two default static routes
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03-27-2012 08:25 PM - edited 03-04-2019 03:49 PM
Hello ,
I have a internet router 2921 .my isp is providing 100 mbps internet link with static public ip network .I am using a default static route to the isp wan ip .I am planning to upgrade 100 mbps to 114 mbps .Unfortunately my isp doesnt have gig port in their side .So they are ready to provide two 57 mbps line .
Isp agreed they will route my public ip networks in both the links .
As a result i have two 54 mbps link with same network with two wan networks .My question is whether two default static route to both wan ip will carry out the load sharing correctly ?
Eg :
172.24.66.0 255.255.255.252 -first link my fa0/1 172.24.66.1
172.24.66.4 255.255.255.252 -second link my fa0/2 172.24.66.5
ip route 0.0.0.0 0.0.0.0 172.24.66.2
ip route 0.0.0.0 0.0.0.0 172.24.66.6
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03-27-2012 08:49 PM
Hi Sujeendran,
What do you mean about "load sharing correctly?".
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03-27-2012 08:56 PM
Hello frnd
i meant my traffic should utilize the both the links .I need to get the advantage of 114 mbps (57+ 57).Here my internet traffic is very high.
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03-27-2012 09:30 PM
anyone please help
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03-27-2012 11:23 PM
if the ISP link can be configured as L3 port channel from your end and their end
then you will need one default route point to the ISP IP that is configured on the port channel interfaces that uses both physical interfaces
if this is not possible then using two differnt L3 links to the ISP with differnt routes wil lead to asymmetrical routing where the inbound traffic use one link and the outbound might use the other link and could cause some issues !
a test is required but it is not the best way to be done for bonding two physical links
hope this help
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03-27-2012 11:27 PM
Hi,
of course the router will do load-balancing and for traffic forwarded by the router by default it will be CEF switched so per
session load-balanced and traffic originated by the router will be process-switched so per packet load-balanced.
You can change the behaviour for forwarded traffic by issuing the interface command: ip load-sharing per-packet
But don't do this if you've got voice or video traffic because you'll get into trouble due to out of order packets coming to destination.
Regards.
Alain
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03-28-2012 12:00 AM
Hi Sujeendran,
It is not clear to me how your router is connected with the ISP (e.g. to one or two ISP router)
Please read the next cisco link. It will be very helpful for your case since it covers all the cases and definetely and yours case.
http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a00800945bf.shtml
Hope that helps!
Vasilis
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03-28-2012 12:19 AM
Thanks to all for the support
hello vasillis
i am connecting the links to the same isp router
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03-28-2012 12:26 AM
So you should focus on the next
Load Sharing with the Loopback Address as a BGP Neighbor
to the next link
http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a00800945bf.shtml
Regards,
Vasilis
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03-28-2012 12:44 AM
hello vasillis,
Load Sharing with the Loopback Address as a BGP Neighbor
If am doing the above , is any extra configuration required for bandwidth .In my two links 4 networks are coming .
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03-28-2012 01:47 AM
Hi Sujeendran,
With the above configuration the traffic is shared between the links since you will have equal routes to the next hop. Do you have BGP peering with the ISP?
What are these 4 networks? Summary routes?
It should be noted that this configuration should be applied both to your router and ISP router in order to load balnce the traffic in both direction,
hope that helps
Vasilis
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03-28-2012 02:11 AM
you mentioned two interfaces to one ISP router
if those interfaces using differnt IPs peering with ISP router interfaces, then your router will perform loadbalancing to the traffic as mentioned above using CEF
however the issue here as i stated above that you do not know how the ISP router will loadbalnce the traffic back to your router and here where you may get asymmetrical routing !
if you can use eBGP with the ISP router using multi hop eBGP using loopback as a bgp neighbor IP then this might look better interims of loadbamcing or load sharing of the traffic ( per flow )
other than this you might need to consider L3 port channel between you router and the ISP router !!
hope this help
pls rate the helpful posts
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04-03-2012 02:03 AM
Hello frnds ,
I didnt enable the bgp .Now i only enabled the static routes .and also enabled the ip load-sharing per-packet and ip cef in the wan interfaces .
results
1.Traffic going through both the links
2.The traffic from the isp is equally load sharing in the links
3, Also the bandwidh out from my interface is not equally load shared .
4, Also the internet is getting slow
What may be the cause for the above..Is
eBGP with the ISP router using multi hop eBGP is required for this ?
