Re: [ntp:questions] Dimensioning NTP Server
"Aggarwal Vivek-Q4997C" <[EMAIL PROTECTED]> escribió en el mensaje news:[EMAIL PROTECTED] > Hi > Iam planning to have NTP Server for something around 50,000 Clients in > the Network If you are being to deploy NTP to 50,000 clients, perhaps you'd better to put your routers (sure you don't have only one) or your DHCP servers to proxy NTP for them. You don't have to use just one NTP server, you can get several in synch so time is distributed with not so much network load. In doing so you'll get several advantages: * You'll get less network load, as NTP traffic don't pass over the local net. NTP is very sensible to network load. Time offsets get greater in loaded network. NTP proxies can use their clocks to stabilize time offsets due to network load. * You'll get less synch delay. People tends to think that using only one server will get all clients synched with it, but you'll get a couple of 50,000 pcs with different times, because of network load at time servers. NTP gets better results in a low loaded net. Time exactitude depends on two factors: network load introduces noise in time measurements, leading to greater time offsets from the source of time. Network NTP hops introduces a constant (or nearly constant) latency from the source of time, but this latencies are taken into account when synchronizing and you'll have better results using more levels of deploying time than making everything point to a master server. * You'll get more exact times if you balance the levels of stratumness with the number of clients that will ask a single server. I think a good starting balance is making all routers take time from your master server (better two or three servers for all the routers to get fault tolerance) and then the final clients to ask the routers for time. If you are considering to join 50,000 network nodes in a network, you'll be able to select routers capable of acting as timeservers for the localnet. > > Can Anyone guide me in dimensioning the NTP Server. What are the > guidelines that I should take care for dimensioning the NTP Server > > Also can I two NTP Servers running in active-stand by or in Load > balancing scenario in the same network You can use better several NTP servers, and point routers to them all. NTP is designed with fault tolerance in mind, even to get better clock timeline. > > Regards > Vivek Aggarwal ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] Dimensioning NTP Server
Aggarwal Vivek-Q4997C wrote: > Hi > Iam planning to have NTP Server for something around 50,000 Clients in > the Network > > Can Anyone guide me in dimensioning the NTP Server. What are the > guidelines that I should take care for dimensioning the NTP Server > I'd probably set up 3 stratum 1 servers at each site and then use multicast to distribute the NTP packets to the clients. The exact configuration can depend a great deal on what the clients need in the way of accuracy and how the network is laid out. While in general network topology is not important to NTP you can reduce the error budget by keeping the network stable. > Also can I two NTP Servers running in active-stand by or in Load > balancing scenario in the same network load-balancing has no meaning to NTP. You send a NTP packet and the server sends a response. You don't need anything in standby, just include all of the relevant servers in the DNS and NTP will do the rest. With the new pool conf option you can have it use all of the addresses listed in the DNS. This is not different from DNS which has no use for a load balancer or standby either. Danny > Regards > Vivek Aggarwal ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] Dimensioning NTP Server
>>> In article <[EMAIL PROTECTED]>, [EMAIL PROTECTED] (Aggarwal Vivek-Q4997C) >>> writes: Aggarwal> Hi Iam planning to have NTP Server for something around 50,000 Aggarwal> Clients in the Network Is this a LAN or a WAN? Have you seen http://support.ntp.org/Support/DesigningYourNTPNetwork ? While I think 1 or 2 machines could handle the load (if the clients all started at the same time it would be fun for a little while), you will do better overall having at least several machines offering NTP service, both in terms of reliability and load. The machines you would need for this service should all be pretty inexpensive. And if you could write up your experience (or email it to me) I would appreciate it. -- Harlan Stenn <[EMAIL PROTECTED]> http://ntpforum.isc.org - be a member! ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] Dimensioning NTP Server
"Aggarwal Vivek-Q4997C" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > Iam planning to have NTP Server for something around 50,000 Clients in > the Network > > Can Anyone guide me in dimensioning the NTP Server. What are the > guidelines that I should take care for dimensioning the NTP Server "Do not start up all clients at once." Under normal conditions, clients will quickly back off to one packet per 1024 seconds. I could scrounge up an old 386SX-16 motherboard for you, but even that isn't going to be fazed by 50 packets per second, I'm afraid. > Also can I two NTP Servers running in active-stand by or in Load > balancing scenario in the same network Load balancing... yes, I think so. I can't think of anything that would go wrong. But the usual way to provide high NTP availability is to simply have all clients query all of four servers all the time. Because it's not only a question of the number of servers likely to be up. The real question is 'what time is it?' when there are four answers, or three, or two, all just a little different. Groetjes, Maarten Wiltink ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
Re: [ntp:questions] Dimensioning NTP Server
Hi Iam planning to have NTP Server for something around 50,000 Clients in the Network Can Anyone guide me in dimensioning the NTP Server. What are the guidelines that I should take care for dimensioning the NTP Server Also can I two NTP Servers running in active-stand by or in Load balancing scenario in the same network Regards Vivek Aggarwal ___ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
