Users 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.
The monitor option is relevant in the context of ow-based monitoring only. For more information, see Port
Monitoring
.
The C-Series and S-Series cannot count both packets and bytes, when you enter the count byte options, only
bytes are incremented.
NOTE: When you congure ACL logging and byte counters simultaneously, byte counters may display
an incorrect value. Congure packet counters with logging instead.
Related Commands
• deny tcp — assign a lter to deny TCP packets.
• deny udp — assign a lter to deny UDP packets.
• ip access-list extended — create an extended ACL.
deny icmp
To drop all or specic internet control message protocol (ICMP) messages, congure a lter.
Syntax
deny icmp {source mask | any | host ip-address} {destination mask | any | host
ip-address} [dscp] [count [byte] [order] [fragments] [no-drop]
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
source Enter the IP address of the network or host from which the packets were sent.
mask Enter a network mask in /prex format (/x) or A.B.C.D. The mask, when specied 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 lter.
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.
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 lter.
byte (OPTIONAL) Enter the keyword byte to count bytes processed by the lter.
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).
fragments Enter the keyword fragments to use ACLs to control packet fragments.
no-drop Enter the keywords no-drop to match only the forwarded packets.
Defaults Not congured.
Access Control Lists (ACL) 193