Posts Tagged ‘sVMotion’

Align Datastore Names With VM Names Using Storage vMotion

September 30th, 2009

Does it bug you when the registered names of your VM do not match the folder and file names on the datastore? It can be difficult to identify VMs when browsing the datastore if the folder and file names do not match the VM name. Or maybe the VM names generally match what’s on the datastore but there are some case sensitivity discrepancies. I for one an uncomfortable with these situations. While fixing the problem by bringing the datastore folder/file names into alignment with the VM name isn’t impossible, the process is painful when done manually and requires an outage of the VM.

Here’s a simple trick I’m sure many may already be aware of. I remember hearing about it quite a while ago (I don’t remember where) but had forgotten about it until today. Let VMware Storage VMotion take care of the problem for you. During the Storage VMotion process, the destination folder/file names are synchronized with the name of the VM on the fly with no outage.

For example, let’s say we create a VM with a registered name of “old_name”. The datastore backing folder has the name of “old_name” and the files inside are also prefixed with “old_name”.vmdk, .vmx, etc.

Now we go ahead and change the name of the VM to “new_name” in vCenter. The datastore backing folder and files still have the “old_name” and now obviously don’t match the registered VM name.

To bring the datastore backing folder and file names back in synchronization with the registered VM, we can perform a Storage VMotion. In doing so, the backing folder and files will be dynamically renamed as they land on the new datastore. In this case, they will be renamed to “new_name”.

This solution is a heck of a lot easier than powering down the VM and renaming all the files, as well as modifying the corresponding metadata in some of the files.

Update 9/27/11: As reported by Gary below and validated in my lab, this trick no longer works in vSphere 5.0 with respect to file names within the folder.  As an example, after renaming the VM in vCenter inventory and then subsequently Storage vMotioning the VM, the destination folder name will match the VM however the .vmx and .vmdk files inside will not.  This is unfortunate as I have used this trick method many times.

Andrew Kutz joins Hyper9

February 28th, 2009

This news is a little over a week old but I just found out two nights ago while reading vExpert profiles and it’s definitely worth repeating.

Andrew Kutz is a recently named vExpert by VMware, Inc. and a well known developer in the VMware community. Andrew has authored a number of VirtualCenter plugins, of which the most famous might be his free Storage VMotion (sVMotion) plugin which provides VMware administrators a GUI interface to hot migrate VM storage from one LUN to another. Andrew has received well deserved praise for his work because he makes the lives of VI administrators easier.

Hyper9 is a startup company in Austin, TX that works in the virtualization infrastructure management space, developing tools that automate the management of virtualization in the datacenter. Hyper9 recently secured an additional round of investment funding and it would seem they are totally serious about delivering quality products to the virtualization community in the hiring of Andrew Kutz. What can we expect out of this? Given what I’ve seen from Andrew in the past, I’ll guess the future will be plugin based architecture which I think makes a lot of sense and is probably what the majority of the community wants.

Congratulations to both Andrew Kutz and Hyper9. I look forward to your accomplishments with great anticipation!

Read the official announcement from Hyper9 here.

KB1008130: VMware ESX and ESXi 3.5 U3 I/O failure on SAN LUN(s) and LUN queue is blocked indefinitely

January 19th, 2009

I became aware of this issue last week by word of mouth and received the official Email blast from VMware this morning.

The vulnerability lies in a convergence of circumstances:

1. Fibre channel SAN storage with multipathing
2. A fibre channel SAN path failure or planned path transition
3. Metadata update occurring during the fibre channel SAN path failure where metadata updates include but are not limited to:

a. Power operations of a VM
b. Snapshot operations of a VM (think backups)
c. Storage VMotion (sVMotion)
d. Changing a file’s attributes
e. Creating a VMFS volume
f. Creating, modifying, deleting, growing, or locking of a file on a VMFS volume

The chance of a fibre channel path failure can be rated as slim, however, metadata updates can happen quite frequently, or more often than you might think. Therefore, if a fibre channel path failure occurs, chances are good that a metadata update could be in flight which is precisely when disaster will strike. Moreover, the safety benefit and reliance on multipathing is diminished by the vulnerability.

Please be aware of this.

Dear ESX 3.5 Customer,

Our records indicate you recently downloaded VMware® ESX Version 3.5 U3 from our product download site. This email is to alert you that an issue with that product version could adversely effect your environment. This email provides a detailed description of the issue so that you can evaluate whether it affects you, and the next steps you can take to get resolution or avoid encountering the issue.

ISSUE DETAILS:
VMware ESX and ESXi 3.5 U3 I/O failure on SAN LUN(s) and LUN queue is blocked indefinitely. This occurs when VMFS3 metadata updates are being done at the same time failover to an alternate path occurs for the LUN on which the VMFS3 volume resides. The effected releases are ESX 3.5 Update 3 and ESXi 3.5 U3 Embedded and Installable with both Active/Active or Active/Passive SAN arrays (Fibre Channel and iSCSI).

PROBLEM STATEMENT AND SYMPTONS:
ESX or ESXi Host may get disconnected from Virtual Center
All paths to the LUNs are in standby state
Esxcfg-rescan might take a long tome to complete or never complete (hung)
VMKernel logs show entries similar to the following:

Queue for device vml.02001600006006016086741d00c6a0bc934902dd115241 49442035 has been blocked for 6399 seconds.

Please refer to KB 1008130.

SOLUTION:
A reboot is required to clear this condition.

VMware is working on a patch to address this issue. The knowledge base article for this issue will be updated after the patch is available.

NEXT STEPS:
If you encounter this condition, please collect the following information and open an SR with VMware Support:

1. Collect a vsi dump before reboot using /usr/lib/vmware/bin/vsi_traverse.

2. Reboot the server and collect the vm-support dump.

3. Note the activities around the time where a first “blocked for xxxx seconds” message is shown in the VMkernel.

Please consult your local support center if you require further information or assistance. We apologize in advance for any inconvenience this issue may cause you. Your satisfaction is our number one goal.

Update:  The patch has been released that resolves this