Port Mirroring with Greenspan

The mirroring features allow the mirroring of source port packets for sending and receiving on a local destination port. Mirroring with the Greenspan feature allows the mirroring of source packets in the receiving direction onto the GRE tunnel.

Configuring Mirroring with Greenspan and Port

These commands configure a mirroring session with a destination for the GRE tunnel interface and regular port.

Syntax

Source Port 

router(config)# monitor session name source interface [ rx | tx |both ] [ ip access-group access-list-name

 

GREENSPAN Destination 

router(config)# monitor session name destination tunnel mode gre source ipAddress destination ipAddress ttl ttlValue dscp
dscpValue

 

Port Destination

router(config)# monitor session name destination interface

 

Example: 

router(config)# monitor session r1 source Ethernet2 rx ip access-group a3
router(config)# monitor session r1 destination tunnel mode gre source 75.75.75.75 destination 100.1.0.2

 

Displaying Mirroring with Greenspan and Port Information

These two commands display the monitor and platform-related mirroring information.
  • show monitor session
  • show platform sfe mirroring

Examples:

The show monitor session command displays the session information. 
router# show monitor session

Session r1
------------------------

Programmed in HW: Yes

Source Ports:

  Rx Only:     Et2(IPv4 ACL: a3)

Destination Ports:

          status    source       dest           TTL  DSCP     proto    VRF fwd-drop
  Gre1 :  active    5.75.75.75   100.1.0.2 128  0    0x88be   default   no
      next hop interfaces: Et5

 

The show platform sfe mirroring command displays the platform-specific SFE mirroring information. 
router# show platform sfe mirroring
Session: r1, mirrorGroup: 3, globalId: 0
 srcIntf: Ethernet2, direction: Rx
 tgtIntf: Gre1
  encapType: Gre
 Sfe module: Mir_r1_Rx_et2
  Sfe srcIntf: Ethernet2, direction: Rx, gate: 0
  Sfe tgtIntf: Ethernet5, gate: 1
  Copy Success: 47523752, Fail: 0
  Forward Success: 53109025, Fail: 0