Thank for prompt answer Chris, Unfortunately, this ntp network should give time to specific clients devices and not anyone on the public network.
according to your advice, better not using load balancer, thats good how to load balance between ntp server if i do not use round robin? if all client choosing the same server then the ntp server will be overload. is it a problem if for example client 1 poll or synch with server 1 , and then with server 2 , etc...? or udp roundtrip comes each time from different ntp server? how many ntp servers should be needed to handle that much request knowing that each card handle 10,000 request per sec? much appreciate your expertize cheers > From: [email protected] > Date: Wed, 21 Dec 2011 19:43:53 -0800 > Subject: Re: [ntp:questions] ntp server pool advice > To: [email protected] > > On Wed, Dec 21, 2011 at 5:07 PM, ben slimup <[email protected]> wrote: > > > > Dear all, > > > > Thank you very much for support, > > > > i do not have 1000,000 client, i need those ntp servers to serve a load > > between 100000 to 1000000 clients > > over a public network with an accuracy of 100ms > > > > those clients will use dns round robin to resolve 4 external ip, 2 IPs on > > each site. > > i have 4 servers with 4 ntp server slot card each ( meinberg M900) > > 1 ntp server card can support 10,000 request. > > First off the good news. 100ms is an "easy" spec to meet you can do > this without a lot of effort. > > Don't let the outside world "see" your meinberg servers. Build out > a layer of "statum 2" servers and expose those to your clients. 1M > clients is a lot for the little 386 class CPU that is in the meinberg > box. > > I still don't understand, Why do all those NTP clients need to go to > your NTP servers. Why can't they use any they like? Are your > servers doing something special? > > Also know that EACH client needs to be configured to see multiple NTP > servers. practically three servers is a minimum but others will argue > for more for five > > A would not use load balancing for NTP servers. With NTP it does > not matter at all if a server crashes. The clients are all configure > to use five servers and if one crashes they will do fine using four. > If you expose four, large robust servers one on each of your four IP > addresses then you will be fine, even if one fails you will be fine. > The clients will notice the failure and continue on using the > remaining three. > > > I technical question for the list: Would Round Robin load balancing > even work. I think it would introduce so much jitter the server would > be usless. I think you have to be sure that each time a client pools > a server at a given IP address it polls the same physical server. > > Chris Albertson > Redondo Beach, California _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
