From JumpBox Documentation Wiki

MS Virtual Server Clock Fix

There is a compatibility issue between the older Microsoft Virtualization products and the Linux Kernel used by the JumpBoxes that results in the JumpBox crashing after 4-24 hours of operation. A manual fix must be applied to the JumpBoxes to prevent this from happening. If you want to verify that this is the source of any crashes you may be experiencing, please inspect your logfiles under /var/log/ for a line like this:

Apr 28 06:51:30 helpdesk kernel: [62852.148296] BUG: soft lockup - CPU#0 stuck for 11s! [swapper:0]

The Fix

• SSH to the JumpBox as the admin user
• Edit the grub config file:

sudo nano /boot/grub/menu.lst

• Add clock=pit to the kernel lines, so the first boot section should look like:

title           Ubuntu 8.04, kernel 2.6.24-19-generic
root            (hd0,0)
kernel          /boot/vmlinuz-2.6.24-19-generic root=LABEL=root ro quiet splash vga=785 noreplace-paravirt clock=pit
initrd          /boot/initrd.img-2.6.24-19-generic

Now, save the file and reboot your JumpBox. You should not encounter the crashes at this point.

Recommendation

Changing the clock type as shown above has the drawback of making the guest clock less accurate. You may notice that your guest clock is slow or fast. It might even drift off very quickly. So we recommend that users whos JumpBoxes have access to the internet use NTP to keep their time in sync. Please follow the JumpBox NTP setup instructions.