#StackBounty: #ubuntu #virtual-machines #time-synchronization How to prevent relative time shift after restoring a snapshot in Parallels?

Bounty: 100

I am working with a web-based app on an Ubuntu test/development system running in Parallels. At specific dates and times (taken from the system time) some events happen and things are changed in the database. (e.g., a user account is locked, if password was not changed for a certain time, or the status of an object is changed, if a deadline is passed etc.)

To be able to test specific scenarios, I work with snapshots in Parallels to store the state of the system at several key points in time. It can happen that after several months I need to return to a specific point in time to test a specific scenario on the state back then.

My problem is that after restoring the snapshot, the system date is as I want it to be (namely equal to the datetime when the snapshot was taken).

But after several seconds to minutes, the system time changes to some point in time between the real time and the expected (snapshot) time. I have the impression that it is set to the time that has passed relatively. E.g., if I took the snapshot on 2018-02-01 (real time) with the system date of the Ubuntu guest being 2018-01-01 (guest time) and I restore the snapshot on 2018-03-01 (real time), then the Ubuntu guest will eventually be set to 2018-02-01 (guest time) after some minutes.

What I have done so far:

  • Switched off Parallels time sync (according to https://kb.parallels.com/113271)
  • Uninstalled ntp and ntpdate
  • Disabled Automatic Date&Time and Automatic Timezone in Ubuntu desktop settings

The problem seems to be related to hwclock. As an example, I have restored a snapshot from 2018-01-25 (guest time) yesterday, on 2018-05-25 (real time). I executed (immediately after restoring the snapshot):

date ; 
hwclock --show ; 
date -s 2018-01-26 ; 
hwclock --systohc ; 
hwclock --set --date 2018-01-26 ; 
hwclock --show ;

This results in the following output:

Thu Jan 25 18:17:49 CET 2018
2018-03-09 01:01:27.249216+0100
Fri Jan 26 00:00:00 CET 2018
2018-03-09 01:01:27.775701+0100

If I wait some time, the system time will eventually change to the hwclock time – I have not found out why. I also don’t understand why the attempts to set the hwclock time does not work (no error is shown, but the new time is ignored…)

Finally, I also have checked the syslog but there is no hint about the changed date. It just prints an entry for the old date and the next entry is with the new date, no indication what caused the date change.

What have I missed?


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#StackBounty: #azure #virtual-machines #hyper-v #azure-networking Azure VM Nested Hyper-V VM Network Configuration

Bounty: 50

I’m trying to figure out how to share the internet connection from my HOST Azure VM to the VM’s withing Hyper-V inside the HOST VM.

I’ve added two network interfaces to the HOST Azure VM each with static IP’s configured.

Upon creating my Virtual Switch on Hyper-V i’ve associated the secondary NIC on the HOST machine and the internet connection is not passing through. I do have “Allow management operating system to share this network adapter” checked.

My intent is to create a Domain Controller with DHCP as a Hyper-V VM within my host machine and create subsequent Hyper-V VM’s on the HOST machine for purposes of exchange, SQL, etc… But I need to get my primary Active Directory VM up and running and can’t seem to figure out how to pass the internet connection from the HOST onto my first Hyper-V VM.

Any help, ideas, input appreciated.

Some context for this question:
I’m investigating setting up a Hyper-V network for Microsoft Exchange. My plan is to create 1 Azure VM and install Hyper-V and multiple VM’s inside for Active Directory, Exchange, DNS, DCHP to setup a public facing exchange server.


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#StackBounty: #monitoring #virtual-machines #docker #graphite VM CPU usage at 100%

Bounty: 100

CPU usage on our metrics box is at 100% intermittently causing:
‘Internal server error’ when rendering Grafana dashboards

The only application running on our machine is Docker with 3 subcontainers

  • cadvisor
  • graphite

  • grafana

Machine spec
OS Version Ubuntu 16.04 LTS
Release 16.04 (xenial)
Kernel Version 4.4.0-103-generic
Docker Version 17.09.0-ce
CPU 4 cores
Memory 4096 MB
Memory reservation is unlimited
Network adapter mgnt

Storage
Driver overlay2
Backing Filesystem extfs
Supports d_type true
Native Overlay Diff true

Memory swap limit is 2.00GB

Here is a snippet from cAdvisor:

enter image description here

The kworker and ksoftirqd processes change status constently from ‘D’ to ‘R’ to ‘S’

Are the machine specs correct for this setup?
How can I get the CPU usage to ‘normal’ levels?

EDIT

After increasing memory from 4GB to 8GB the CPU usage gradually increased:
enter image description here


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#StackBounty: #virtual-machines #hyper-v #scdpm Hyper-V virtual machine recovery checkpoint problems

Bounty: 50

One of my virtual machines, backed up by DPM, is repeatedly creating recovery checkpoints and exponentially increasing the storage space required on the host.

Three servers involved:

  • Server 2012 R2, Hyper-V host [HOST/ASH-LIBRARY]
  • Server 2008 R2, virtual machine [VM/ASH-PRINTERS] run on HOST
  • Server 2012 R2, physical machine [DPM/AHSSCCM01], running SCCM 2012 R2 with DPM R2 4.2

HOST is backed up by DPM, and VM is part of that:

DPM backing up VM

VM is creating Backup checkpoints every day… and not getting rid of any of them when they’re no longer needed:

VM snapshots

From the reading I’ve done online, this may be because one of the earlier checkpoints failed to create properly – and now it can’t be removed, so DPM keeps adding to the tree and being unable to remove any of them.

I’m looking for a way to remove these checkpoints and free up space on HOST’s hard drive. Obviously I could just delete the files, but that won’t stop the on-going problem.

I have tried the following:

  • Disk merge, latest AVHD to parent VHD, no change
  • Deleting the Checkpoint subtree, “Cannot delete a checkpoint subtree containing a recovery checkpoint”
  • Exporting the latest checkpoint to then try and mount a new VM from it, “Cannot merge automatic VHD chain”
  • Running the command Get-VMSnapshot -VMName ASH-Printers | Remove-VMSnapshot, results in Error 0x80070002: The system cannot find the file specified (which may be because HOST’s hard drive only has 6Gb space remaining … but I have no room to manoeuvre the VMs to test this)

What else can I try to fix this problem?


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#StackBounty: #linux #virtual-machines #hyper-v #rhel7 #bare-metal Installed OS to external drive using a VM, now won't boot on bar…

Bounty: 50

I have a USB hard drive. (The USB connector for that drive is actually super flaky and disconnects if you breathe on it too hard, but I don’t think that’s the problem here.)

I have a laptop without a DVD drive, and only one USB port. (Actually, it has more USB ports, but they seem to not work. Hmm, why is everything broken? Come to think of it, the USB cable was my fault, but I think the USB ports came that way.)

I tried to follow the instructions here, adapted to my situation: https://developers.redhat.com/products/rhel/hello-world/.

In particular, I downloaded the bootable ISO, created a virtual machine in Hyper-V on Windows 10 (Professional), and told it to boot from the ISO and install to my external drive. The installation succeed and eventually I saw a pretty GUI prompting me to log in. I then shut down the VM and declared victory.

This turned out to be premature. When I try booting from my USB drive, the boot process begins, but it never completes, and doesn’t even seem to get very far. It announces the name of the OS (in particular, Red Hat Enterprise Linux 7), so it’s not totally broken, but something is still wrong and I don’t know what.


Get this bounty!!!

#StackBounty: #linux #virtual-machines #hyper-v #rhel7 #bare-metal Installed OS to external drive using a VM, now won't boot on bar…

Bounty: 50

I have a USB hard drive. (The USB connector for that drive is actually super flaky and disconnects if you breathe on it too hard, but I don’t think that’s the problem here.)

I have a laptop without a DVD drive, and only one USB port. (Actually, it has more USB ports, but they seem to not work. Hmm, why is everything broken? Come to think of it, the USB cable was my fault, but I think the USB ports came that way.)

I tried to follow the instructions here, adapted to my situation: https://developers.redhat.com/products/rhel/hello-world/.

In particular, I downloaded the bootable ISO, created a virtual machine in Hyper-V on Windows 10 (Professional), and told it to boot from the ISO and install to my external drive. The installation succeed and eventually I saw a pretty GUI prompting me to log in. I then shut down the VM and declared victory.

This turned out to be premature. When I try booting from my USB drive, the boot process begins, but it never completes, and doesn’t even seem to get very far. It announces the name of the OS (in particular, Red Hat Enterprise Linux 7), so it’s not totally broken, but something is still wrong and I don’t know what.


Get this bounty!!!

#StackBounty: #linux #virtual-machines #hyper-v #rhel7 #bare-metal Installed OS to external drive using a VM, now won't boot on bar…

Bounty: 50

I have a USB hard drive. (The USB connector for that drive is actually super flaky and disconnects if you breathe on it too hard, but I don’t think that’s the problem here.)

I have a laptop without a DVD drive, and only one USB port. (Actually, it has more USB ports, but they seem to not work. Hmm, why is everything broken? Come to think of it, the USB cable was my fault, but I think the USB ports came that way.)

I tried to follow the instructions here, adapted to my situation: https://developers.redhat.com/products/rhel/hello-world/.

In particular, I downloaded the bootable ISO, created a virtual machine in Hyper-V on Windows 10 (Professional), and told it to boot from the ISO and install to my external drive. The installation succeed and eventually I saw a pretty GUI prompting me to log in. I then shut down the VM and declared victory.

This turned out to be premature. When I try booting from my USB drive, the boot process begins, but it never completes, and doesn’t even seem to get very far. It announces the name of the OS (in particular, Red Hat Enterprise Linux 7), so it’s not totally broken, but something is still wrong and I don’t know what.


Get this bounty!!!

#StackBounty: #linux #virtual-machines #hyper-v #rhel7 #bare-metal Installed OS to external drive using a VM, now won't boot on bar…

Bounty: 50

I have a USB hard drive. (The USB connector for that drive is actually super flaky and disconnects if you breathe on it too hard, but I don’t think that’s the problem here.)

I have a laptop without a DVD drive, and only one USB port. (Actually, it has more USB ports, but they seem to not work. Hmm, why is everything broken? Come to think of it, the USB cable was my fault, but I think the USB ports came that way.)

I tried to follow the instructions here, adapted to my situation: https://developers.redhat.com/products/rhel/hello-world/.

In particular, I downloaded the bootable ISO, created a virtual machine in Hyper-V on Windows 10 (Professional), and told it to boot from the ISO and install to my external drive. The installation succeed and eventually I saw a pretty GUI prompting me to log in. I then shut down the VM and declared victory.

This turned out to be premature. When I try booting from my USB drive, the boot process begins, but it never completes, and doesn’t even seem to get very far. It announces the name of the OS (in particular, Red Hat Enterprise Linux 7), so it’s not totally broken, but something is still wrong and I don’t know what.


Get this bounty!!!

#StackBounty: #linux #virtual-machines #hyper-v #rhel7 #bare-metal Installed OS to external drive using a VM, now won't boot on bar…

Bounty: 50

I have a USB hard drive. (The USB connector for that drive is actually super flaky and disconnects if you breathe on it too hard, but I don’t think that’s the problem here.)

I have a laptop without a DVD drive, and only one USB port. (Actually, it has more USB ports, but they seem to not work. Hmm, why is everything broken? Come to think of it, the USB cable was my fault, but I think the USB ports came that way.)

I tried to follow the instructions here, adapted to my situation: https://developers.redhat.com/products/rhel/hello-world/.

In particular, I downloaded the bootable ISO, created a virtual machine in Hyper-V on Windows 10 (Professional), and told it to boot from the ISO and install to my external drive. The installation succeed and eventually I saw a pretty GUI prompting me to log in. I then shut down the VM and declared victory.

This turned out to be premature. When I try booting from my USB drive, the boot process begins, but it never completes, and doesn’t even seem to get very far. It announces the name of the OS (in particular, Red Hat Enterprise Linux 7), so it’s not totally broken, but something is still wrong and I don’t know what.


Get this bounty!!!

#StackBounty: #linux #virtual-machines #hyper-v #rhel7 #bare-metal Installed OS to external drive using a VM, now won't boot on bar…

Bounty: 50

I have a USB hard drive. (The USB connector for that drive is actually super flaky and disconnects if you breathe on it too hard, but I don’t think that’s the problem here.)

I have a laptop without a DVD drive, and only one USB port. (Actually, it has more USB ports, but they seem to not work. Hmm, why is everything broken? Come to think of it, the USB cable was my fault, but I think the USB ports came that way.)

I tried to follow the instructions here, adapted to my situation: https://developers.redhat.com/products/rhel/hello-world/.

In particular, I downloaded the bootable ISO, created a virtual machine in Hyper-V on Windows 10 (Professional), and told it to boot from the ISO and install to my external drive. The installation succeed and eventually I saw a pretty GUI prompting me to log in. I then shut down the VM and declared victory.

This turned out to be premature. When I try booting from my USB drive, the boot process begins, but it never completes, and doesn’t even seem to get very far. It announces the name of the OS (in particular, Red Hat Enterprise Linux 7), so it’s not totally broken, but something is still wrong and I don’t know what.


Get this bounty!!!