Windows Server 2008 R2 System Keep Changing Time Every Hour

Windows Server 2008 R2 is a popular version of Microsoft's server operating system. This article focuses on a specific issue that can occur on a physical machine running Hyper-V and several virtual machines. The problem is that the host machine adjusts the time backwards by one hour every hour.

Understanding the Problem

In a Windows Server 2008 R2 system with Hyper-V turned on, you may encounter an issue where the host machine's system time changes backwards by one hour every hour. This can cause problems for the virtual machines running on the host because their system time will also change unexpectedly.

Impact of System Time Changes

The system time of a server is critical for many reasons. For example, it affects the logging of events, the scheduling of tasks, and the synchronization of network services. When the system time changes unexpectedly, it can cause the following issues:

• Application failures due to incorrect date/time information stored in the system.
• Security issues related to the expiration or renewal of certificates.
• Incorrect data and time stamps in logs and reports.

Identifying the Cause

There can be several reasons for the system time changing unexpectedly. Here are some common causes to look out for:

• Windows Time service (W32time) synchronization issues.
• Hardware clock (CMOS clock) issues.
• Hyper-V time synchronization issues.

Checking the Windows Time Service

The Windows Time service is responsible for maintaining the time synchronization between the host and virtual machines. You can check the current status of the Windows Time service using the following steps:

1. Press Windows + R and type cmd to open a command prompt.
2. Type w32tm /query /status in the command prompt and press Enter.
3. Check the status of the Windows Time service. It should show "Idle" or "Active" under the "Current Status" section.

Checking the Hardware Clock

The hardware clock (CMOS clock) is the real-time clock (RTC) on the motherboard. You can check the current time and date settings of the hardware clock by booting into the BIOS or UEFI firmware settings.

Checking Hyper-V Time Synchronization

In a Hyper-V environment, the virtual machines synchronize their time with the host machine. You can check the current time synchronization settings using the following steps:

1. Open the Hyper-V Manager.
2. Select the virtual machine and click on "Settings" from the action pane.
3. Select "Integration Services" and check the status of the "Time synchronization" service.

Resolving the Issue

Once you have identified the cause of the system time changing, you can take the appropriate steps to resolve the issue. Here are some steps you can take:

• Configure the Windows Time service to synchronize with a reliable time source.
• Check and update the hardware clock time and date settings.
• Configure Hyper-V time synchronization settings.

Configuring the Windows Time Service

You can configure the Windows Time service to synchronize with a reliable time source using the following steps:

1. Press Windows + R and type cmd to open a command prompt.
Type w32tm /config /syncfromflags:manual /manualpeerlist:pool.ntp.org in the command prompt and press Enter.
2. Restart the Windows Time service by typing net stop w32time && net start w32time in the command prompt.
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Checking and Updating the Hardware Clock

You can check and update the hardware clock time and date settings by booting into the BIOS or UEFI firmware settings and following the manufacturer's instructions.

Configuring Hyper-V Time Synchronization

You can configure Hyper-V time synchronization settings by following these steps:

1. Open the Hyper-V Manager.
2. Select the virtual machine and click on "Settings" from the action pane.
3. Select "Integration Services" and uncheck the "Time synchronization" service.
4. Click on "OK" to save the changes.

• The system time changing unexpectedly in a Windows Server 2008 R2 system with Hyper-V can cause many issues.
• Common causes include Windows Time service synchronization issues, hardware clock issues, and Hyper-V time synchronization issues.
• You can resolve the issue by configuring the Windows Time service, checking and updating the hardware clock, and configuring Hyper-V time synchronization settings.

References

• Investigating the Windows Time Service
• Windows Time Service Tools and Settings
• Manage Integration Services for Virtual Machines