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Not sure what happened to the switch

Dear sir,

Do you know what happened to the switch? I've checked seem to be ok with that switch.Hereby attached is the show tech-support, just need someone help here to verify any problems with the switch?

We are having issue intermittent connection lost from client pc(microsoft outlook) to mail server (microsoft exchange 5.5) . Please verify and advise.



Re: Not sure what happened to the switch


are the Exchange server and the clients in the same Vlan ? I noticed that you have configured all your port channels to ´mode on´; this is not recommended: when the `on´ mode is used, it will attempt

to unconditionally channel instead of negotiating the channel. The result depends on what code is running on the switch, and what features are enabled. It is possible that BPDUs can get lost down these unidirectional paths and in turn 802.1d will unblock a link that should be blocking. This can create a loop in the network where any broadcast traffic traversing the "good" link in the etherchannel will melt the network.

If your Exchange server is located in a different Vlan, try and configure:

ip tcp adjust-mss 1350

on all Vlan interfaces in the path between the client and the server.



Re: Not sure what happened to the switch

Could you give us more information on this issue?

where are the 2 host connected? on the same switch? which port?

Was this tech-support ran at the same time the problem was occuring?

how frequent is this problem happening?

when it lose the connectivity, how long it stays down?

Can you ping the server at the same time and check if you will lose icmp packtes during the problem?

Let us know,


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