Administrator Guide
monitoring only specified traffic instead all traffic on the interface. This feature is particularly useful when
looking for malicious traffic. It is available for Layer 2 and Layer 3 ingress and egress traffic. You may
specify traffic using standard or extended access-lists. This mechanism copies all incoming or outgoing
packets on one port and forwards (mirrors) them to another port. The source port is the monitored port
(MD) and the destination port is the monitoring port (MG).
Related
Commands
● deny — configure a filter to drop packets.
● permit — configure a filter to forward packets.
seq (for IPv6 ACLs)
Assign a sequence number to a deny or permit the filter in an IPv6 access list while creating the filter.
Syntax
seq sequence-number {deny | permit} {ipv6-protocol-number | icmp | ip | tcp
| udp} {source address mask | any | host ipv6-address} {destination address
| any | host ipv6-address} [operator port [portnumber ]] [count [byte]]
[log [interval minutes] [threshold-in-msgs [count]] [monitor]
To delete a filter, use the no seq sequence-number command.
Parameters
sequence-
number
Enter a number from 0 to 4294967290.
deny Enter the keyword deny to configure a filter to drop packets meeting this
condition.
permit Enter the keyword permit to configure a filter to forward packets meeting this
criteria.
ipv6-protocol-
number
Enter a number to filter based on the protocol identified in the IPv6 protocol
header.
icmp Enter the keyword icmp to configure an ICMP access list filter.
ip Enter the keyword ip to configure a generic IP access list. The keyword ip
specifies that the access list permits all IP protocols.
tcp Enter the keyword tcp to configure a TCP access list filter.
udp Enter the keyword udp to configure a UDP access list filter.
source
Enter an IP address in dotted decimal format of the network from which the packet
was received.
mask
(OPTIONAL) Enter a network mask in /prefix format (/x) .
any Enter the keyword any to specify that all routes are subject to the filter.
host
ipv6-
address
Enter the keyword host and then enter the IPv6 address to specify a host IP
address or hostname.
operator
(OPTIONAL) Enter one of the following logical operands:
● eq = equal to
● neq = not equal to
● gt = greater than
● lt = less than
● range = inclusive range of ports (you must specify two ports for the port
parameter.)
portnumber
(OPTIONAL) Enter the application layer port number. Enter two port numbers if
you are using the range logical operand. The range is from 0 to 65535.
The following list includes some common TCP port numbers:
● 23 = Telnet
Access Control Lists (ACL) 299