Archive for October, 2010

Private Cloud: Build or Buy?

October 9, 2010

I totally forgot about this… a few months back Jo Maitland asked if i was interested in doing a webcast for SearchCloudComputing on the subject of Private Cloud: Build or Buy. Although I do sound like a broken record in places, and I’m not sure if I actually addressed the subject that well (I interpreted the question as build = internal and buy = external, but didn’t actually say that), it’s not a bad listen if you have a spare 30 minutes and you’re a large shop about to embark on the private cloud journey.

Check it out here.


Boot a VM from iSCSI? Yes. We. Can!

October 9, 2010

I was having a chat with someone the other day and we got onto the subject of that most excellent open source project, Etherboot/gPXE. For the uninitiated, gPXE is basically a replacement for the ancient PXE ROM found in pretty much all NICs today, and brings network booting into the 21st century. It gives us the ability to use alternative protocols for the boot media, instead of being restricted to TFTP as the current PXE ROMs generally are. If you want to know more about why this A Good Thing, check out this video.

Anyway, the question was asked if it was possible to boot a VM from iSCSI directly without any involvement from VMFS. Having actually done this quite some time ago, I knew it was possible so I said “yes”, but unfortunately I couldn’t access the memory region that held the answer to the logical next question (how?), and I had to say “I’ll get back to you”.

The only way to do this on physical hardware without using chain loading (ie PXE booting some other program and loading gPXE via it) is to burn the gPXE ROM onto the NIC (I’m conveniently throwing gPXE boot via CD/floppy/USB into the chain loading bucket). Obviously this is not something you would want to entertain with VM’s. But luckily for us, VMware gives us the ability to actually specify a separate file to use for the NIC BIOS! So it’s really quite straightforward, here’s how to do it:

1. Go to the ROM-o-Matic website and create a boot rom with the following options:

2. You should now have a file named gpxe-1.0.1-8086100f.rom.

3. Create a VM with an e1000 NIC.

4. Upload the gPXE ROM file into the same directory as the .vmx file of the VM you just created.

5. Add the following line to the .vmx file:

e1000bios.filename = "gpxe-1.0.1-8086100f.rom"

6. You’re done – you can now take advantage of everything gPXE has to offer.

I tested this out on ESXi 4.1, and it still works like a treat. Why do you need to use an e1000? gPXE doesn’t currently have support for VMXNET3. Since it’s an open source project, perhaps someone from VMware could make that contribution?

Eating Your Own Dog Food

October 8, 2010

This is a post I’ve been meaning to write for a while now, but for one reason or another I kept putting it off. So when Mike Laverick asked me about what subjects I wanted to cover in my Chinwag, I finally got around to talking about it in public. I say in public, because this is something I and many others been saying to VMware behind closed doors for a bloody long time now. And as Mike pointed out during the Chinwag, there’s certain sense of irony in applying this phrase to VMware, given that Paul Maritz is credited with inventing it (or at the very least popularising the saying in the IT world) over 20 years ago.

I’m not writing this post to be inflammatory. Nor do I feel the need to justify my comments any more than what was said in the Chinwag. I just feel that a little more clarity and elaboration is needed – when we started on the topic the conversation was skirting around several things at once, all of which were pretty negative. And although I wouldn’t go as far to label those first 20 or so minutes as “VMware bashing”, I can understand how it might be seen that way. So let’s get that straight – when I say VMware should eat their own dogfood, I mean it constructively. I’m not talking about stuff like vCloud Director 1.0 requiring a database from the least-VMware-friendly company on the planet, or that the vSphere Client isn’t supported as a ThinApp package. I’m talking about something much more fundamental than that. I’m talking about glass houses and throwing stones.

Chinwag With Mike!

October 6, 2010

It was long overdue, but a few weeks ago I finally got around to having a chinwag with Mike Laverick. I say long overdue, because he asked me ages ago and I just never got around to it! This is the second video I’ve been in lately, the other was the very last VMworld TV recording in San Francisco (which ironically also had Mike in it, and Justin).

I wanted to have a post ready to go to elaborate more on the whole VMware / dogfood bit, but as you’ve noticed I’ve been pretty busy lately (ie very quiet on the blogging front). And I guess it’s OK for me to say why… I am very proud to say I am the technical editor for the upcoming PowerCLI book from Al, Luc, Glenn, Arnim and Jon! And let me tell you, it ain’t easy when you’re dealing with masters like those guys.

Anyway, I hope you find the chinwag entertaining / interesting, and big thanks to Mr Laverick for asking me on. As I say at the end, if it wasn’t for Mike I might not have gotten far in this field and even this blog might not have gotten far – he was the first one to give me a shout out way back in the day, and my readership grew exponentially for a while after that. So again, Mike, thanks for everything.