in my network.But i dont have my own AS number.Is it possible to config BGP with Private AS.Will fallback work in this case.

TIA

Regards

SAM

4 REPLIES
Purple

Re: BGP with Private AS number

Sam,

In such cases, it may be pretty hard to use a private AS# since both ISPs will have to agree to use the same AS#. However, if getting a public AS# is not possible, you can still use private AS#s. If the two ISPs cannot agree on a common AS#, you can use the "local-as" feature to translate your AS# for one of the ISPs.

Hope that helps - pls do rate the post if it does.

Paresh

New Member

Re: BGP with Private AS number

Hi Sam,

if you plan to multihome to 2 different ISPs, using a private AS is not recommended. However there are ways how to do it with private AS...

1. Both ISPs need to support peering with a private AS (you)(some don't)

2. You need to agree a unique AS number that will suite both providers.

3. You will also need to advertise unique public network to each of them that usualy belongs to their address space.

4. If you've got your own public network, it's hard to make it work with private AS

Hope this helps,

M.

Re: BGP with Private AS number

Hi Sam,

If you already have a Public network space say from APNIC or ARIN, then just ask them to provide you an AS number.

If you dont have your own public network, then one ISP will not accept the other ISP's address block.

Narayan

New Member

Re: BGP with Private AS number

Dear all,

Thanks a lot for your kind & quick replies .

Let me discuss this issue with my both service providers.

Thanks & Regards

SAM

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