Administrator Guide

When you use the log option, the CP processor logs detail the packets that match. Depending on how
many packets match the log entry and at what rate, the CP may become busy as it has to log these
packets’ details.
Use the monitor option only when you are using flow-based monitoring. For more information, refer to
the Port Monitoring chapter of the C9000 Series Configuration Guide.
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 five minutes. By default, flow-based monitoring is not enabled.
Related
Commands
deny tcp — assigns a filter to deny TCP packets.
deny udp — assigns a filter to deny UDP packets.
ip access-list extended — creates an extended ACL.
deny icmp
To drop all or specific internet control message protocol (ICMP) messages, configure a filter.
C9000 Series
Syntax
deny icmp {source–ip—address mask | any | host ip-address} {destination
mask | any | host ip-address} [log] [dscp] [[count [bytes]] [order]
[monitor] [fragments]
To remove this filter, you have two choices:
● Use the no seq sequence-number command if you know the filter’s sequence number.
● Use the no deny icmp {source–ip—address mask | any | host ip-address}
{destination mask | any | host ip-address} command.
Parameters
source-ip-
address
Enter the IP address of the network or host from which the packets were sent.
mask Enter a network mask in /prefix format (/x) or A.B.C.D. The mask, when specified
in A.B.C.D format, may be either contiguous or non-contiguous.
any Enter the keyword any to specify that all routes are subject to the filter.
host ip-address Enter the keyword host then the IP address to specify a host IP address.
destination Enter the IP address of the network or host to which the packets are sent.
log (OPTIONAL) Enter the keyword log to include ACL matches in the log.
dscp Enter this keyword dscp to deny a packet based on the DSCP value. The range is
from 0 to 63.
count (OPTIONAL) Enter the keyword count to count packets processed by the filter.
bytes (OPTIONAL) Enter the keyword bytes to count bytes processed by the filter.
order (OPTIONAL) Enter the keyword order to specify the QoS priority for the ACL
entry. The range is from 0 to 254 (where 0 is the highest priority and 254 is the
lowest; lower order numbers have a higher priority) If you did not use the keyword
order, the ACLs have the lowest order by default (255).
monitor (OPTIONAL) Enter the keyword monitor when the rule is describing the traffic
that you want to monitor and the ACL in which you are creating the rule is applied
to the monitored interface. For more information, refer to the “Flow-based
Monitoring” section in the Port Monitoring chapter of the Dell Networking OS
Configuration Guide.
fragments Enter the keyword fragments to use ACLs to control packet fragments.
Defaults Not configured.
236 Access Control Lists (ACL)