On 7/18/2010 7:00 PM, Danny Mayer wrote: > On 7/15/2010 6:37 PM, E-Mail Sent to this address will be added to the > BlackLists wrote: >> Rob wrote: >>> hymie! wrote: >>>> My servers are configured to use >>>> server 0.us.pool.ntp.org >>>> server 1.us.pool.ntp.org >>>> server 2.us.pool.ntp.org >>>> server 3.us.pool.ntp.org >>>> >>>> Through what I presume is a fluke of the DNS randomization, three of >>>> my four hosts were: >>>> 153.16.4.139 .INIT. 16 u 390 512 0 0.000 0.000 4000.00 >>>> 153.16.4.133 .INIT. 16 u 378 512 0 0.000 0.000 4000.00 >>>> 153.16.4.140 .INIT. 16 u 384 512 0 0.000 0.000 4000.00 >>>> >>>> I tried searching the NTP web sites to figure out who >>>> maintains the NTP pools, and this was the best lead I got. >>>> If these hosts are no longer offerring NTP, can they >>>> (and perhaps others in that same net block) be removed >>>> from the pool? >> >> Pool servers are babysat and removed automatically. >> <http://www.pool.ntp.org/en/scores> >> >>> Hosts that are not offering NTP are automatically removed from the pool. >>> Unfortunately, with (commonly used versions of) ntpd this DNS lookup >>> is only done when it is started. So when you get 4 working NTP servers, >>> it may well happen that they stop offering NTP service later and you get >>> the above result. >>> It can be fixed by restarting ntpd. >> >> Isn't this greatly improved in NTP 4.2.7p22 and later? >> {When using the pool server option} >> >> Aren't the pool servers tossed after 10 polls without >> surviving clock selection and then NTP will get IPs for >> more pool servers? >> > > Not yet. That work is under way but it takes a lot of infrastructure > work to do that.
A discussion with Dave Hart indicates that in p22 and later for the pool only the it works like a manycastclient and adds and removes servers using the IP addresses that it received. I don't know if it refetches a new DNS list but that's certainly on my agenda. Danny > Danny > >> e.g. >> >> tos minclock 6 minsane 4 cohort 1 >> >> peer myNTPserverClock.example.org iburst >> server myNTPserverDyn.example.org iburst preempt >> server myISPsNTPserver1.example.com iburst >> server myISPsNTPserver2.example.com iburst >> server myUpStreamsNTPserverA.example.net iburst >> server myUpStreamsNTPserverB.example.net iburst >> >> pool 0.us.pool.ntp.org iburst >> pool 1.us.pool.ntp.org iburst >> pool 2.us.pool.ntp.org iburst >> pool 3.us.pool.ntp.org iburst >> > > _______________________________________________ > questions mailing list > [email protected] > http://lists.ntp.org/listinfo/questions > > _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
