Load balancing & Reverse routing issue

qureshi_asrar · ‎10-08-2009

Hi,

Please find the attached. I am having 2 router-A & B, running in HSRP mode & both connecting to my Database server via Different MPLS ISP. Need to know , if my Router-A links goes down, how do my traffic will move via router-B & once the link is up,it should shift to normal.ie. on router A.

Also if i use a load balancer,will it be possible that what traffic travel via Rtr-A should take the same path. I mean reverse path via Rtr-A with load balancer.

Collin Clark · ‎10-08-2009

It will move over via your routing protocol. If I understand your LB question, yes it can go back via the same link it cam in on. Again this would be dependent on your routing protocol. You may need to make some adjustments so traffic flows the way you want.

qureshi_asrar · ‎10-08-2009

Sorry to inform you,My Branches are 800, 400 will go via Rtr-A & other 400 By Rtr-B. if my Router-A goes Down, then traffice will move via Rtr-B. So the load on router-B will increase i.e. CPU,memory utilization & also routing table size would be increase , what could be other possible solutions.

YANGCCIE4 · ‎10-08-2009

Hi, gureshi_asrar

>>how do my traffic will move via router-B & once the link is up

If your igp is ospf, you can change the cost or the distance to make it load balance, and the traffic will move back to router-A once it comes back,

hope it helps

Yang

YANGCCIE4 · ‎10-08-2009

Anther solution, I gave the higher standy priority for Router-A, so once the

Router-A comes back, it will be the active one,

Router-B#sh run int e0

Building configuration...

Current configuration : 162 bytes

!

interface Ethernet0

ip address 1.1.123.1 255.255.255.0

standby 1 ip 1.1.123.254

standby 1 preempt

standby 1 name For_server

standby 1 track Ethernet0

end

Router-A#sh run int e0/0

Building configuration...

Current configuration : 203 bytes

!

interface Ethernet0/0

ip address 1.1.123.2 255.255.255.0

half-duplex

standby 1 ip 1.1.123.254

standby 1 priority 105

standby 1 preempt

standby 1 name For_server

standby 1 track Ethernet0/0

end

hope this helps

Yang

Collin Clark · ‎10-08-2009

Policy based routing would work here.

http://www.cisco.com/en/US/products/ps6599/products_white_paper09186a00800a4409.shtml