VBScripts BLOG

We all have our weak moments and do stupid things. Just like I did with our virtual center database transaction log. I did not set a maximum growth limit to which the transaction log could grow and so it ran out of disc space. And our Virtual Center server stop running because of it. So I needed to trash the transaction log and fast. I made this little SQL script that can be run with SQL Query Analyzer.

The very simpel solution to this problem:

USE [YouVirtualCenterDB]

BACKUP LOG [YouVirtualCenterDB] WITH TRUNCATE_ONLY

DBCC SHRINKFILE([YouVirtualCenterDB]_log,2)

Remeber this will trash your transaction log. It will not be backuped to disc it will be written to dev NULL. This script is only to be used if your sure you don’t need the transaction log or you need the database running again in a very short time and there is no other way.

Hope it helps some of you.

Login Virtual Session Index (Login VSI), is a free and easy to use benchmarking methodology from Login Consultants. The Login VSI is a complete toolset that allows you to easily compare scalability all of today’s major virtualization platforms and technologies.

Login VSI supports most recent Windows OS’s (including 32 and 64bit), Office 2003 and 2007, all major application streaming technologies and most importantly both SBC and VDI. The next beta (out in a couple of weeks), will also include full support for benchmarking VDI environments”
“Because the setup is so simple there is an infinite amount of combinations and technologies you can now compare. For instance, you can also measure the relative impact of a virus scanner or performance optimization technologies. Additionally, Login VSI will be a perfect tool to compare scalability of different virtualization platforms.”
Login VSI can be downloaded from here.

To Source: Login consultants

NetApp have released a powerful new addition to the Open Systems SnapVault range for VMware Virtual Infrastructure.

OSSV installs directly into the VMware ESX service console and acts as a very light-weight interface to backup Virtual Machines on NetApp storage and non-NetApp storage. It works best with NetApp Protection Manager, but works well as a stand-alone product.  There’s also an excellent Best Practice guide for OSSV available here.

To source: Paul Shannon

The last few weeks it wasn’t fun having a VMWare ESX environment. SQL transaction logs that were out of control, ESX server that lost there iSCSI connection, etc.

One of the thing I was investigating was the size of our virtual center database. What I found was that data (events, tasks, etc) is being stored in the database but never deleted.

When browsing the VMWare site I found this SQL script in the knowledgebase of VMWare. The script inspects the database for data older than a certain date. The script works for virtual center 2.0 and 2.5.

———————————————————–
– Use one of these methods to specify the data cutoff date
– SET @CUTOFF_DATE = GETUTCDATE()-180
SET @CUTOFF_DATE = ‘2008/01/01′ <– cut off date
———————————————————–

Default the script count the rows that can be deleted. If you set deletedata to 1 than the script will purge the data from the database.I removed 2.5 million rows from our Virtual Center database and we noticed an increase of performance.

Use it carefully!!! Make your backups.

At this time VMWare has released the 3.0.2 update for ESX. But before you install this update you must think twice. A lot of people have driver problems. VMWare has updated drivers for it’s supported hardware like network, iSCSI, etc.

The problem people experience when upgrading is network latency and iSCSI problems. There is no information from VMWare at this time.

We will wait for VMWare ESX 3.1 that is due in september 2007.

After writing LUN cloning with NetApp and templating VM’s with RDM I ran in to a problem. LUN cloning was only possible on the same volume. But we created a volume with templates that we want to clone to another volume because templates won’t reside on the same volume as the production virtual machine. After some digging I found the command ndmpcopy. This utility gives you the option to copy a LUN or volume.
So if you want to copy a LUN from your template volume to your production volume you’ll need to do the following:

The steps

ndmpcopy /vol/[Template Vol path]/[LUN] /vol/[destination vol]/

It is also possible to create a Qtree directly. It doesn’t have to exists before copying the LUN. It will look something like this.

ndmpcopy /vol/[Template Volume path]/[LUN] /vol/[destination volume]/[Qtree]

NOTE: this will take quite a lot of CPU power from the filer so be careful when you copy your LUN.
Now you have copied your LUN you will hva to rename it because if you copy a LUN you cannot rename the LUN during copying. For renaming you use lun move. The Qtree is optional again.

Lun move /vol/[ volume]/[Qtree]/[LUN original name] /vol/[ volume]/[Qtree]/[LUN new name]

Now you have you LUN for your new virtual machine. You can add this LUN to your ESX enviorment and import the Virtual Machine or add it as a disc to a other Virtual Machine.

In this post I will discuss the use of lun cloning to get a very easy way of deploying virtual machines. When using RDM’s on your NetApp filer to store your virtual machines templates within VMWare become useless. NetApp has the following solution for it and it called LUN CLONING or creating your golden lun. This lun is your template and will serve as the foundation of your Virtual Machines. You have to create a LUN for all operating systems you support on VMWare. Clones on NetApp are rely on the snapshot technology of NetApp. with other words you need a snapshot of the lun you want to clone. After a snapshot is created or the right snapshot is chosen you can create your clone. I will take you through the step in a short time.Two scenarios are possible.

Scenario one

You want to create a Virtual test environment of a running virtual machine. To do this you can create a LUN clone. This is a very small copy of the original machine because you clone the snapshot and only changes are captured in the snapshot. So your clone is zero bytes in the beginning and will grow if the clone exists longer and the original LUN changes.

Scenario two

You wish to create a machine that is based on a LUN but is a separate machine. Mostly done if the LUN you clone is your “template LUN”.  In this case you want to split the LUN from its Parent. This is done with the LUN clone split operation.The stepsChoose which snapshot you want to use for your clone.

The steps

snap list vol_name 

This command will give you a list of available snapshots.

Lun clone create target_LUNpath –b parent_lunpath parent_snap

This command creates the clone. The parent_snap the LUN is cloned from will be locked. It cannot be deleted. The only way to remove the parent_snap is to destroy or split it. Now you have completed scenario one. If you want scenario two use the following command to split the clone from it’s parent.

Lun clone split start LUN_path

This splits the clone from its parent. The following command gives you a status report.

Lun clone split status LUN_path