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New Member

load balancing & redundancy

Hi, suppose i have the following scenario :

R1 --- P2P link --- R3

|

X1

|

R2 --- P2P link --- R4

My objective is to do load balancing and redundancy between the 2 P2P links... The remote site has the same setup. X1 has a connection to the LAN.

Have thought of using 2 static route to interface on the X1, X2 to do it...

1) What kind of impact can i foresee?

2) Will the static routes be able to load balancing in case of heavy load on R1 or R2?

3) If X1 was to be a L2 switch, wat method can i use?

All suggestions are welcome... Thanks

-Steven-

4 REPLIES
Bronze

Re: load balancing & redundancy

If X1 is a router and you connected to your LAN and you have two static routes on it (one pointing to R1 and the other to R2) that point to the LAN on the other side of of the P2P links (the R3/R4 LAN), you will have a problem if one of the P2P links goes down. Say if the P2P link between R1 and R3 went down. X1 will not know that the link went down and will continue to send packets to R1.

Your best bet is to run a routing protocol like EIGRP on R1,R2,R3,R4 and X1. X1 will receive equal cost routes to the LAN on R3 and R4 and will load balance between them. Also enable CEF on X1. CEF supports per packet and per destination load balancing. You might want to read this before selecing which method to use:

http://www.cisco.com/en/US/tech/tk827/tk831/technologies_tech_note09186a0080094806.shtml#internalmech

HTH

New Member

Re: load balancing & redundancy

Hi HTH,

For X1, i intend to use ip route , so even if the interface goes down, the route via that particular interface will also disappear from the routing table, which means packets will route via the other interface. Am i right to say that?

Thanks,

Steven

Bronze

Re: load balancing & redundancy

Yes, but that just covers the links from X1 to R1 and from X1 to R2. If the p2p link between R1 and R3 or the p2p link between R2 and R4 go down, X1 will not know about it.

New Member

Re: load balancing & redundancy

yes, i see the picture now... Thanks alot.

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