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The Dell EMC Networking OS honors any permit or deny actions of the ACL rules used for ow-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
dierent 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 trac 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 trac 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 congure the flow-based enable command and do not apply an ACL on the source port or the monitored port, both ow-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 ow-based monitoring and those sessions that are not enabled for ow-based
monitoring. It downloads monitoring conguration to the ACL agent whenever the ACL agent is registered with the port mirroring
application or when ow-based monitoring is enabled.
The show monitor session session-id command displays the Type eld in the output, which indicates whether a particular
session is enabled for ow-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 1/2/1 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 modied to display monitoring conguration in a particular session.
Example Output of the show Command
(conf-mon-sess-11)#show config
!
monitor session 11
flow-based enable
source twentyFiveGigE 1/1 destination twentyFiveGigE 1/1 direction both
The show ip accounting commands have been enhanced to display whether monitoring is enabled for trac that matches with the
rules of the specic ACL.
Access Control Lists (ACLs)
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