Re: Multihoming an end user
Pete Templin wrote:
Mailing List wrote:
We're a small shop in regards to needed address space. In other
words, a full blown BGP4/ASN with a /20 allocation from ARIN isn't
likely to be justified. Can this be done using a private ASN?
How big is your address usage?
Since we're able to NAT almost everything, a /29 is more then sufficient.
Keep in mind that ASN allocation and direct-from-ARIN address
allocation are two separate entities. You can get an ASN if you are
multihomed, about to multihome, or otherwise have a unique routing
policy from your provider; it has nothing to do with how many
addresses you have. With regards to addresses, you only need a /24 to
successfully multihome, and you can get a /24 from your ISP. Even if
you don't have enough usage to directly justify a /24, you can meet
ARIN's justification requirements by multihoming (you can only get one
/24 that way, and you'll have to allow all of your ISPs to check with
each other on that). If you're big enough to justify a /22, you can
get a /22 out of a bigger ARIN block for multihomed
My understanding was that if the addresses weren't specifically
allocated to us straight from ARIN, we couldn't truly multihome.
Otherwise our second ISP would try to route to our first ISP's addresses
through that first ISP rather then direct through their link to us. If
we apply for an ASN, can we associate our first ISP's /29 (or /24 if
need be) to our ASN? Does our primary ISP need to release it to us or
be multihomed themselves?
Once this is all said and done, is BGP4 on zebra the way to go or is
there something better?
Thanks for your help Pete!