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Weird behavior between LANs

Weird behavior between LANs

Weird behavior between LANs

Hi guys,

I need help with an issue. Recently I figure out that I´ve been receiving high replies using ping.

As you could see on image, there is a layer 3 switch which is attached to each L2 switch. For some reason machines B, C are getting 80, 100, 125 ms responses but there are some exceptions, like A with 1ms.

Also, we have unmanageable switches, and machines attached to them are getting 1 ms responses.

What could be happening here ?


RE: Weird behavior between LANs

No image?

RE: Weird behavior between LANs

I would look try setting the port from Auto to 100mb/Full


RE: Weird behavior between LANs

Give us the "show cdp neighbour" from the L3 switch.

Give us the "show run interface ???" for each of the switch interconnect interfaces. (that's 4 of them, 1 from each L2 switch and 2 from the L3 switch)

Then give us a "show interface" for each of the same interfaces as above.

Give us a "show interface vlan ???" for each vlan mentioned on each interface on each of the switches.

Do not go around getting rid of auto-negotiate unless you have clear testing indicating this is required.

RE: Weird behavior between LANs

Also you can check the CPU usage of the L2 switch and use wireshark in the Vlan of machines B and C to see if something is flooding your network.

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