Dennis Hilberg Jr wrote: > Hello. > > I am new to ntpd, and have a question regarding the ntp.conf. > > First of all, here is my ntp.conf: > > > restrict 127.0.0.1 > > server bigben.cac.washington.edu iburst > server time-nw.nist.gov iburst > server usno.pa-x.dec.com iburst > server nist1.aol-ca.truetime.com iburst > server clepsydra.dec.com iburst > > driftfile /etc/ntp/drift > logfile /var/log/ntp.log > > > Is this an acceptable ntp.conf for running a public ntp server? I'm > considering submitting my server to the pool, but only if I know it's > relatively secure. I'm having a hard time finding ntp.conf examples for > public ntp servers with descriptions of each setting. I've followed > whatever advice I've found: no more than five servers, no local server, etc. > I use my ntp server for syncing time on my local network, and it works > great. > > Basically, do I need any other security settings to run a secure > (relatively) public ntp server? Or am I good to go to open up the firewall? > > Thanks for any assistance! > > Dennis > >
It should work. I think you might want to create an ntp.keys file and add a pointer to it to your ntp.conf # # Authentication parameters # keys /etc/inet/ntp.keys trustedkey 2 3 4 controlkey 3 # To access the ntpq utility requestkey 2 # To access the ntpdc utility In addition, you should probably have some restrict statements: restrict default nomodify noquery notrust restrict 127.0.0.1 # Allow free access to localhost restrict 192.168.1.0 mask 255.255.255.0 # Allow my local network restrict <server IP> nomodify # For each server And: # # NTP monitoring parameters # statsdir /var/ntp/ntpstats/ statistics loopstats peerstats clockstats filegen loopstats file loopstats type day enable filegen peerstats file peerstats type day enable filegen clockstats file clockstats type day enable Last, but not least, you might want to set up authentication with the servers you are using. This guarantees that the servers you get time from are, in fact, the servers you think they are; e.g. nobody can deceive you by pretending to be a well known public server. I see that your address is comcast.net. Did you get a static IP address from them or are you using Dyndns? If your address changes every few weeks, as Comcast tends to do, it will make it difficult for your clients to keep up with you. Do you have an uninterruptable power system (UPS) for your server and network components? _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
