Administrator Guide

Version Description
9.3(0.0) Added support for logging of ACLs on the S4810, S4820T, and Z9000 platforms.
Usage Information
When the congured maximum threshold is exceeded, generation of logs is stopped. When the interval at which
ACL logs are congured to be recorded expires, the subsequent, fresh interval timer is started and the packet
count for that new interval commences from zero. If ACL logging was stopped previously because the congured
threshold is exceeded, it is re-enabled for this new interval.
If ACL logging is stopped because the congured 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 congure 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 ow-based monitoring for a monitoring session by entering theflow-based enable command
in the Monitor Session mode. When you enable this capability, trac with particular ows 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 specied trac instead all
trac on the interface. This feature is particularly useful when looking for malicious trac. It is available for Layer 2
and Layer 3 ingress and egress trac. You may specify trac 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).
permit udp (for Extended IP ACLs)
To pass UDP packets meeting the lter criteria, congure a lter.
Syntax
permit udp {source mask | any | host ip-address} [operator port [port]]
{destination mask | any | host ip-address} [ttl operator] [dscp] [operator port
[port]] [count [byte]] [order] [fragments] [log [interval minutes] [threshold-
in-msgs [count]][monitor]
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 permit udp {source mask | any | host ip-address} {destination mask |
any | host ip-address command.
Parameters
ttl Enter the keyword ttl to permit a packet based on the time to live value. The range is
from 1 to 255.
operator Enter one of the following logical operand:
• eq(equal to) — matches packets that contain a ttl value that is equal to the specied
ttl value.
• neq(not equal to) — matches packets that contain a ttl value that is not equal to the
specied ttl value.
•
gt(greater than) — matches packets that contain a ttl value that is greater than the
specied ttl value.
• lt (less than) — matches packets that contain a ttl value that is less than the
specied ttl value.
• range(inclusive range of values) — matches packets that contain a ttl value that
falls between the specied range of ttl values.
Access Control Lists (ACL) 293