Cisco MWR 1941-DC - 1941 Mobile Wireless Router, Руководство по настройке программного обеспечения

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Cisco MWR 1941-DC Mobile Wireless Edge Router Software Configuration Guide
OL-11503-01
Chapter 6 Configuring the MWR 1941-DC in a Cell Site DCN
Filtering IP Packets Using Access Lists
Even if you use the ip access-list log-update command, the 5-minute timer remains in effect, so each
cache is emptied at the end of 5 minutes, regardless of the count of messages in each cache. Regardless
of when the log message is sent, the cache is flushed and the count reset to 0 for that message the same
way it is when a threshold is not specified.
Note
The logging facility might drop some logging message packets if there are too many to be handled
or if there is more than one logging message to be handled in 1 second. This behavior prevents the
router from crashing due to too many logging packets. Therefore, the logging facility should not be
used as a billing tool or an accurate source of the number of matches to an access list.
Note
If you enable CEF and then create an access list that uses the log keyword, the packets that match the
access list are not CEF switched. They are fast switched. Logging disables CEF.
For an example of a standard IP access list using logs, see the “Numbered Access List Examples” section
on page 6-60 .