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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Does windows server provide a standards-based NTP service?
We use a PHP script for syncing time against a NTP time server. All of it works, but when working with windows server, the script fails.
Is there a modified version of NTP working inside the original ...
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Main DC is no longer NTP or hold FSMOs
Good Afternoon,
We two virtual DC and one local physical read only DC. When we moved our data center offsite with a warm backup site we p to v our DC’s and DC1 was the master schema.
While ...
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How to accommodate two sets of NTP servers
I have a case where, within one company, half of the devices synchronize to a set of NTP servers (including a GPS based one), and the other one on another set (also including stratum 1 servers).
I ...
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Server times off by over 1 minute after recently syncing
I manually synced the times (and matched hardware times) on two servers A and B.
NTP was running on both machines, so I made sure the /etc/ntp.conf files were identical (the time servers on B were ...
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Neglected services on old DC - how to move to new DC?
We have installed a new Server 2012.
The new server: DC3 (192.168.0.3), has been promoted, and is now our main DC (includes : DNS, DHCP)
Schema master DC3.domain
Domain naming master ...
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udev rule running setserial low_latency don't work
My server runs Ubuntu 14.04.1. I created udev rules in /etc/udev/rules.d/09-pps.rules to get GPS with PPS support work.
KERNEL=="ttyS0", SYMLINK+="gps0", MODE="0666"
KERNEL=="ttyS0", RUN+="/bin/...
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NTP offset between PDCe and DC (Both Hyper-V)
I'm facing an issue, here is the context:
1 PDCe (192.168.1.3 and Hyper-V virtualized) is set as NTP server, its source for time is VM IC Time Synchronization.
1 DC (Hyper-V virtualized) is ...
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Windows Server NTP Authenication
I have setup an NTP Server on a Windows Server 2008.
The Time synchronization works with Windows Clients and Non Domain Clients but now i have switches that want to authenticate against NTP Server and ...
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How should I manage and troubleshoot NTP issues?
For some time now I've been fighting with some NTP issues in my company's network and I'm having a hard time to understand how the commands combine with the service.
For example:
In the server's /etc/...
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SES time sync error
My SES setup was running fine for the last 6 months without any issues. All of a sudden it stopped working yesterday and I'm gettinng the infamous time sync error.
Naturally I assumed ntpd had ...
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How can I have ntpdate ignore skew?
During a server bootstrap process, I want to explicitly run ntpdate rather than rely on the ntp daemon. However, the clock can be severely skewed at this point in time, which causes an error when ...
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How can I test that I am correctly setting a new ntp server?
I have a config script that is configuring the ntp server of a machine (which is running Ubuntu 14.04) by stripping lines matching ^server .* from /etc/ntp.conf and adding a new line server new.ntp....
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ntp daemon seems useless and why my server date time is far behind my local time
I've installed ntp daemon in ubuntu to sync my date time with the network time. Now my time on the server is 11:00 while my PC date/time is 19:30.
Now all my transactions date/times are logged ...
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Nagios NTP, discarding peer
We're using nagios check_ntp_time for monitoring time on our servers. Unfortunately the service is flapping. And reporting a lot of false-positives. It happens everytime for random server in random ...
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ntpdate -d Server dropped Strata too high
I cannot sync with a NTP source thats coming from an internal router/firewall.
Anyone help ?
ntppdate -d 192.168.92.82
6 Jun 11:57:30 ntpdate[5011]: ntpdate [email protected] Tue Feb 24 06:32:26 EST ...
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Why doesn't the time match on two Windows Domain Controllers despite resync?
In my domain there are two domain controllers, there is a gap of 3 minutes between their times and than I can find this difference between many clients (it depends on their DC).
If I run this command:...
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Windows Server system time drifts badly on Amazon EC2 instance
We've been using an EC2 micro instance for a little remote monitoring for the past few weeks, and it's bothered me badly how the system time is never accurate; no matter how much fighting I did with ...
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CentOS VM, NTP synchronization problems
We have three CentOS 5.9 VMs on an ESX3.5 host.
Because of the nature of the services we provide it is required that the NTP time is synchronized and the time is correct on all three of them.
...
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Virtual guest: NTP sync with host
Is there any way to get a virtual guest to only query it's current host for NTP?
I'm not talking about configuring ntp.conf with the host's IP here either as VLAN's & firewalls may block that ...
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Real-time clock is wrong (from hours to years), one-time non-monotonic change at boot needed. Can Chrony solve this?
I can't guarantee a sane real-time clock on some machines (the time might be wrong by hours, months or even years). Since I also have intermittent networking, I set up Chrony in the hopes it could fix ...
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Why is the time on my Server 2008 R2 DC wrong? It's syncing to ntp.org, it claims
OK. After a lot of fun with syncing time across my workstations, I got that sorted out. My workstations are now perfectly synced with my Server 2008 R2 Domain Controller (physical server, not virtual)....
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Multiple NTP Server Instances on One Server (Linux)
Is it possible to run multiple NTP server instances on the same system? We're using CentOS for our NTP system and want to synchronize specific time depending on what interface the client comes in on. ...
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Group Policy for Time Sync = ARP Flood?
I have a Windows Server 2008 R2 domain controller and a bunch of workstations of various versions of Windows - XP SP3, Vista, 7, 8.1. Time sync wasn't working correctly on a few PCs so I followed the ...
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How to configure a Cisco Catalyst 2960 to synchronize with an NTP server
I would like to synchronize a Cisco Catalyst 2960 series switch with a publicly available NTP server such as time.apple.com. I have reviewed the knowledge base article here:
Catalyst 2960 ...
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Windows server and AWS clock synchronization
I have a Windows 7 computer that communicates with Amazon Web Servers (S3, SES). This server uses windows internet time for clock synchronization time.windows.com. On my linux machines I ran into ...
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What can be done to improve time synchronization on networks with sporadic internet access?
I'm looking for advice setting up time servers for a very non-typical network. I support many closed networks that have occasional access to the internet. A network would get access most days for a ...
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Troubleshooting unwanted NTP Traffic
A domain controller running Windows Server 2012 is sending NTP and NETBIOS traffic to an address that has never been configured as a time provider. The server logs give no indication that any NTP ...
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NTP sync time frequently on Windows 7
I have several Win7 64bit configurations - local dev machine, remote server, VPS.
I'm running time sensitive tasks on all of them, therefore I need Windows Time service to:
Sync
Sync well (&...
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ntp is not syncing on centos server but gets response from remote server
I have googled for days before asking and I feel like I have tried everything but ntp is still not updating the time of the system automatically. I have left it running for days and still I get the ...
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Set NTP not to receive time from peers on Ubuntu
In my /etc/ntp.conf, it says
By default, exchange time with everybody, but don't allow configuration.
restrict -4 default kod notrap nomodify nopeer noquery
restrict -6 default kod notrap nomodify ...
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Domain member as ntp server for other (non-domain) network
I am attempting to synchronize the date and time for a number of computers belonging to a non-domain, statically configured network (e.g. computer B in illustration) with a node which is residing in a ...
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Set a system's time server to itself
I work on a standalone network that has 3 domain controllers all running Server 2008 r2. Two of the servers are physical (DC1 / DC2) and one is virtual (DC3).
I want all my systems to refer to DC1 as ...
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How can I select ntp the time source for a system?
I have two Windows 2008 servers running Meinburg NTP. When I run ntpq.exe -p from one, I see that there are sources specified as current, selected, or discarded (via a +, -, or *). On another system, ...
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Both my ntp servers are marked as falsetickers in the status [closed]
I have a linux box, set up with two ntp servers to sync.
This box in case, was extremely out of sync (61 seconds) before it was forced sync.
The following outputs are 1 hour after this sync.
When ...
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IP auto changed on Win2k8 VM
I'm having a problem with my Win2k8 virtual machine.
After the virtual machine boot, it gets an IP address from DHCP. But later on, NTP makes a big time shift, so Windows automatically renew (in fact ...
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DDOS using ntp server
I've heard about new kind of DDOS where ntp is used for reflection .
My questions are really simple :
Can you please give details on how they work and clarify? Since ntp is ran over UDP, I suppose ...
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ntpd -gq do not working on CentOS 6.4
when I'm running 'ntpd -gq' from CentOS 5.10 (i686) the time is synced, but in CentOS 6.4 (x86_64) the command gets stuck (I need to stop it using ctl+c).
Any idea hoe to fix it?
EDIT:
iptables -...
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ntpd default rate limiting?
I've got about 70 linux instances running on an OpenStack cluster that currently consists of two compute nodes and one controller. Also, these machines live in a RackSpace DC as part of their 'Private ...
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Easiest Way to Keep Time Synced on VMware Cluster
I have a three host VMware cluster (5.1) running mainly windows 2008r2 servers with a single DC. I'm having allot of problems with time drift across the servers and while I've found several articles (...
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Setting time back on a production linux server
I am having an issue with the time on a production linux server being 2 hours fast. I need the time to be accurate for a particular project I'm working on, but am a little nervous to change it, as I'm ...
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Synchronizing RODCs to NTP servers?
I've read this nice article from Gareth Hooper regarding Domain Controller syncing to external time sources. In essence, he wrote that although Microsoft don't actually condone the practice, it's a ...
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Why does ntpd need to bind external interfaces to sync the local clock?
I wanted to tighten my security so I don't want to open any ports that are not really needed. I have no intentions of running an ntp server for other people to use, I only run the ntp daemon to keep ...
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Server 2008 will not sync with NTP [closed]
I recently got given a server 2008 r1 machine and thought I would set it up to help maintain my small work network of 10 PCs better.
The issue I am having is that I cannot get it to sync with an ...
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How to configure NTP has a TAI or GPS time reference?
For our project, we would like to have all servers and systems synchronised to a linear time reference (without leap second).
Therefore, we would discard UTC but are very interested in advertising ...
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Fake SNTP server for testing
I want to setup an SNTP server for testing purposes that
can be set to any arbitrary value (for example testing DST behaviour of the device under test)
serve only on eth1 on my RedHat Enterprise ...
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Why should I need a tweak to force VMware ESXi 5 to sync time with Windows NTP server
I'm plagued by a seemingly simple but actually troublesome problem, so I ask for help here.
Symptom
I installed an instance of VMware ESXi 5.1 inside VMware Workstation to learn about various ESXi ...
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Linux kernel detecting wrong processor frequency
After a cold boot of a 6.0.8 Debian server (HP ProLiant), ntpd played havoc with system time: offset and jitter with respect to the usual and reliable reference time servers growing without limit. (...
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The wisdom of 'server 127.127.1.0' in ntp.conf for virtual servers
Considering the 'undisciplined local clock' on VMs is not what you'd call accurate in most cases, how wise is it to include lines such as these in your NTP configuration?
# Undisciplined Local Clock. ...
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How to make NTP work despite a high offset?
Recently I have kickstarted some servers that had their time off by a month in the bios. The time in the bios said it was a random time/date in May, while it was June.
This caused NTP not to work, ...
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How can I defend against a DRDoS exploiting NTP server on an ESXi host?
Recently, we had some problems with one of our ESXi servers, caused by the NTP Server DRDoS Amplification Attack using ntpdc.
How do I configure the NTP server on ESXi to not be exposed to this DDoS ...
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