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Questions tagged [ntp]

NTP stands for Network Time Protocol, and it is an Internet protocol used to synchronize the clocks of computers to some time reference.

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questionable timeservers in pool.ntp.org?

I've noticed that, after changing the reg settings outlined in Episode 52 of the Stack Overflow podcast to pool.ntp.org, my box keeps requesting time from gordo.foofus.net. The web site hosted on that box is very strange. Is this a valid timeserver?
John
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How to synchronize time on ESXi Windows virtual machines within one second?

I'm a developer and we are using Quartz.Net, widely used scheduling library with SQL backing store to run cluster of jobs servers (VMs on ESXI cluster). Quartz.Net requires that time will be synchronized between job server instances and recommends…
Leotsarev
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NTP Service Auto-Discovery

Are there any methods I could use to provide auto-discovery for NTP? I recently moved to a new job that has a parent company that recently started providing Active Directory. I've been implementing SSSD & other stuff authenticating against AD and…
Keith Shannon
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Time drift

How do you deal with server time drift?
deadprogrammer
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When should NTPd broadcast/broadcastclient be used instead of client/server or peer modes?

The NTP deamon if often used in its simplest mode, which is client/server: you specify one or more server directives in your ntp.conf and your clients will use those servers. In addition to that, when you run your own NTP servers, it is good…
Luke404
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Local or public NTP servers?

For a relatively large network (thousands of hosts) - what are the arguments for and against running a locally managed (pool of) NTP server(s) (perhaps periodically set via some public NTP server) and having all other hosts on the network use that…
BeeOnRope
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How come one of my switches is off by two minutes in spite of ntp?

I just noticed by pure chance that one of my Cisco 4500 switches has its clock going wrong: it is more than 2 minutes behind in spite of seemingly functional ntp. In my opinion, even a single second should not be considered acceptable for the…
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why doesn't ntp recover after an Internet-less startup?

I have a few Linux devices (without TOY chips, so they completely rely on ntp) which may boot without access to Internet (the link to the switch is up). The ntp service will start but obviously no peers will be contacted. I then end up with an ntp…
WoJ
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Why is NTP syncing to LOCAL rather than remote server?

So, I'm trying to debug my current NTP setup, and found that he offset from my single configured server is over 3 seconds, and not adjusting. The asterisk on the LOCAL(0) in the ntpq output seems to indicated that the system is happily syncing with…
JPhi1618
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Replacing sick NTP server source and re-synching (with internal time currently 2 minutes late)

One of the external NTP servers (the primary one--currently) we're using as source seems to not be responding to NTP calls. Unfortunately, on our core router (Cisco 6509), the NTP functionality hasn't switched to the secondary NTP external server…
l0c0b0x
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How to configure ntpd to sync time more frequently?

I need to set ntpd to sync time as often as possible, how to do that? UPD I need to make ntpd adjust system clock more frequently, not poll servers. It's necessary because system clock of my virtual PC drifts too much maxpoll doesn't seem to change…
user626528
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Vmware host time drift

How does one ensure that linux hosts, running on vmware infrastruction 3 or vmware 3 esxi remain in sync with the ntp server. I have found that a linux guest running under esx or esxi has a tendency to have the clock drift in the future. How does…
biosFF
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Will NTP drift the clock backwards

Will NTP move the system clock backwards? I'm thinking about creating unique ids which are partially based on the time. If the clock is moving backwards, I'd need to somehow account for that.
Dave
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Linux ntpd leap second preparation

There will be a leap second on June 30, 2015 at 23:59:60 UTC. I have a Linux based stratum 1 NTP server which uses GPS as a reference clock. The server is using the "default" ntp.org ntpd. How should I prepare for the leap second to ensure that the…
snap
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ntpd: servers stuck on .INIT

I am trying to set up an NTP server for my local network, but ntpd refuses to sync with outer servers. # ntptrace localhost: stratum 16, offset 0.000000, synch distance 0.396285 # ntpq -pn remote refid st t when poll reach …
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