provide redundancy in WAN environment????

[CHN]

hello,

my company want to provide redundancy at distribution layer in ISP environment.and to facilitate redundanct links ,they want to implement load sharing or load balancing like HSRP or GLBP.

as i know ,HSRP and GLBP are LAN protocol,they can't be used because their hello packet's TTL is 1.

i think route-map may solve this problem,but it must be configured at access layer.and this more likely burden

the router .

the topolegy like this:

..|...............|

router1...router2 (distribution layer)

.....|........../

.....|........./

.....|......../

...access router

REQUIRE:provide redundancy at distribution layer and load sharing or balancing.

Q:can you give me some advice?

[jackyoung]

You are correct that HSRP & GLBP is for LAN only. You cannot use it in WAN. Therefore, you have to use routing protocol to provide the redundancy function. e.g. EIGRP, OSPF, equal cost static route, etc.

In your case, I believe there is routing protocol in place, you just need to enable or fine tune it as load-sharing is fine. However, you also need to consider the bandwidth of the uplinks from access to distribution, if they are not similiar but enabled w/ load-sharing, the traffic may be overloaded on the lower bandwidth link.

Check below for more info.

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094820.shtml

Hope this helps.