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When you apply an ACL within the monitor session, it is applied to all source interfaces configured in the monitor session.
The Dell EMC Networking OS honors any permit or deny actions of the ACL rules used for flow-based mirroring. Packets that
match a mirror ACL rule is denied or forwarded depending on the rule but the packet is mirrored. However, the user ACL has
precedence over the mirror ACL.
The same source interface can be part of multiple monitor sessions.
Flow-based monitoring is supported for SPAN, RSPAN, and ERSPAN sessions. If there are overlapping rules between ACLs
applied on different monitor sessions, the session with the highest monitor session ID takes precedence.
NOTE: You can apply only IPv4 ACL rules under monitor session context.
You must specify the monitor option with the permit, deny, or seq command for ACLs that are assigned to the source
or the monitored port (MD) to enable the evaluation and replication of traffic that is traversing to the destination port. Enter
the keyword monitor with the seq, permit, or deny command for the ACL rules to allow or drop IPv4, IPv6, ARP, UDP,
EtherType, ICMP, and TCP packets. The ACL rule describes the traffic that you want to monitor, and the ACL in which you
are creating the rule is applied to the monitored interface. Flow monitoring is supported for standard and extended IPv4 ACLs,
standard and extended IPv6 ACLs, and standard and extended MAC ACLs.
CONFIG-STD-NACL mode
seq sequence-number {deny | permit} {source [mask] | any | host ip-address} [count [byte]]
[order] [fragments] [log [threshold-in-msgs count]] [monitor]
If you configure the flow-based enable command and do not apply an ACL on the source port or the monitored port, both
flow-based monitoring and port mirroring do not function.
You cannot apply the same ACL to an interface or a monitoring session context simultaneously.
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 displays the Type field in the output, which indicates whether a
particular session is enabled for flow-monitoring.
Example Output of the show Command
DellEMC# show monitor session 1
SessID Source Destination Dir Mode Source IP Dest IP
DSCP TTL Drop Rate Gre-Protocol FcMonitor
------ ------ ----------- --- ---- --------- --------
---- --- ---- ---- ----------- ---------
1 Te 1/2 remote-ip rx Port 0.0.0.0 0.0.0.0 0
0 No N/A N/A yes
DellEMC#
The show config command has been modified to display monitoring configuration in a particular session.
Example Output of the show Command
The show ip 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
DellEMC# show ip accounting access-list
!
Extended Ingress IP access list kar on TenGigabitEthernet 1/1
Total cam count 1
seq 5 permit ip 192.168.20.0/24 173.168.20.0/24 monitor
DellEMC#show ipv6 accounting access-list
!
Ingress IPv6 access list kar on TenGigabitEthernet 1/1
Total cam count 1
seq 5 permit ipv6 22::/24 33::/24 monitor
Access Control Lists (ACLs)
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