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SPAN Port - RSPAN - Packet Fragmentation

Hi all,

I've a Catalyst Switch WS-C2960-24TT-L,

This switch in installed in the Buiding "B". I wanna copy traffic originating from 2 FastEthernet port of a switch in that building to a "Monitoring Server" located in the opposite building (Buiding "C").

The "Monitoring Server" is linked to the switch using the Giga Interface (Switch --> EthernetRJ45 --> Media Converter --> Fiber Optic --> Media Converter --> EthernetRJ45 --> "Monitoring Server").

I configured a Span Session for copying the traffic of the 2 FastEthernet Port to the Giga Interface but I got some problem to the “monitoring Server” side 'cause I can't receive the packet from the Giga Interface.

Using WireShark to switch side I can see the correct delivering of the packet outside span destination port, but I don't see the same traffic arriving to “Monitoring Server” side.

I discovered the Media-Converter don't accept packet little than 64 byte (802.3ab IANA Standard)

In normal condition, the port I want to monitor don't generate packet little than 64 byte but I can see 64 butes packet passing through GigaEthernet Span Destination Port. That's why I can't see all the traffic that leave from GE Span Port, arriving to “Monitor Server” Side.

Here is the question: doues anyone know how to modify the size of the packet leaving from a span destination port?

Thanx in adv for any help