This section describes the following mirroring configuration caveats:
Multiple mirroring service IDs (mirror destinations) may be created within a single system.
A mirrored source can only have one destination.
On the 7210 SAS-Dxp, before using a dot1q SAP or Q1.* SAP as a mirror destination, the user must configure a port for use with this feature using the config>system>loopback-no-svc-port mirror CLI command. The user has the option to use either one of the available virtual internal port resources or a front panel port. The available virtual internal port resources can be determined using the show>system>internal-loopback-ports detail CLI command. No services can be configured on this port. See the 7210 SAS-D, Dxp, K 2F1C2T, K 2F6C4T, K 3SFP+ 8C Interface Configuration Guide for more information about both commands.
On the 7210 SAS-D and 7210 SAS-Dxp, in case of port egress mirroring, one egress mirror source can be configured to only one mirror destination. In other words, with port egress mirroring multiple ports configured as mirror sources cannot use the same mirror destination.
On the 7210 SAS-D, the software uses the resources associated with an internal port for mirror application. The user does not need to explicitly configure it.
On the 7210 SAS-Dxp, the user can choose one of the three available loopback ports based on requirements. The three internal loopback ports (displayed using the show>system>internal-loopback-ports command) have different capacities; one port is 1GE capacity and two ports are 10GE capacity. When the user needs to mirror traffic to a dot1q SAP which exceeds 1GE but does not exceed 10GE, they must use a 10GE internal loopback port.
The destination mirroring service IDs and service parameters are persistent between router reboots and are included in the configuration saves.
Mirror source criteria configuration (defined in debug>mirror>mirror-source) is not preserved in a configuration save (admin save). Debug mirror source configuration can be saved using admin debug-save.
Physical layer problems such as collisions or jabbers are not mirrored. Typically, only complete packets are mirrored.
Starting and shutting down mirroring:
Mirror destinations:
The default state for a mirror destination service ID is shutdown. You must issue a no shutdown command to enable the feature.
When a mirror destination service ID is shut down, mirrored packets associated with the service ID are not accepted from its mirror source. The associated mirror source is put into an operationally down mode. Mirrored packets are not transmitted out the SAP. Each mirrored packet is silently discarded.
Issuing the shutdown command causes the mirror destination service or its mirror source to be put into an administratively down state. Mirror destination service IDs must be shut down first to delete a service ID or SAP association from the system.
Mirror sources:
The default state for a mirror source for a specific mirror-dest service ID is no shutdown. Enter a shutdown command to deactivate (disable) mirroring from that mirror-source.
Mirror sources do not need to be shut down to remove them from the system. When a mirror source is shut down, mirroring is terminated for all sources defined locally for the mirror destination service ID.