Oct 25 2008

Wholesale High Availability

Alan just coined WholeSale HA. The idea of rebooting a whole virtual machine rather than just failing over 1 service.

He wants to have the best of both worlds in 1 framework, he however doesn't specify what parts he likes from the WholeSale HA setup

Yes you want to use it coupled with hardware predictive failure analysis tools. In order to achieve Higher Availabilty, but I don't think the WholeSale HA part is real HA.

WholeSale HA isn't going to be fast enough for most of the business critical environments.
You simply cannot afford to reboot or even boot a full machine and the related downtime that brings for your service.

So yes a best effort combination, but with a strong focus on the application state would be preferred. WholeSale is a good start .. but it's definitely not where you want to stop.

Jun 03 2008

Xcerion, please abort your mission

So back in early may 2007 (yes 2007) I signed up for the Xcerion Beta program, I`m always interested in the next new Internet OS etc so I tought it was a good idea to give it a try.

In December of that same year I got a message stating that I made it to their Beta cloud. Their mail stated

This is your invitation to participate in Xcerion's XIOS/3 Beta program. You are one of the first in the world to get access to XIOS/3.
We currently only support IE6+ browsers. We are working on adding Firefox support (high priority).

Obviously didn't sign up ..
In April when I got the invite mail for the 4th time .. I replied to the Xcerion folks ..

As I am a Linux user .. I need firefox , since your initial mail
december 21st last year you say that Firefoxx support is high
priority ...

Their reply:

We have made some great progress on the Firefox version. This is the most
complex and fully featured cloud OS available, which makes porting more time
consuming. We are also constantly adding a lot of features. Xcerion is also
considering doing a native Linux version :)

Today I got yet another mail from them guess what still isn't supported ?

We currently support IE6+ browsers. Rest assured that we are working on adding Firefox support (high priority). The Firefox support will also enable usage of icloud on Mac and Linux

It's time to give up guys .. you lost the battle.

Nov 17 2007

I hate it when the marketeers take over

Tarry has an overview of the commentaries about Oracles latest Virtualisation announcement.

Two things hit my brainwaves, First ,seemingly Larry is claiming that his Xen package is better than
the others since he supports Live Migration and all the others don't. I don't know where he gets the idea.. I have to admit I don't remember which year it was .. but it was somewhere in december that I first starting with Live Migratiion of Xen machines and it was also on a CentOS platform. No fancy gui, no hardcover manuals that had it all documented. But fast and seamlessly working live migration, ready for everybody to use.

Second one is he claming that since Xen was re-engineered by Oracle to be faster than the competition.
The way you read it there is that Oracle took Xen, modified it then started redistributing it.
Is that really what happened ? Are they redistributing the source, or are they violating the GPL ? Coz if they are
redistributing the source everybody just got a faster Xen and if they aren't ..
I don't know but there sure is room for rumour here. Or is this just a bunch of marketing people and IT journalist that are mispresenting the facts. Fact is that one needs to spend lots of time verifying the facts of stories one read on the internet today.

I`m also seeing people crying that Oracle is finally stepping to the open source side.. .. I`m wondering on which planet they have been living.. Oracle has been supporting different Open Source products for ages already and they even are the owners of core components of typical daily used packages, so where do those authors get the idea that Oracle is finally stepping over ?

Tonight I don't have time to go and hunt back the original sources and see who actually said what . Honestly I don't care that much about Unbreakable, Last time I tried caring was when one of my european customers was interested in it, and no one at could help me . It's Like Dell shipping Ubuntu.. not on this part of the world.. and sadly it's also like the OLPC .. Give one Get one only on the other side of the Ocean.

It's all good marketing .. until you actually want to get it .. :(

Just give me the source code .. then I don't have to sit trough presentations from marketing people that can only read from spec sheets for some product , but fail to read the fine print and leave me disappointed again ...

Oct 17 2007

Virtual Machine Replication

I don't know on which planet I have been for the past couple of years , days or hours but since when do
VMware’s Vmotion, XenSource’s Xenmotion or Virtual Iron’s Virtual Iron support Replication ?

Live Migration yes, but Replication , No.

I discussed this kind of technologies with Mark and Vincent , Moshe and others already a zillion times.. Continuously mirroring or realtime replication of a virtual machine is really difficult to do. And I haven't heard from a working scalable solution yet .. (Shared Memory issues such as we had with openMosix still are amongst the issue to be tackled)

Live Replication would mean that you mirror the full state of your virtual machine realtime to another running virtual machine. Every piece of disk/memory and screen you are using has to be replicated to the other side of the wire realtime. Yes you can take snapshots of filesystems and checkpoints of virtual machines. But continuous checkpointing over the network , I'd love to see that.. (outside of a lab)

So with a promise like that .. our good friends the CIO will be dreaming and the vendors will be blamed for not delivering what was promised to them.

But on the subject of using just Live Migration features as an alternative for a real High Availability solution , I know different vendors are singing this song, but it's a bad one.

Using Live migration in your infrastructure will give you the opportunity to move your applications away from a bad behaving machine when you notice it starts behaving badly, hence giving you a better overall uptime. If however you don't notice the machine is failing, or if it just suddenly stops working, or if your application crashes you are out of luck.
Live migration won't work anymore since you are to late, you can't migrate a machine that's dead. The only thing you can do is quickly redeploy your virtual machine on another node, which for me doesn't really qualify as a Clustered or HA solution.

Real HA looks at all the aspects of an application, the state of the application, the state of the server it is running on and the state of the network it is connected to. It has an alternative ready if any of these aspects fail. Session data is replicated, data storage is done redundantly and your network has multiple paths. If your monitoring decides something went wrong another alternative should take over with no visible interruption for the end user. You don't have to wait till your application is restarted on the other side of the network, you don't have to wait till your virtual machine is rebooted, your filesystems are rechecked and your database has recovered no it happens right away .

But Virtual Machine Replication as an alternative for HA ? I'd call that wishfull thinking and vapourware today

Aug 09 2007

Dell's Linux offer in Europe : still vapourware

Is Dell abusing with its Linux offer ? - lefred's own blog ;-)

Yes Fred, it's pure marketing, I talked to chatted with an online Dell sales rep earlier this week because I was looking into buying either an Ubuntu Dell Laptop or a laptop with no operating system. She had to check around but none of the above was available in Europe , let alone Belgium , she also tried the UK, all this after Dell is making big announcements in the US.

Oh and did I mention.. the laptops they offer in the US aren't even close to what I'd want ? A decent screen to start with .. not some 1024x768 Max thingie ..
I'd rather have them not selling a distro and just offer the NO OPERATING system option with all their products rather than a minimal laptop configuration that I don't care about.

Aug 08 2007

Dell plans to embrace virtualisation

Dell plans to embrace virtualisation

LinuxWorld, Dell CTO Kevin Kettler let slip that the company plans to sell machines that will boot a hypervisor from flash memory.

Xen on Flash ?

Next step, let's kick the bios out.