Gre Tunnel

Unanswered Question
Sep 9th, 2007
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Has anybody notioced any incomapatibilty between IOS 12.3 and 12.4 in GRE tunnels?!!!

I can easilty make between 12.4s but tunnel wouldn't come up between a 12.3 and 12.4!!!

Exact ver of 12.3 is 12.3(20) and 12.4 is 12.4(9T)and also 12.4(15T)!!!

I know there are some bugs for 12.4(9T) but I found none related to GRE tunnels!!!!

Platforms are

7206 VXR---> 12.3(20)

878----> 12.4(15T) and 12.4(9T)


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Overall Rating: 1 (1 ratings)
aghaznavi Fri, 09/14/2007 - 13:31
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GRE encapsulation is a Layer 3 technique that allows datagrams to be encapsulated into IP packets at the WCCP-enabled router and then redirected to a Content Engine. At this intermediate destination, the datagrams are decapsulated and then routed to an origin server to satisfy the request in case of a cache miss. In doing so, the trip to the server appears to the inner datagrams as one hop. Usually, the redirected traffic using GRE encapsulation is referred to as GRE tunnel traffic. All redirection is handled by router software. Mask assignment is not recommended.

a.alekseev Fri, 09/14/2007 - 15:43
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What do you mean, GRE P2P or GRE multipoint?

reich.marshal Sat, 09/15/2007 - 02:08
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GRE P2P!!!

This GRE Tunnel is only to keep our traffic unaffected from our service prvoider(from a QOS point of view)!!!

Traffic is driven by a VRF through service provider and the Tunnel carries the VRF through!!

Actually I couldn't solve the problem and planning to upgrade the 7200 to 12.4 but the problem is (no) GD ver is released for 12.4!!!!

Thx anyway.


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