Re: How to acheive redundancy?

ganesh_nagar · ‎09-02-2002

Hi

I have my site connected to two different ISPs, and got 2 different IP blocks. Currently I am using Route policy (PBR) to route the traffic across the links by matching source IP addresses. If any link problem/high latency happens at one of the ISPs I am changing the default gateway of my proxy servers (configured public IPs) to the active ISP.

Can I do some thing on the router to route the packets automatically through the other ISP if one of the ISP goes down.?

or Do i need to get AS no and implement BGP for achevie this redundancy?

Thanks in Advance

Ganesh

srizkalla · ‎09-03-2002

Hi Ganesh,

You can also achieve this by using weighted static routes. i.e. point a default route to one ISP with a specific precedence, and the other default rout with a higher precendence. Your traffic should automatically switch if the link goes down to your primary ISP. The route will be withdrawn from your routing table.

Regards

SR

ganesh_nagar · ‎09-03-2002

Hi Sr

Thanks for your response. but this won't work, because its connected to 2 different ISPs and having 2 different IP addresses range. Some other ways should be there to achieve this!!

Thanks

Ganesh

jwitherell · ‎09-04-2002

You need the AS and BGP. Unless anyone else has any smooth ideas?

ganesh_nagar · ‎09-06-2002

Hi

Using AS and BGP is the bestway of doing it. In my setup I would need redundancy for traffic intiating from our end. let say If one link is down people should still continuing browsing through the other link.

I read one article saying that we can configure NAT 2 pool of ip ranges and can configure it to assign IPs to workstations dynamically. Is that possible? If so can some one give me a sample config?

Thanks

Ganesh

daniel.kline · ‎09-08-2002

If you want redundancy for outbound traffic, try looking into HSRP or Multigroup HSRP (MHSRP). To provide redundancy for traffic originating on the Internet (inbound traffic) you will need BGP. You can also acheive failover capabilities for inbound traffic by talking to you service provider about adding duplicate entries in you DNS record for your mail and Web servers.

Dan