Users Guide

deny icmp (for Extended IP ACLs)
To drop all or specic internet control message protocol (ICMP) messages, congure a lter.
NOTE: Only the options that have been newly introduced in Release 9.3(0.0) and Release 9.4(0.0) are described here.
For a complete description on all of the keywords and variables that are available with this command, refer the topic of
this command discussed earlier in this guide.
Syntax
deny icmp {source mask | any | host ip-address} {destination mask | any |
host ip-address} [dscp] [message-type] [count [byte]] [order] [fragments]
[log [interval minutes] [threshold-in-msgs [count]] [monitor]
To remove this lter, you have two choices:
• Use the no seq sequence-number command if you know the lter’s sequence number.
•
Use the no deny icmp {source mask | any | host ip-address} {destination
mask | any | host ip-address} command.
Parameters
log (OPTIONAL) Enter the keyword log to enable the triggering of ACL log messages.
threshold-in msgs
count
(OPTIONAL) Enter the threshold-in-msgs keyword followed by a value to
indicate the maximum number of ACL logs that can be generated, exceeding which
the generation of ACL logs is terminated with the seq, permit, or deny
commands. The threshold range is from 1 to 100.
interval minutes (OPTIONAL) Enter the keyword interval followed by the time period in minutes
at which ACL logs must be generated. The time interval range is from 1 to 10
minutes.
monitor (OPTIONAL) Enter the keyword monitor when the rule is describing the trac
that you want to monitor and the ACL in which you are creating the rule is applied
to the monitored interface.
Defaults By default, 10 ACL logs are generated if you do not specify the threshold explicitly.
The default frequency at which ACL logs are generated is ve minutes. By default, ow-based monitoring is
not enabled.
Command Modes CONFIGURATION-EXTENDED-ACCESS-LIST
Command History
Version 9.3(0.0) Added support for logging of ACLs on the S4810, S4820T, and Z9000 platforms.
Version 9.4(0.0) Added support for ow-based monitoring on the S4810, S4820T, S6000, and
Z9000 platforms.
Usage Information
When the congured maximum threshold is exceeded, generation of logs is stopped. When the interval at
which ACL logs are congured to be recorded expires, the subsequent, fresh interval timer is started and the
packet count for that new interval commences from zero. If ACL logging was stopped previously because
the congured threshold is exceeded, it is re-enabled for this new interval.
If ACL logging is stopped because the congured threshold is exceeded, it is re-enabled after the logging
interval period elapses. ACL logging is supported for standard and extended IPv4 ACLs, IPv6 ACLs, and
MAC ACLs. You can congure ACL logging only on ACLs that are applied to ingress interfaces; you cannot
enable logging for ACLs that are associated with egress interfaces.
You can activate ow-based monitoring for a monitoring session by entering the ow-based enable
command in the Monitor Session mode. When you enable this capability, trac with particular ows that are
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Access Control Lists (ACL)