Yellow Bricks

by Duncan Epping

Tools

VMDK alignment part two…

· ·

Yesterday I posted about the mbrscan and mbralign tool that NetApp created. This triggered Nick Triantos of NetApp to write an excellent detailed technical article on why you need to set the alignment:

When setup routine queries the CHS (Cylinder / Head / Sector) information of the disk from the BIOS, the CHS data doesn’t actually corresponded to anything physical. At large LUN sizes, the S number (sectors per track) is always reported as 63, so partitioning is set at 63 sector starting offset.

The problem is that 63 sectors, corresponds to 32256 bytes or 31.5KB, which does not align with storage array’s logical block size. Physical disk blocks always correspond to 512 bytes in size, but for efficiency and performance reasons, disk arrays use a logical block size unit that is a multiple of the physical block size.

For the complete story visit Nick’s Blog on the NetApp website.

Check your VM’s alignment…

· ·

I’ve been test driving a script called “mbrscan” for a while now. Today I noticed that this script had already been released a couple of weeks ago. The cool thing about the script is that you can check the alignment of the VM’s filesystem from the outside. The script runs directly on the service console of ESX. NetApp’s Nick Triantos describes it as follows:

There’s a new utility that has been added, called mbrscan. The purpose of mbrscan is to identify whether or not a VM has properly aligned partitions. The script will run successfully under two conditions: a) The VM is powered off b) the VM has VMsnaps. The script will error out if none of the above two conditions are satisfied simply because the VMDK(s) are locked.

This can be very useful to identify possible performance issues within just a matter of seconds. Combine this command with “vmware-cmd” to create and remove snapshots and you’ll have the results for you entire environment within minutes.

Now that you just received your results the real question would be:”How am I going to modify this without destroying the data?”

At this point in time that’s not possible. But I know NetApp is working on a tool called “mbralign”. This tool will make it possible to align the filesystem from outside the VM.

The mbrscan tool is part of the “Unified Host Utilities Kit” which reached version 5. The toolkit isn’t available for everyone, you will need a now.netapp.com/ to be able to download it.

UPDATE: MBRSCAN is a binary not an editable script, and the script version has been floating around for a while now…

Cool Tool Update: RVTools 2.2

· ·

I’ve wrote about this tool several times so most of you must have tested it by now and are probably actively using it: RVTools. Rob just notified me that he uploaded a brand new version of his tool. The following have been added to version 2.2:

  • New vDatastore tab. The “vDatastore” tab displays for each datastore the name, connectivity status, file system type, number of virtual machines on the datastore, total capacity in MB’s, free capacity in MB’s, multiple host access indication and the url.
  • Your custom defined fields are now visible on most of the tab-pages
  • New menu option “export data to csv file”
  • New “upgrade policy” field on vTools tab-page
  • New “Sync time with host” field on vTools tab-page
  • The field “OS” which is displayed on most of the tab-pages now displays the name of the guest OS according to the VMware Tools. In previous versions we used the configuration value. The vTools tab displays both “OS” fields.

Here’s a screenshot of the new tab “vDatastore”:

If you’ve never used RVTools before besure to check it out, it’s worth it. And if you are already using it download it and upgrade!

Veeam Management Pack for VMware 4.0

· ·

Veeam just announced 4.0 of the “Management Pack for VMware”, also known as NWorks:

Version 4.0 includes comprehensive end-to-end monitoring from ESX Cluster, to ESX Host, to Virtual Machine and to Applications inside the VM. The nworks/Veeam MP now provides integration of application and service data with the VI3 topology. This breakthrough functionality enables a fully integrated picture, with end-to-end monitoring from ESX Servers through to the enterprise applications, such as SQL Server, Active Directory and Microsoft Exchange running inside virtual machines.

Version 4.0 also includes new features such as CIM SMASH hardware sensor status and alerts, graphical representations of data stores, flexible collection intervals, VirtualCenter 2.5 performance counters, and more!

The cool thing about this solution is that is doesn’t rquire agents on ESX or any kind of helper for that matter. Veeam “Management Pack for VMware” relies on the VMware API/SDK, which assures that 4.0 is also fully supported for ESXi. The management pack is an add-on for your current SCOM or HP Ops for that matter.

Replicate Technologies and RDA 1.1

· ·

Just received an email that RDA has been updated. Version 1.1 has just been released and the following changes have been incorporated:

  • Easy wizard based setup – get up and running even faster!
  • Larger scale support – RDA now supports much larger deployments.
  • Highly detailed diagnostic analysis, helping you find and fix problems more quickly.
  • Full support for ESXi

I’m downloading RDA 1.1 right now and will try to right a follow up of my original article “Replicate Technologies Datacenter Analyzer” as soon as I can find some spare time.