About Selecting Inbound Traffic Using Advanced Classifier-Based Mirroring - HP Aruba JL253A Management And Configuration Manual

• Up to 320 different MAC addresses are supported for traffic selection in all mirroring sessions configured on
the switch.
• A destination MAC address is not supported as mirroring criteria for routed traffic, because in routed packets,
the destination MAC address is changed to the next-hop address when the packet is forwarded. Therefore, the
destination MAC address that you want to mirror will not appear in routed packet headers.
This restriction also applies to the destination MAC address of a host that is directly connected to a routing
switch. (Normally, a host is connected to an edge switch, which is directly connected to the router.)
To mirror routed traffic, we recommend that you use classifier-based policies to select IPv4 or IPv6 traffic for
mirroring, as described in.
• On a switch, you can use a MAC address only once as a source MAC address and only once as a destination
MAC address to filter mirrored traffic.
For example, after you enter the following commands:
monitor mac 111111-222222 src mirror 1
monitor mac 111111-222222 dest mirror 2
The following commands are not supported:
monitor mac 111111-222222 src mirror 3
monitor mac 111111-222222 dest mirror 4
In addition, if you enter the monitor mac 111111-222222 both mirror 1 command, you cannot use
the MAC address 111111-222222 in any other monitor mac mirror configuration commands on the
switch.
• To re-use a MAC address that has already been configured as a source and/or destination address for traffic
selection in a mirror session, you must first remove the configuration by entering the no form of the command
and then re-enter the MAC address in a new monitor mac mirror command.
For example, if you have already configured MAC address 111111-222222 to filter inbound and outbound
mirrored traffic, and you decide to use it to filter only inbound traffic in a mirror session, you could enter the
following commands:
monitor mac 111111-222222 both mirror 1
no monitor mac 111111-222222 both mirror 1
monitor mac 111111-222222 src mirror 1
• A mirroring session in which you configure MAC-based mirroring is not supported on a port, trunk, mesh, or
VLAN interface on which a mirroring session with a classifier-based mirroring policy is configured.

About selecting inbound traffic using advanced classifier-based mirroring

In addition to the traffic selection options, traffic mirroring supports the use of advanced classifier-based functions
that provide:
• A finer granularity for selecting the inbound IP traffic that you want to mirror on an individual port or VLAN
interface (instead of mirroring all inbound traffic on the interface)
• Support for mirroring both IPv4 and IPv6 traffic
• The ability to re-use the same traffic classes in different software-feature configurations; for example, you can
apply both a QoS rate-limiting and mirroring policy on the same class of traffic.
Chapter 12 Monitoring and Analyzing Switch Operation 435