Mirroring

Port mirroring selects the network traffic for analysis by a network analyzer. This is done for specific ports of the switch. As such, many switch ports are configured as source ports and one switch port is configured as a destination port. You can configure how traffic is mirrored on a source port. Packets that are received on the source port, that are transmitted on a port, or are both received and transmitted, can be mirrored to the destination port.

The packet that is copied to the destination port is in the same format as the original packet on the wire. This means that if the mirror is copying a received packet, the copied packet is VLAN tagged or untagged as it was received on the source port. If the mirror is copying a transmitted packet, the copied packet is VLAN tagged or untagged as it is being transmitted on the source port.

Use the Multiple Port Mirroring page to define port mirroring sessions.

To access this page, click System > Port > Mirroring in the navigation menu.

Use the buttons to perform the following tasks:

  • To configure the administrative mode for a port mirroring session, click Configure Session and configure the desired settings.
  • To configure destination as Remote VLAN or probe port, click Edit and configure the desired settings.
  • To configure source as Remote VLAN or VLAN or one or more source ports for the mirroring session and to determine which traffic is mirrored (Tx, Rx, or both), click Configure Source and configure the desired settings.
  • To remove one or more source ports from the port mirroring session, select the checkbox for each source port to remove and click Remove Source.
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Multiple Port Mirroring Fields

Field Description
Session ID The port mirroring session ID. The number of sessions allowed is platform specific.
Mode The administrative mode for the selected port mirroring session. If the mode is disabled, the configured source is not mirroring traffic to the destination.
Destination
  • Remote VLAN: At the source switch the destination can be configured as RSPAN VLAN with reflector-port. The reflector-port forwards the mirrored traffic towards the destination switch. This port has to be configured with RSPAN VLAN membership.
  • Interface: If port configured as a interface or probe port. This port receives traffic from all configured source ports.
  • None: The destination is not configured.
IP ACL The IP access-list ID or name attached to the port mirroring session.
MAC ACL The MAC access-list name attached to the port mirroring session.
Source The ports or VLAN configured to mirror traffic to the destination. You can configure multiple source ports or one source VLAN per session. The source VLAN can also be a remote VLAN.
Direction The direction of traffic on the source port(s) that is sent to the probe port. Possible values are:
  • Tx and Rx: Both ingress and egress traffic.
  • Rx: Ingress traffic only.
  • Tx: Egress traffic only.