What is VM clock drift?
VMware® virtual machines use several techniques to minimize and conceal differences in timing performance, but the differences can still sometimes cause timekeeping inaccuracies and other problems in software running in a virtual machine. When this occurs, it’s called time drift.
What is time drift in Linux?
When your server’s time doesn’t match an authoritative time, such as ntp.org, you have a problem called time drift. This problem is incredibly common and happens slowly over weeks and months. To easily check the time drift, compare the server’s current date and time to The Official NIST Time.
What is tinker in NTP?
Tip: tinker panic 0 is an NTP directive that instructs the NTPD to not panic and exit if the original clock behaves randomly. It must always appear first in the ntp. conf file. If the node is installed on a virtual machine, check if any section in the ntpd.
What is NTP drift file?
The ntpd. drift file records the latest estimate of clock frequency error. If this value gets too high, this can be an indicator of large error between the system clock and the real time.
What is tinker panic?
“The tinker panic value of 0 tells NTP that no matter what the time offset is, not to panic and exit. This is recommended for virtual machines because virtual machines have no physical clock and can be paused at anytime and started back up hours later. “
What is ntpq command in Linux?
The ntpq command queries the NTP servers running on the hosts specified which implement the recommended NTP mode 6 control message format about current state and can request changes in that state. It runs either in interactive mode or by using command-line arguments.
Why does the clock on my Azure VM drift?
In this configuration, the clock will drift over time. In newer Linux distributions on Azure, VMs can use the VMICTimeSync provider, included in the Linux integration services (LIS), to query for clock updates from the host more frequently. Virtual machine interactions with the host can also affect the clock.
How do I fix the drift in Linux?
If you still lose ticks, then any other solution will have major drift too. If you can, use a guest OS that has a low frequency tick rate. Newer versions of Linux come with 1000Hz ticks, but it used only to be 100Hz. That seems easier for the host to deliver. A kernel rebuild is usually needed to change the HZ value. Show activity on this post.
Why does my NTP time drift?
Otherwise you will have two synchronization mechanisms in contention. In the time between NTP time synchronization intervals, the time is dependent on the “local clock” of your virtual machine. Since there is no real local clock, it’s possible this is the cause of the drift.
How do virtual machines get time in azure?
Virtual machines in Azure can either depend on their host to pass the accurate time ( host time) on to the VM or the VM can directly get time from a time server, or a combination of both. On stand-alone hardware, the Linux OS only reads the host hardware clock on boot.