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I just posted a new version of my VMware backup script. This script is primarily designed to work with VMware Server/GSX running under Linux. However, some of the options will work with VMware ESX.

This new version addresses one of the biggest problems I’ve had with VMware Server. Since snapshots don’t work reliably and they are difficult to fix if they get messed up. Good backups without keeping the VM down for the entire backup where difficult.

This new version adds a new option that allows a much more stable low downtime backup under VMware Server. This new backup option uses LVM snapshots to perform a backup. The downtime is limited to how long it takes to suspend and resume the VM.

In my testing A cold backup of my test webserver VM took 47 Minutes. The downtime for for a backup using an LVM snapshot was 33 seconds this is a great improvement.

There is however, one gotcha. The VM must be stored on an LVM volume.

As always, the most recent version of the script as available at: http://download.dwighthubbard.info/backup

The following is a simple command line that will print the registered VMs and their power state. This works under VMware ESX, VMware server when running under Linux and I believe it will work for VMware workstation under Linux as well.  It’s best to cut and paste this command since it has both front and back tickmarks which can look very similar or the same depending on your browser font.

vmware-cmd -l|while read i; do echo -n `basename “$i”`”: “; vmware-cmd “$i” getstate|awk ‘{print $3}’;done

It is also possible to use the grep command to only get information on VMs that are only powered on or off.

vmware-cmd -l|while read i; do echo -n `basename “$i”`”: “; vmware-cmd “$i” getstate|awk ‘{print $3}’;done|grep on

I’ve been loading VMware ESX on a number of Dell 2950 servers with DRAC-5 Management interfaces as well as several hundred blades in HP C7000 blade chassis using the HP ILO-2 management interfaces on the blades. In my case all my servers are in a remote datacenter and I have never touched any of them. In this article will compare what I’ve seen with both interfaces, I will not be going into depth as I am only talking about functionality that would be used to remotely install an operating system.

Dell DRAC-5

Advantages

• Console access is significantly faster than the HP ILO-2
• The User Interface is fairly straightforward and well laid out.
• Small disk images can be flashed directly to the Flash on the DRAC and presented as a bootable USB drive.

Disadvantages

• The DRAC is insecure by default. It ships with a well known login/password combination.
• The Web interface only works with the insecure Microsoft Internet explorer web browser. Supposedly it will also work with an Ancient version of Linux/Mozilla but I have yet to hear of anyone who actually got it working. Needless to say, this prevents using it from a non-windows system such as a PDA phone, Mac or Linux computer.
• Remote media is unstable. It is possible to mount a CD image on a local system as a remote media. However, the DRAC-5 will at random intervals detach the Image. Although re-attaching the same image will normally allow things to continue without issue.
• If a web window containing a console is closed unexpectedly the DRAC doesn’t always clean up the connection. This can make it impossible to use the DRAC console until the DRAC is reset or the session closed using a command line login to the DRAC.

HP ILO-2

Advantages

• Presents multiple management interfaces. The ILO-2 provides a simple web interface for many common operations as well as providing console access using either Active-X or Java.
• In a blade configuration, the IP address of the ILO-2 device can be pushed to all the ILO-2 devices on the blades from the main blade chassis onboard administrator.
• The blade chassis onboard administrator can provide single signon access to the ILO-2 devices for the blades in that chasis.
• In addition to providing the ability to boot from floppy and CD images like the DRAC, the ILO-2 also allows booting or presenting a local directory as a USB device to the managed system (limited to 1GB in size)

Disadvantages

• The remote media devices on the ILO-2 are unstable and disconnect intermittently, although generally not as frequently as on the DRAC-5. Unfortunately, unlike the DRAC-5 the device cannot be re-connected and used without rebooting/power cycling.
• The Active-X console interface has a menu system that is hard to use and unstable.
  • When using the Active-X integrated console it takes approximately 3 seconds for the menus on the console to start working after a resize event. This is an issue since if the system cannot find a usable device it will reboot every 9 seconds and resize the screen. This causes the console menu to become non-responsive and change position every 9 seconds. This game of keep-away with the menu is extremely frustrating and makes performing power and virtual media operations very difficult.
  • The menus in the Active-X integrated remote console are slow to draw and often times don’t respond to mouse clicks on their options.
• The screen refresh on the ILO-2 consoles (both the Active-X Integrated remote console and the Java console) are extremely slow and totally unusable when the screen is scrolling.

I have uploaded a new version of the cleanvideo script.

It now generates cropped videos that the mythtv frontend and mythtranscode can use.

You can download the new version at: http://download.dwighthubbard.info/cleanvideo.py