Mirror vlan tag

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  • Updated 3 years ago
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I've checked using Wireshark.scenario.

Sw1
-vlan 10 192.168.10.1/24 tag 10
-vlan 20 192.168.20.1/24 tag 20
-vlan 30 192.168.30.1/24 tag 30

   ===== Trunk ======
Sw2
-vlan 10 192.168.10.2/24 tag 10
-vlan 20 192.168.20.2/24 tag 20
-vlan 30 192.168.30.2/24 tag 30


I sent ping. Switch 1 -> Switch 2

Switch1 had confirmed.

ICMP Request message contains an 802.1Q field.
ICMP Reply message not include an 802.1Q filed.

Switch2

ICMP Reply message contains an 802.1Q filed.
ICMP Request message not include an 802.1Q field.

When the switch is copied to the mirror port do?

Ingress traffic are decapsulation and then copy?

egress traffic are capsulation and then copy?

Is it because this process?

vlan-id will be attached when traffic pass through the output port.

vlan-id will be reomve when traffic input through the input port.

So that I can not be verified to about ingree packet ?  

How do I check without Wireshark?
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Dong

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Posted 3 years ago

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OscarK, ESE

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Hello,

normally the packet should egress the mirror port as it would egress a normal port, if the mirrored packet is untagged it will exit the mirror port also as untagged.  CPU generated traffic (like a ping reply from the switch itself) could be copied to the mirror port as untagged depending on HW and version. Check the user guide for guidelines, rules and restrictions on mirroring in the configuring ports section.