What is port monitoring and how do I do it?
Product and Software: This article applies to all Aruba controllers and ArubaOS versions.
As you can with many network switches, you can copy packets from one Aruba Ethernet port to another. (Sometimes this is called a span port). This is useful for checking data that is coming into/out of the Aruba switch from the rest of the network. You can also copy AP input/output, if an AP is connected to an Ethernet port.
Port Monitoring Example
In this example, we want to copy traffic FROM port 5 TO port 13. The "show port monitor" command can be used to check status:
(Aruba2400) (config) #interface fastethernet 1/13
(Aruba2400) (config-if)#port monitor ?
fastethernet FastEthernet IEEE 802.3
gigabitethernet Gigabitethernet Interface
(Aruba2400) (config-if)#port monitor fastethernet 1/5
(Aruba2400) #show port monitor
Monitor Port Port being Monitored
fastethernet 1/13 fastethernet 1/5
After the monitor is started, you can connect your laptop/PC to port 13 and start an Ethereal session, in this case simply capturing from your Ethernet card. Use PCAP as usual.
When you have finished packet capturing, remember to switch off the port monitoring by issuing the following commands:
(Aruba2400) (config) #interface fastethernet 1/5
(Aruba2400) (config-if)#no port monitor fastethernet 1/13