Service Manual

count for that new interval commences from zero. If ACL logging was stopped previously because the configured
threshold is exceeded, it is re-enabled for this new interval.
If ACL logging is stopped because the configured threshold is exceeded, it is re-enabled after the logging interval
period elapses. ACL logging is supported for standard and extended IPv4 ACLs, IPv6 ACLs, and MAC ACLs. You
can configure ACL logging only on ACLs that are applied to ingress interfaces; you cannot enable logging for ACLs
that are associated with egress interfaces.
You can activate flow-based monitoring for a monitoring session by entering the flow-based enable
command in the Monitor Session mode. When you enable this capability, traffic with particular flows that are
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).
Related Commands
deny — Configures a filter to drop packets.
permit — Configures a filter to forward packets.
permit udp
Configure a filter to pass UDP packets meeting the filter criteria.
Syntax
permit udp {source address mask | any | host ipv6-address} [operator port
[port]] {destination address | any | host ipv6-address} [operator port [port]]
[count [byte]] [log [interval minutes] [threshold-in-msgs [count]][monitor]
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 udp {source address mask | any | host ipv6-address}
{destination address | any | host ipv6-address} command.
Parameters
source address Enter the IPv6 address of the network or host from which the packets were sent in the
x:x:x:x::x format followed by the prefix length in the /x format. The range is /0 to /128.
The :: notation specifies successive hexadecimal fields of zero.
mask 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 followed by the IPv6 address of the host in the x:x:x:x::x format.
The :: notation specifies successive hexadecimal fields of zero.
operator (OPTIONAL) Enter one of the following logical operand:
• eq = equal to
• neq = not equal to
• gt = greater than
• lt = less than
• range = inclusive range of ports (you must specify two port for the port parameter.)
Access Control Lists (ACL) 241