nanog mailing list archives
Re: Fwd: port 123 reflection attacks
From: Randy Bush <randy () psg com>
Date: Thu, 31 Dec 2015 11:16:07 +0900
- be sure ntpd is properly configured
to be explicit, test it
% ntpdc -n -c monlist psg.com
psg.com: timed out, nothing received
***Request timed out
this is the desired result. any real response means the host is open
to be a reflector
fwiw, i got caught last week. a debien vm had been brought up using
dhcp, and the /var/lib/ntp/ntp.conf.dhcp was still there after the host
was reconfigured to static. took me a while to find it. embarrassing.
my ntp.yml playbook now has as it's first task
- name: remove dhcpd artifact
file: path=/var/lib/ntp/ntp.conf.dhcp state=absent
randy
Current thread:
- Fwd: port 123 reflection attacks Colin Johnston (Dec 30)
- Re: Fwd: port 123 reflection attacks alvin nanog (Dec 30)
- Re: Fwd: port 123 reflection attacks Randy Bush (Dec 30)
- Re: Fwd: port 123 reflection attacks alvin nanog (Dec 30)
