Implement Virtualization for Application High-Availability

Alone, the term ‘high availability‘ does not mean your application never goes down, that would be ‘always on‘, but highly available applications require some simple things you might already have within your infrastructure. If you run a virtual environment, then achieving application high availability is just a few clicks or scripts away, if you choose to roll-your-own, but there are also products that one can purchase to do similar things such as Symantec’s Application HA package, a scaled down version of Veritas Cluster Server. But if what you need is “protection right now, today” then you can get started by using built-in technologies for a given hypervisor.

HA Process

Regardless of type of hypervisor you can enable guest failover, moving, takeover, replication, etc and can be done through a series of different steps and mostly involves mild scripting.

For all VM hosts there is some kind of scripting hook that can be used to achieve the following series of steps:

  1. Verify whether or not the Guest VM is on-line and booted
  2. Verify VM related settings and store/export them if needed
  3. Control the VM (quiesce, freeze, power-off, shutdown, etc) to prepare for movement
  4. Backup or copy the VM to new storage or a new host
  5. Restore VM related settings/import them if needed
  6. Spin up the VM
  7. Verify whether or not the Guest VM is on-line, booted, and active on the new host or location

These are the basic steps that can be achieved through scripting either by utilizing APIs for each hypervisor or manually performing each and every step through the use of standard OS level scripting automation. (logging in as a user, executing a power off or other set of commands to prepare the VM and logging in after the VM has been powered on again to validate it is up and running properly and start applications)

Developing this type of capability can be pretty easy but does take some time so be aware of any tools you might need but simply because the VMs exist in containers able to be moved pretty much anywhere on the same network segment or route, that is all that is required so long as the guest VM can run on the target platform. You of course may need to integrate your host monitoring software in order to execute the scripts automatically, but if you don’t have that level of monitoring in your environment you can script that too and all with assets you already own. The main investment is time and testing to ensure the environment is sound after a move/failover.

Express your thoughts and leave a comment!



First Look: Flipboard for iPad

There are already lots of opinions on places like iTunes for Flipboard for iPad. If you were looking at some of them in the first week, users were pissed. I was so freaking excited to get “my” content on my Flipboard, I just had to wait a while. So after about 3 days i was finally able to get it all setup and it was over the weekend, so the folks who developed Flipboard were indeed working on adding capacity. (hey, I used to be a systems architect for a similar model, I know what it takes, and so far, so good for you guys.)

Anyway, let’s talk about what I think Flipboard can do. I think the best way to describe Flipboard is that it is a media aggregator. It is completely configurable with up to 9 sources which you then flip through to read much like any digital magazine and it even has a page flip animation which overall, is nice, simple and makes good use of the iPad screen. Reading can be done in landscape or portrait mode. I will point out that the sources are a bit limited but Facebook and Twitter feeds are among the top possible choices so getting used to seeing your own media inside Flipboard is pretty easy and quite interesting given the layout of the data displayed. You can also easily repost to any configured services or forward/browse stories and links to share something which crossed your path.

Now for what Flipboard doesn’t do. There is no reload button, so when trying to browse on a slower connection, it can certainly be frustrating. And by slower, I don’t just mean 3G vs WIFI, but more like 3G vs Edge. Edge seems to be the killer but without a reload button, and some kind of Edge aware caching, I don’t know if the reload button would help, but I still feel this is necessary.

Another thing is the current lack of RSS support, but the folks at flipboard are currently working on , or are about to be, that feature. There is also no text only or low bandwidth mode, so speed, even across 3G, means there may still be some waiting depending on the number of images being loaded. There are also no groupings of data that can be configured. You’re stuck at 9 configurable inputs and that’s it. One thing it does do though is that Flipboard not only aggregates the data you want it to, but you get to share and reply to things you see. I’m just pointing that out again though I mentioned it earlier, I think this aspect needs to be reinforced. It’s not just a hews reader with a pretty face, though it does have one of those, it is a communications application to help us manage our social data. So head on over to iTunes and grab yourself a copy and try it out and en give feedback to the flipboard folks as they sure seem to be listening (@flipboard on Twitter). Likewise you can check out the feedback forums and tell them what you think.

Overall a great app with a lot of potential and great built-in feeds which can be replaced with any protocol they support as well as preconfigured feeds which you may also like. I do recommend this app, and have yet to see anything quit like it in the app store to date. I just hope they keep the pace with the user issues and balance that with good clean technology as they continue to work through features and bugs. Don’t forget, if your trying it now, you’re on the bleeding edge of this technology so understand there will be changes and issues along the way. So be sure to utilize their feedback forums!