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permit icmp
Configure a filter to allow all or specific ICMP messages.
Syntax
permit icmp {source mask | any | host ip-address} {destination mask | any |
host ip-address} [type] [dscp] [message-type] [count [byte] | log] [order]
[monitor] [fragments] [no-drop]
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 permit 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 /prefix format (/x) or A.B.C.D. The mask, when specified
in A.B.C.D format, may be either contiguous or noncontiguous.
any Enter the keyword any to match and drop specific Ethernet traffic on the
interface.
host ip-address Enter the keyword host and then enter 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.
type Enter the ICMP packet type. The following types are available:
For IPv4:
echo count
echo-reply count
host-unreachable count
host-unknown count
network-unknown count
net-unreachable count
packet-too-big count
parameter-problem count
port-unreachable count
source-quench count
time-exceeded count
For IPv6:
echo count
echo-reply count
nd-ns count
nd-na count
packet-too-big count
parameter-problem count
time-exceeded count
port-unreachable count
The ICMP packets cannot be filtered using mirroring ACL.
dscp
Enter the keyword dscp to deny a packet based on the DSCP value. The range is 0
to 63.
message-type (OPTIONAL) Enter an ICMP message type, either with the type (and code, if
necessary) numbers or with the name of the message type. The range is 0 to 255
for ICMP type and 0 to 255 for ICMP code.
count (OPTIONAL) Enter the keyword count to count packets the filter processes.
byte (OPTIONAL) Enter the keyword byte to count bytes the filter processes.
log (OPTIONAL, E-Series only) Enter the keyword log to have the information kept in
an ACL log file.
206 Access Control Lists (ACL)