Archive for the ‘VMware’ Category

VCP4 Exam Post Mortem

Sunday, November 22nd, 2009

Long story short, I passed.

Exam was fair, tougher in my opinion than the VI3 exam which is a good thing since I managed to pass that exam without ever having used ESX, Virtual Center, etc outside of the required training course. There were a lot of good questions in the VCP4 exam that require you to actually know how to use ESX, vCenter, Update Manger, etc and not just be able to recall facts or figures. That said, it’s well worth studying the configuration maximums and install, administration, upgrade guides, etc as many questions also come from there. I heard there was less memory test type questions (like configuration maximums) in this exam but I definitely got a few in my questions set.

I was time poor in studying for this exam and really would have liked more practical knowledge of vSphere before going into it. The study resources I previously posted about were brilliant. Simon Long’s blueprint links and Forbes Guthrie’s vReference card are outstanding resources and I found myself continually going back to them. Know the exam blueprint and study what it indicates you should study.

But most importantly, to understand vSphere and what the exam wants you to know, you need to use it. So download ESX 4, vCenter, Update Manager, VMware Data Recovery and get them setup in a lab and use the 60 days of evaluation period to really understand how it all works. You might not be able to do everything (not everyone has FC, iSCSI and NFS boxes lying around), but most features you can get a good overview of by setting up a single host or even better two virtualized hosts.

VMware vSphere ESX 4 Update 1 Released

Saturday, November 21st, 2009

On 19th November, VMware released vSphere / ESX and ESXi 4 Update 1. It also comes along with the release of updates for VMware Data Recovery 1.1 and VMware CLI tools for vSphere / ESX 4.

VMware ESX 4 Update 1 Release Notes
VMware Data Recovery 1.1 (VDR) Release Notes
VMware vSphere PowerCLI 4 Update 1 Release Notes

VCP4 Upgrade. Tick Tock.

Friday, November 13th, 2009

Since VMware are allowing currently certified VCP3’s to do the VCP4 exam before December 31, 2009 without having to take the Install, Configure, Manage course AND are offering a free 2nd shot [link], I have booked in my exam. Giving myself about 2 weeks to study the new stuff in vSphere / vCenter Server and refresh everything VI3.

Study will be based around the following:

Beyond that I’ll get some practical time in running up ESX hosts, building vCenter, using Update Manager, trying to test as much as possible of the new features (vMware FT, Distributed vSwitches, DPM, etc).

VMware ESX – Another Snapshot Fix

Sunday, October 25th, 2009

As an update to this post, a snapshot chain could also become corrupt if for some reason the .vmsd file (snapshot definition file) does not get updated when a snapshot is taken. The result of this can be seen by running:
vmware-cmd <vm-name>.vmx hasnsapshot
and it returning blank, or by checking Snapshot Manager in Virtual Center and it being blank, however you know snapshots exist because when you check the VM’s .vmx file, it is referencing snapshot delta files not the parent vmdk.

The .vmsd file’s purpose is to maintain information about the snapshots on that VM. It is read by Virtual Center to get the snapshot name and chain details. It is also read by vmware-cmd in the above command.

The solution is is to first confirm that hte current snapshot CID / pCID chain and fix that if it is broken. Then remove the .vmsd file. Next, create a snapshot on the VM either through vmware-cmd or through Virtual Center (it’s best to do this logged into the ESX host directly rather than Virtual Center because we will also remove it from the host). Next, check the snapshot chain either in Virtual Center or using vmware-cmd, this time you should see hassnapshot = 1 and the fiull, correct chain in Virtual Center. Finally, if the chain is restored correctly, remove the snapshot chain as you would normally.

VMware ESX: Renaming a Virtual Disk

Sunday, September 20th, 2009

A VMware virtual disk is made up of two files, the disk descriptor (<name>.vmdk) and the disk content itself (<name>-flat.vmdk). Using Virtual Center, you can move virtual disk files around (i.e. folder to folder), but it will not let you rename them. To do this you have two options: mv or vmkfstools.

Using mv:
SSH to the ESX host, cd to the location of the virtual disk. Oh, if the disk was attached to a VM, that VM needs to be powered off. Type:
mv oldname.vdk newname.vmdk
mv oldname-flat.vmdk newname-flat.vmdk

Next, need to edit the descriptor file so it can locate the disk (you can use vi, pico, nano):
vi | pico | nano newname.vmdk – Locate the old name in the file and edit to match the new name. Write out the file.

Using vmkfstools:
vmkfstools can rename the files and update the descriptor all at once (command is all on one line):
vmkfstools -E /vmfs/volumes/path/to/oldname.vmdk
/vmfs/volumes/path/to/newname.vmdk

Finally, if the disk was attached to a VM, back in Virtual Center (or by editing the .vmx for the VM) edit settings for the VM and point it to the newly renamed virtual disk. You can then power on the VM.