VM /ETC Go Green with Virtualization. Go UGLY Green with vmetc.com.

There are several ways to determine if you have virtual machines with snapshots. Why you would want to know has been covered In various other posts both here at VM /ETC as well as on the other virtualization blogs. It’s so important that the virtualization community has created different tools and scripts to identify and monitor snapshot files for administrators.  So, when I read the post WWoIT - Wayne’s World of IT: Find VM snapshots in ESX/VC I had an experience that Aaron Delp described as “/HEADDESK” (when he commented on my uploading files with the VI Client post).

It may not be the fanciest of methods, but probably the quickest way to find VM snapshots is to use the ls command from the ESX Service Console. By piping the output with grep to find files with the snapshot extension, .vmsn, and using the recursive switch you can scan all the VMFS LUNs visible to an ESX host. That’s so simple it hurts!

To use the ls command to find snapshots do the following:

• Continue reading or Leave a comment... (6)

Lately, I have had several clients and peers ask me how to get disk usage and performance statistics from their current virtual infrastructure of ESX hosts and virtual machines . Some needed data for planning and sizing a new SAN, while others needed statistics for upgrading, adding more disks, or for optimizing multi path and VMFS performance. In one case the customer was trouble shooting poor VM performance issues. Regardless of the objectives there are some built in tools in both VirtualCenter and ESX server that can get this information for you. This post explains 2 native methods:

• Using the VI Cleint to access the Performance data in VirtualCenter
• Using esxtop from the ESX Service Console

I have included plenty of screenshots. As always, click on them for larger views. The rest of this post is in an outline format, but should be easy enough to follow.

• Continue reading or Leave a comment... (1)

Chad Sakac has a great post on his Virtual Geek blog titled The Case For And Against Stretched ESX Clusters. In this post Chad discusses the possibilities of configuring ESX Clusters between 2 different physical data centers. That is, spanning the SAN across a wide area network so that VMs can be vmotioned between sites. The concept is a frequently discussed desire of many administrators, and Chad brings to light some great points for and against this design with specific configuration details about making it work with VMware ESX.

For example, the post explores several options:

• Continue reading or Leave a comment... (1)

Based on best practices, this post is a “formula” for planning and sizing SAN storage for maximum VMFS performance. This is intended to be for all protocols where VMFS volumes are utilized ( FC, iSCSI ) and conservative enough to allow general sizing estimates while ensuring high performance of the running VMs.

WARNING: The storage design resulting from following these recommendations will not be the most cost effective solution. As storage performance generally requires the most spindles (disks) possible and this formula requires as many dedicated LUNs as possible, the cost for storage will be maximized. More often than not, compromises between performance and cost have to be reached that keep the design within the expected budget.

This post is split into 2 sections. The first section lists the VMFS Maximum Performance Rules while the second section uses a 25 server example to walk through the design rules.

• Continue reading or Leave a comment... (8)

This post is a supporting post to the discussion earlier this week sparked by Scott Lowe’s tip on avoiding ESX snapshots when using SAN device snapshots. NetApp’s SnapManager for Virtual Infrastructure (SMVI) is discussed as a solution for streamlining the coordination of snapshots between ESX and the SAN. Luckily, Nick Triantos from NetApp joined the discussion on Scott’s blog with some “under the hood” information:

• Continue reading or Leave a comment... (3)

Duncan over at yellow-bricks.com has posted a very helpful VMware HA troubleshooting tip. Changing the IP-address of an ESX host and HA deals with fixing HA issues that arise after changing the ip address of ESX hosts. In summary, Duncan was helping a colleague that was having trouble reconfiguring HA on an ESX cluster, and even though all the standard steps for resolving the issue were followed the HA feature could not be enabled on the cluster. Duncan was able to to identify that the issue was caused because a HA agent auto-generated file still contained the wrong ip address information. Specifically the /etc/FT_HOSTS file was the culprit.

Read the yellow-bricks.com post for the full details, but I am copying the t-shooting and resolution steps here for my future knowledge base.

• Continue reading or Leave a comment... (1)

Avoiding storage array snapshot pitfalls in a VMware environment is an article and tip published by Scott Lowe for Searchvmware.com. Scott discusses the design challenges and implications of combining the snapshot abilities of VMware ESX with the SAN based snapshot features of storage devices. The tip points out that incorrect configuration of VMware ESX with the storage device could lead to inconsistent and unusable images when trying to recover VMs.

“Because these snapshots are not, by default, integrated in any way with VMware ESX Server, we have to perform a few extra steps to ensure consistently reliable and usable storage array snapshots.”

Read all of Scott’s tip at the link to the article above.

My “2 cents” on this is that trying to configure the combination of the two snapshots manually might not

• Continue reading or Leave a comment... (1)

New Patches have been released for ESX 3.5 / 3i, ESX 3.02, and ESX 3.01. Information from the email notifications I received are copied in this post. Looks like monthly patching has become a reality for VMware. That’s the ultimate proof of success, I guess. If it’s a popular product the chances of it being exploited are increased exponentially. Make sure your Update Manager server is working properly …..

• Continue reading or Leave a comment... (0)

VMware and Tripwire have released a free tool that analyzes the configuration of ESX servers and compares the results against established best practices. ConfigCheck is a free utility that downloads to your desktop where you can easily assess whether your VMware virtual infrastructure is properly configured for security. According to Tripwire’s download page the tool is available for both Windows and Linux. Tripwire Configcheck was developed as a no cost introduction to the fully featured and licensed version of Tripwire Enterprise.

Both VMware and Tripwire have information about the free product on their websites. The following information from both sources provides a good summary about what the tool can do.

• Continue reading or Leave a comment... (0)

I ran into an issue today with the open console command from the VI Client. I was already connected to a stand alone ESX3.5 host. I had just finished creating a new VM, configuring the virtual CD to use the OS install media .iso, and I had powered on the new virtual machine. When I right clicked on the VM and selected “open console” I got the following error message:

“error connecting: can not connect to host x.x.x.x: a connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.”

Once again the VMware Communities forum came to the rescue.

• Continue reading or Leave a comment... (5)

A common issue after installing ESX servers that do not have all their NICs cabled is that you can not ping the host. For example, say you have an ESX host with 6 1GB network cards - 2 on board and 4 PCI. You would think that cabling the 2 on board cards would cover network connectivity. Unfortunately the order that ESX recognizes the NICs is not determined in a logical, expected order such as on board and then PCI cards. In fact, if you know how ESX determines how to order the network cards please comment and let us all know! In the meantime, here is how to use a few esxcfg- Console commands to make sure the cabled NICs are linked to the vSwitch that has the Service Console PortGroup (where the ip address is assigned).

• Continue reading or Leave a comment... (2)

To clone a virtual machine with VirtualCenter you have to power off the guest, but what if your next maintenance window isn’t any time soon, you can’t afford to schedule the outage, or you just need a copy of the VM during normal business hours? Did you know that making a copy of a running, powered on VM is possible. At a high level the process requires a snapshot to freeze the VM’s original disk which in turn allows you to clone the frozen disk. This is essentially the way VCB, vRanger, or any of the live VM backup products work. Therefore, cloning a powered on VM can be accomplished with a little Console command magic.

I want to acknowledge that researching this method was inspired by the VMTN Virtualization Roundtable Episode 1 Podcast’s coverage of snapshots. Specifically Eric Siebert mentions that using VMware Converter as an alternative to committing snapshots is not the best option and offers the idea of using vmkfstools to do the job.

• Continue reading or Leave a comment... (2)