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New Member

Strange Layer 2 Connectivity issue

Hi all,

I have an HP BL460c blade enclosure with Virtual Connect Flex10 switch connecting to a 6509 running CAT OS via two separate LACP etherchannel groups, and each group has two 1GB links to the 6509. I am having some strange layer 2 connectivity issues with the blade server on the HP blade enclosure. From the HP blade server for some reason I am not able to ping another server (a regular HP 2U server) and both servers are connected to the same 6509 module and are on the same VLAN. And from the sniffer trace I learned that the issue has something to do with ARP. It seems like there is no ARP response when I try to ping. So I was able to come up with a workaround for the time being by manually add static ARP entry on both servers (HP blade server and the regular HP 2U server). At this point I suspect it's something with the LACP eitherchannel link between the 6509 and HP blade center but I don't know what would cause the issue.

I appreciate any inputs/suggestions !!! and thanks in advance !!!


New Member

Re: Strange Layer 2 Connectivity issue

Well, we have similiar construction here but with 10GBit. But do you see the MAC-address of the server on your 6509?

We had some ping problems one day too. Server A inside enclosure was not able to ping Server B outside. Only happening in one VLAN. All end up in a faulty SFP+ inside the Flex10. Maybe you should check for hardware issues too.

New Member

Re: Strange Layer 2 Connectivity issue

thanks Marko !!! I appreciate your response !!! This is an odd issue and it's killing me !!! HP is pretty much said, everything is fine on their end.

Yes, I do see the MAC address of all servers in the 6509. I can ping from anywhere but from blade server.

Let me know if you can think of anything else !!!

Thanks again !!