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The port mirroring application maintains a database that contains all monitoring sessions (including port monitor sessions). It
has information regarding the sessions that are enabled for flow-based monitoring and those sessions that are not enabled for
flow-based monitoring. It downloads monitoring configuration to the ACL agent whenever the ACL agent is registered with the
port mirroring application or when flow-based monitoring is enabled.
The show monitor session session-id command has been enhanced to display the Type field in the output, which
indicates whether a particular session is enabled for flow-monitoring.
Example Output of the show Command
#show running-config monitor session
!
monitor session 11
flow-based enable
source GigabitEthernet 13/0 destination GigabitEthernet 13/1 direction both
The show running-config monitor session command displays whether flow-based monitoring is enabled for a
particular session.
The show config command has been modified to display monitoring configuration in a particular session.
Example Output of the show Command
(conf-mon-sess-11)#show config
!
monitor session 11
flow-based enable
source GigabitEthernet 13/0 destination GigabitEthernet 13/1 direction both
The show ip | mac | ipv6 accounting commands have been enhanced to display whether monitoring is enabled for
traffic that matches with the rules of the specific ACL.
Example Output of the show Command
Dell# show ip accounting access-list
!
Extended Ingress IP access list kar on GigabitEthernet 10/0
Total cam count 1
seq 5 permit ip 192.168.20.0/24 173.168.20.0/24 monitor
Dell#show mac accounting access-list kar in gi 10/0 out
Egress Extended mac access-list kar on GigabitEthernet 10/0
seq 5 permit host 11:11:11:11:11:11 host 22:22:22:22:22:22 monitor
seq 10 permit host 22:22:22:22:22:22 any monitor
seq 15 permit host 00:0f:fe:1e:de:9b host 0a:0c:fb:1d:fc:aa monitor
Dell#show ipv6 accounting access-list
!
Ingress IPv6 access list kar on GigabitEthernet 10/0
Total cam count 1
seq 5 permit ipv6 22::/24 33::/24 monitor
Enabling Flow-Based Monitoring
Flow-based monitoring conserves bandwidth by monitoring only specified traffic instead of all traffic on the interface. This
feature is particularly useful when looking for malicious traffic. It is available for Layer 2 and Layer 3 ingress and egress traffic.
You can specify traffic using standard or extended access-lists.
1. Enable flow-based monitoring for a monitoring session.
MONITOR SESSION mode
flow-based enable
2. Define access-list rules that include the keyword monitor. Dell Networking OS only considers port monitoring traffic that
matches rules with the keyword monitor.
CONFIGURATION mode
ip access-list
For more information, see Access Control Lists (ACLs).
Access Control Lists (ACLs)
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