Experts , ps ur kind opinion in the design

[Ibrahim Jamil]

Hi Experts

my company now  needs to deploy ISP in 2 different region , region 1 and region 2 now two big ISPs will give us connections in each region

currently we obtain an AS number with with 4 class C Subnet from ripe.i need to advertise two of this subnet to ISPs in region 1 while the remaining two Subnet towards isps (ISPs provider are the same) in region 2 ,please note the same ISP provider also exist in region 1 ang region2 as well,

the above are the input , pls tell me the best design and the best setup to for succefull implemantion please see topology attached

i wondering, do i need any kind of ibgp between regions

thanks

jamil

[Marwan ALshawi]

Hi Jamil,

do you have any sort of backdoor link/connection between the regions not over the ISP ?

generally speaking you can achieve this by doing the below:

1- confirm with both ISPs about the range that you going to advertise from each region/link to make sure it will be allowed from there end

2- advertise the desired IP range from the relevant region router

3- if you want to have active/standby inbound traffic per region for both range in each region use AS path prepending

4- if you want load sharing you might use BGP policies to make one link active for one range and the other standby per region

5- use iBGP internally between the CE routers ( your side )

6- not sure what is in the LAN side as it need to be aligned with your routing polices for in and out

note:

you mentioned you will obtain AS number is that mean same as number for all CEs ?

see the below link for some config examples might help you

http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a00800945bf.shtml

hope this help

if helpful rate

[Ibrahim Jamil]

Hi Reza

Answer to ur questions:

1)do you have any sort of backdoor link/connection between the regions not over the ISP ?

i have 2 E1 s link between the 2 regions, i going to use it for ibgp?what ur recomendations?

note:

you mentioned you will obtain AS number is that mean same as number for all CEs ?

we already got  as from ripe along with 4 class c subnets

in term of BGP Multihoming what is the need of the Backdoor link betwwen region?

have y done such this setup?ps share ur gotchas

thanks

[Ibrahim Jamil]

Hi Reza

do i need IBGP Sessions between regions?

do i need any type of RR between Regions?

i want all links in each region passes traffic,since i pay for both , i dont want any link as standby

thanks

Jamil