traversing through the ingress and egress interfaces are examined and, appropriate ACLs can be applied in both
the ingress and egress direction. Flow-based monitoring conserves bandwidth by 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).
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
|
portname
]] [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.
Access Control Lists (ACL)
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