[ntp:questions] Max number of lines that ntpdc -c monlist could display

Danny Mayer mayer at ntp.isc.org
Wed May 9 12:01:09 UTC 2007

mills at udel.edu wrote:
> Danny,
> The max packet size used by ntpd in response to a request is 468 data 
> bytes plus headers. The problem is not the packet size, but the number 
> of packets. Even with the default max lines, this can result in a burst 
> up to 80 packets. While modern gatways and routers can usully handle 
> such a burst, it might set off flood alarms in the firewalls.
> Dave

Well we can increase the packet size fairly easily just like BIND has
done, but having larger packets would have other impacts which would
have to be explored. Switching to TCP would be a better solution as you
had indicated earlier. Even having it in ntpq would be better.


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