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Dell(conf-mon-sess-2)#source tengig 0/1 destination tengig 0/9 direction both
% Error: MD port is already being monitored.
NOTE: There is no limit to the number of monitoring sessions per system, provided that there are only four destination
ports per port-pipe. If each monitoring session has a unique destination port, the maximum number of session is four per
port-pipe.
Port Monitoring
The Aggregator supports multiple source-destination statements in a monitor session, but there may only be one destination
port in a monitoring session.
There may only be one destination port in a monitoring session (% Error: Only one MG port is allowed in a
session.).
The number of source ports the Dell Networking OS allows within a port-pipe is equal to the number of physical ports in the
port-pipe (n). Multiple source ports may have up to four different destination ports (Exceeding max MG ports for this
MD port pipe.).
In the following examples, ports 0/1, 0/2, 0/3, and 0/4 all belong to the same port-pipe. These ports mirror traffic to four
different destinations (0/9, 0/10, 0/11, and 0/12).
Example of Number of Monitoring Ports
Dell#show mon session
SessionID Source Destination Direction Mode Type
--------- ------ ----------- --------- ---- ----
0 TenGig 0/1 TenGig 0/9 rx interface Port-based
10 TenGig 0/2 TenGig 0/10 rx interface Port-based
20 TenGig 0/3 TenGig 0/11 rx interface Port-based
30 TenGig 0/4 TenGig 0/12 rx interface Port-based
Dell(conf)#
A source port may only be monitored by one destination port, but a destination port may monitor more than one source port.
Dell Networking OS Behavior: All monitored frames are tagged if the configured monitoring direction is transmit (TX),
regardless of whether the monitored port (MD) is a Layer 2 or Layer 3 port.
● If the MD port is a Layer 2 port, the frames are tagged with the VLAN ID of the VLAN to which the MD belongs.
● If the MD port is a Layer 3 port, the frames are tagged with VLAN ID 4095.
● If the MD port is in a Layer 3 VLAN, the frames are tagged with the respective Layer 3 VLAN ID.
For example, in the configuration source tengig 0/1 destination tengig 0/9 direction tx, if the source port
0/1 is an untagged member of any VLAN, all monitored frames that the destination port 0/9 receives are tagged with the VLAN
ID of the source port.
Remote Port Mirroring
Remote Port Mirroring is supported on the FN IOM Switch platform.
While local port monitoring allows you to monitor traffic from one or more source ports by directing it to a destination port on
the same switch/router, remote port mirroring allows you to monitor Layer 2 and Layer 3 ingress or egress or both ingressing
or egressing traffic on multiple source ports on different switches and forward the mirrored traffic to multiple destination ports
on different switches. Remote port mirroring helps network administrators monitor and analyze traffic to troubleshoot network
problems in a time-saving and efficient way.
In a remote-port mirroring session, monitored traffic is tagged with a VLAN ID and switched on a user-defined, non-routable
L2 VLAN. The VLAN is reserved in the network to carry only mirrored traffic, which is forwarded on all egress ports of the
VLAN. Each intermediate switch that participates in the transport of mirrored traffic must be configured with the reserved L2
VLAN. Remote port monitoring supports mirroring sessions in which multiple source and destination ports are distributed across
multiple switches
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Port Monitoring