with interconnecting the Cat3750(C3750-ADVIPSERVICESK9-M,Version 12.2(25)SEE4 with a distribution Cat6509(with MSFC card) that gives us access to a gateway router.
Between the two switches we only use switchport access mode with the same vlan-id on both sides.
Both switches have the corresponding L3 level through an SVI definition. The 3750 is configured also with a default 0.0.0.0. 0.0.0.0 to the next hope ip address(on the 6509). The extended ping executed to a network behind the gateway from the 3750 is fine when we source the ping from the vlan-id that interconnects the two switches but is 100% failed when we change the source SVI to a different one. It looks like a strange inter-vlan routing issue but for all locally defined VLANs and SVIs it works perfectly fine. Have you ever had such strange issues with the 3750s?
Thank you for your feedbacks.
Are you saying you have multiple SVI's on both the 6500 and the 3750 ?
If so unless you tell the 6500 how to route to the other SVI's on your 3750 then you will not be able to ping.
So you could run a routing protocol between your 3750's and your 6500 so they know about each others SVI's.
If you do have SVI's on both switches can i ask why you have interconnected them with a L2 vlan and not used routed ports ?