Friday, 5 July 2013

LonVMUG, vBeers and a vCurry!

Wow! I nearly didn't make it. A particularly "late one at the office" the night before saw me get to bed just short of 4am, with the prospect of a couple of hours train journey for a 9 something LonVMUG start. So, forget all about starting the day at 6am then.

The late start to the day turned out to be particularly gutting as the Twitter chat around the event pretty much ceased whilst Frank Dennerman was doing his presentation, so I was pretty miffed that I didn't catch it live as it was obviously getting everyone's attention! Fortunately, this was the first LonVMUG where all the presentations from the day were uploaded to the Box  before the event was over (wonders will never cease!) so I will be able to review this over the coming days.

At least I was able to fill out the LonVMUG attendee survey on the train up to the event, so I felt like I was taking part even before I arrived. Very funny survey by the way. I eventually got to the Chamber of Commerce just in time for lunch - and just before everyone else got out of their presentations, so I had first run at the chips. Result! Pretty good food at these things - and this time, Cake. Not as good as my wife makes though (In case she somehow reads this).

Pretty much the first person I saw whilst I was stuffing my face was Dale who'd been in setting up XenDesktop for us only a week or 2 before, so we were able to share a bit of a chat about how that was going, my 1 user is very happy, it seems. Then a run around the vendors to pick up the info and enter the draws for the swag and it was time to go and and actually learn something.

First up for me then, was the Atlantis Computing's ILIO sponsor preso, which was something totally new to me.  Turns out that the biggest VDI deployment in the world runs on this, so it has to be worth considering. If you want to take ESX host memory and re-present most of it back to your host as disk for your VDI estate, with dedupe and memory-speed / IOPS advantages, then this is probably the tool for you. Being VMUG this was all about VMware, but they cover Citrix too. Slick presentation, a live demo and a reference customer to talk about it too. nice!

Then on a VDI continuation tip, it was time to listen to the Xtravirt boys talk about a 4000 seat VDI experience. Xtravirt are strong supporters of the LonVMUG, they've had someone doing a talk at every VMUG I've attended and they're usually informative and entertaining. Glad to say that Seb and Grant didn't let us down, I learn a few things from both them and the audience, which was just what I wanted.

Finally from an event point of view, was Julian Wood's VDI Roundtable. There's a common thread here, no? That put about a dozen of us in a room behind a closed door to talk anything VDI. We had a mix of VMware, partners, end users which really helped. This was an excellent hour and I felt that this could have gone on for a lot longer than it did, as we'd only really just got going when the call came to close up. Slightly reassured that I was doing the right thing with VDI, I headed back off to the main hall with everyone else for the wrap-up.

As previously stated, the wrap had the announcement of all the sessions being available and an announcement about the VMUG Advantage offering was also made. The survey results were rounded up, LonVMUG having a Mike Laverick fascination is about all I can remember from that. Then the giveaways. Win!! I get granted a year subscription to the aforementioned VMUG advantage. As one of the very small nmber of people in the room who actually HAS one of these, it seemed the right thing to do to give it back, but then I realised I only had a few weeks left, so it's mine to keep. So definitely worth getting out of bed. I'll do a blog post on VMUG Advantage at some point, as I really like it as a concept.

Then vBeers, the bit which seems less optional every time I go, you learn as much at the "aftershow" as you do at the main event. With well over a dozen vExperts at this VMUG, how could I go wrong? Good times, plenty of chat, a few beers and a round up for a vCurry as well. Very good. But I got home late, vLate, vTired etc. next up the UK VMUG in November, I hope to make that this year.

Top 3 terms you may not know, but wish you'd invented...
#HansFree
vLady
vMuggle

Thursday, 6 June 2013

mbralign for NetApp filestores

Migrating VMs to a NetApp filer is all well and good, but there's a disk alignment issue to get past once those migrations are done, otherwise your expected performance will be seriously impacted.

You should use the version of the mbralign tool included with the latest NetApp Virtual Storage Console (VSC) to check VMDK partition alignment. There is a version of mbralign for ESX hosts and one for ESXi hosts and you're given the option to select the correct one at download. Grab the VSC from http://support.netapp.com/
 
The mbralign tool is effective on both  -flat.vmdk and fixed .vhd files - as long as they are partitioned using an MBR partition table, rather than GPT.
 

To scan for misaligned vmdk's from an ESX host console, change to the directory where mbralign is installed and enter the following command;
./mbralign { --scan all | filename }
 
The --scan all option scans all -flat.vmdk files, whereas entering a <filename>-flat.vmdk scans one file.
 
The command displays whether the VMDK partition is correctly aligned, you will see information about the file(s) ending with Aligned: No or Aligned: Yes

Before you remediate - consider this relatively long list of caveats and warnings;

For ESX clusters, you must run the mbralign program on the ESX host where the VM is
currently registered. For NFS datastores, the mbralign program cannot detect if the VM is powered down if the VM is running on another ESX host.

Running the mbralign program on a VM that is powered on can corrupt the VMDK. You must then restore the VMDK from the backup created by mbralign.

When you use the feature to preserve Windows drive letter mapping, you start with the VM powered on, and mbralign powers it down after collecting drive letter mappings.

If you do not want to shut down the VM, take either a Data ONTAP Snapshot copy of the volume containing the Datastore LUN or NFS Datastore, or clone the VM in question, and then run mbrscan against the cloned copy.

Be aware that mbralign can take a number of minutes per gigabyte of storage to align files.

Consider VMware vCenter Converter as an option to align VMs if you cannot power machines off for long.

Remediation Steps

  1. Remove any VMware snapshots from the VM that is to be realigned. You can also think about removing any other drives that don't require alignment from the individual VM.
  2. For Linux VMs, and Windows VMs with only a C:\ drive, shut down the VM. For a Windows VM with multiple drive letters mapped, the VM must be running so that mbralign can collect the drive letter information before it shuts the VM down.
  3. On the ESX or ESXi host console, change to the directory containing the .vmdk file for the VM.
  4. Enter the following command: path/mbralign name.vmdk
    path is the path where the mbralign program is installed.
    name is the name of the VMDK file being aligned.
  5. If prompted, enter yes for a Windows VM to automatically collect and restore drive letters. Enter the Windows Administrator credentials for the VM.
    The VM is automatically shut down after the drive letter information is collected.
  6. When prompted Are you sure that no snapshots/linked clones exist for this vmdk? Enter y.
    Attention: The use of mbralign on a VMDK file that has a snapshot or linked clone associated with it can result in unrecoverable data loss or data corruption.
  7. For Windows guest operating systems for which you are not using the drive letter restore feature, restart the VM and verify that the guest operating system boots successfully.
  8. For Linux guest operating systems using the GRUB boot loader, reinstall GRUB before restarting the VM.
  9. After verifying the VM has booted and is operating correctly, delete the backup files created by mbralign. These files are saved in the same directory as the .vmdk file and have names ending in -mbralign-backup.

 

Friday, 24 May 2013

VMware vCloud Hybrid Service

Just as I was thinking about starting this blog site, along came the public release of VMware's entry in to the cloud space, vCloud Hybrid Service. I think that VMware first started telling me that I was on a "Journey to the Cloud" at VMworld way back in 2008. I guess I have been meandering a bit since then as I am not sure that I have gone too far on that journey. Admittedly, I have a lot of VMware experience within a pretty large company now, but I would not go so far as to say I was at the bleeding edge of private cloud technology!

The vCloud Hybrid Service was launched publicly on May 21st and is aimed at people like me, those people and companies who have reasons why the public cloud has just not been adopted. This new offering is definitely right up there on message with what VMware are saying this year, as I keep hearing that they want to "simplify IT, again". From a raw, external perspective, without delving into pricing models and availability, this idea seems quite attractive. There's been a fair amount of work behind the scenes already - the service was announced back in March and there's a number of reference sites out there already, as those who've seen the launch material will know.

Now, I have no vast cloud experience at this point in time and so I have no real sense of where this offering is positioned, but then,that's exactly what VMware are looking for. VMware want to appeal to those folks who leverage vSphere in their own datacentres and just want to spill out into the public cloud for a while or have a pressing need to expand quickly to take on an increase in demand for workloads, without having to have a retooling exercise, change IP addresses, learn a new interface or, well, anything.

However, there's a company that offers pretty much all of that already, a rather big box shifter called Amazon, whose AWS service is based on VMware vSphere, is marketed on its simplicity and charges only for the time you use it. vCHS is starting out of 4 locations in the US, and is slated to expand in to EMEA in 2014. I for one will be watching with interest to see how this competition develops.

Why Now?

Why start a totally new blog about virtualisation topics at this late stage in the game, when there's already a whole host of excellent sites out there? Sites I use myself regularly, too. I've shied away from this before, thinking that I will find it difficult to be on top of the game enough to provide useful content to complement existing sites.

Well, there's this thing... The other day I found out about a website called CloudCred, which is basically a VMware backed educational website, which incentivises its members to develop knowledge and build collaborative teams via gamification. You perform tasks, learn stuff, download or implement stuff, spread the word about other blog posts or advances in the field of virtualisation (Well, VMware's virtual offerings, and selected partners at least) and you are awarded points. You're encouraged to form teams and perform team tasks.

That's all simple, fun stuff, nothing really new there, but it was just one more incentive for me to start blogging around virtualisation as, well, I'd get points for it and we all know points means prizes. Pens, pins, t-shirts, that kinda promotional gubbins. I'm a sucker for free stuff.

However, that was not all it was for. Maybe I have something useful to say occasionally, maybe I will learn somthing in the process huh? It should be an interesting ride, regardless.