Posts Tagged: Amazon AWS

Applications / Recovery — 1 Comment
8
Apr 10

vKaiser.com

I’ve been neglecting the blog for a while and feel sorry about that. The spring has been busy and will most likely stay like that, some bachelor parties and weddings and I am also going to be a dad in the beginning of June! The boy is already kicking strong!

But I also have some new cloud related things to tell you about. Since the blog isn’t exactly driving traffic too much and I had some free CPU resources, I started a new project, vKaiser.com, which is a more Web 2.0 oriented site. Well, an imitation of YouTube but with heavy connections to social media sites like Facebook and Twitter. The site is by no means ready, but you are welcome to check it out – with Firefox. IE7 is ok too if you are not on compatibility mode. Interesting things to mention is the storage of the videos and thumbnails in S3 and the possibility to use CloudFront too.

And just to make this post a bit more cloud related and not just pitching my new site, a short story of what happened during the development at one point. As said, I had the Facebook Connect module as well as the Drupal for Facebook (yes, I ended up running Drupal as the CMS system) module installed but I had not enabled the Facebook Connect module since the Drupal for Facebook does essentially the same thing of connecting with your Facebook credentials. Or should do. I had and still have problems with the module as it forwards to a page which can’t be found but still after a few refreshes actually logs in. Anyway, I did go and enabled the Facebook Connect module while Drupal for Facebook had the same functionality enabled if another module would work a bit better.

Sure enough, after enabling the module I was watching a white browser screen with an Internal Server Error 500 with no access to the admin interface at all. What to do then? Should I mess with the database? Remove some modules and run update.php? Well, could not even access the update page. Luckily, I was running the site on an EBS based image! I had a week old (yeah, a bit old, but I did not mind) snapshot of the volume so all I had to do was to get the static files out from the bad volume, create a volume of the snapshot, shutdown the instance, detach the bad volume and attach the new volume. Boot up. Reboot had to be done too for some reason before I could see the log from AWS EC2 console. Reattach the elastic ip, copy the static files and I was back in business. Restore time below 10 minutes.

I love EC2.

Amazon AWS / Applications / Cloud Computing — No Comments
11
Feb 10

Dear Amazon, please make DevPay available in Europe!

So you have your great new application utilizing all the awesomeness of Amazon AWS? How you gonna sell it?

There are vague definitions of what is a cloud service and one of the prerequisites was that you could buy the service with your credit card and to pay only for the resources you use. Amazon DevPay allows developers to sell their AMIs (with application installed), all you need is a business in the US.

There are two ways how you can use DevPay: through AMIs you have built with the service installed and also by selling an application which uses S3 as the storage location. It’s a really good start, but still lacks a few things, like if you actually would like to provide high availability for the client who bought your AMI, the client will have to roll their own solution to achieve this. I bet in principle not many clients are willing to do that and would just like the application to be available.

When I think about this dilemma, a solution might be to have some kind of a root AMI which a customer would buy (and pay by the hour like crazy). This would then take care of the availability of the service by seeding new servers which are members of the application through some very wicked autoconfiguration. Actually, Elastra does almost this as their product allows the user to define architectures and then deploy them to Amazon. In principle, it would be possible to have an Elastra AMI with some configuration inside which the client could then deploy, but it does sound like a hack and not really something you could sell as a product. By the way, the Elastra’s product looks great for defining and deploying architectures at least internally within an organization.

The seeding of an application from a root AMI might make clients able to buy a redundant application and not pieces of it. So far, though, this is just a beautiful dream since the DevPay is not available in Europe so it isn’t possible to start with even the simplest model of serving an AMI of your superduperapp for the public. That is, if you don’t implement billing yourself. If I’m not totally wrong, the billing API is not public which makes rolling out your own solution impossible (you can’t either put limits based on usage charges in your account due to this reason).

I would be willing to adjust the definition of a cloud service regarding the pay by the hour and order by credit card before DevPay is available in Europe.

Amazon AWS — No Comments
15
Dec 09

Unexpected Outage

The site went down today for a few hours and the worst thing is, it was sort of my own fault. The last time I was playing with booting from Amazon EBS I must have made a mistake when detaching volumes from the (wrong) instances. Thus, the incident was caused by the EBS volume not being attached. When I was trying out that EBS booting the one and only EBS volume which is attached to this EC2 instance had the “Attachment Information” as “busy” and not as “attached” which seems to be the standard status of a well working volume. I probably detached the volume and the status changed to “busy” state.

I remember wondering what that “busy” meant at that time. Now I know.

It should go without saying that this status information of “busy” is really, really uninformative. How about “detaching” instead when a user wants to detach a volume? And why did it take about one and a half weeks to detach? Is there a log somewhere I really did detach a volume? The lesson learned from this incident is to act if your EBS volume goes to “busy” state. All might work fine for a while but be warned, it will detach at some point. Also, it would be really nice if there would be some abstraction layer in between the real names of the volumes and instances and the ones available to customers. With this layer a user could add more descriptive names to instances or what ever objects there are. Or then really start using different accounts for development and production stuff… Really.

Applications / Cloud Computing — 1 Comment
12
Dec 09

Deploying applications instead of Virtual Machines

I’ve been thinking the relationship between operating systems and the reason why they exist – the applications. How does PaaS fit into the future of computing or is IaaS just a stepping stone to a world without the traditional one server, one application approach?

Having a background with enterprise IT, I know something (but not much) about deploying applications. Many of them are multi-tiered, the usual being front-end application servers with back-end database servers. Some may have a load balancer in front of the application servers. Thus, there are a few different roles a server must fulfill to deliver the service to a customer using the application these servers in whole produce.

How do you set up an application? It depends about the requirements of course, but basically there are some usual things, at least if you narrow the selectable services. VMware got an idea to bundle a few virtual machines into a vApp which can then be deployed. I have not personally used those, but they seem like an interesting concept. They do work in a bit different way than how an AWS instances would work since with VMware you have the luxury of for example vMotion taking care of VM migration in case the host dies… Giving there is a VMware HA cluster in place. Hiding the complexity this way sounds fantastic! I love it. I do want the same in Amazon AWS!

There has to be a way to group things in Amazon AWS. There are a few tools such as RightScript and Puppet which provide a way to move from a specific AMIs to specific scripts which produce a certain kind of servers. Using these scripts it should be possible to deploy a full application with various components. Puppet also makes it possible to update a class (with Puppet the servers may belong to a class, maybe clasess) of servers to have for example the latest resolv.conf file. Sounds nice! Essentially, this sounds a lot like Microsoft SCCM but for UNIX like operating systems.

How about a future where a business owner could just browse to an IT webstore, select a CMS installation with a rough estimate of usage and the system would just produce it by running the scripts in the backgroud? Or upgrade an existing system? How many IT admins would lose their jobs?

Amazon AWS / Cloud Computing — 1 Comment
6
Dec 09

Booting from Amazon EBS

Amazon has announced a new feature of booting instances from EBS volume. This feature changes radically the way how AWS instances can be preserved if compared to the traditional volume bundling and uploading to S3.

Though this all sounds nice, it isn’t really too easy to convert existing instaces to boot from EBS. All previous instances boot from the local instance disk. Amazon AWS management console indicates the location where the instance boots with the Root Device Type column. Previous instances have the root device type as instance-store while EBS images have the type as ebs.

To get started with the EBS images, there are a few images from Amazon which are useful as a base image. It was really easy to just boot one of them and mount one EBS volume which contained a snapshot of the database and the www root. Installing basic LAMP stuff, changes in httpd.conf and my.cnf to point in the EBS volume and the AWS instance which boots from EBS was ready. I could now create snapshots of the system in minutes and also shut down the system when I don’t need it and thus not get billed for the instance. Awesome! The snapshot also had the EBS volume snapshotted which was mounted to the instance.

The EBS image feature is likely to open a wide range of new applications and really change the way how an elastic service is been constructed. Basically, a member of a pool of web servers can now be created in advance and just turned on when there is a demand to use it. Of course, it first must update itself to be on par with the other pool members.

I am not really sure if it was my old lap top which I used to work with the EBS images or what, but the AWS management console was painfully slow in responding, especially when using Firefox. And when using IE, I did not get anything else in the pop-up window than the button to create the snapshot:

createImage

Firefox, though really slow in responding, gave the option of typing the name in the required field. Also, if you create EBS image and then decide to get rid of the EBS image, you have to delete the AMI first, otherwise the management console will complain that it’s in use.

I have yet to decide should I go with the instance-store or EBS with my instance. It will add something to my costs of running my site in AWS, but that shouldn’t be too much. I find a lot more benefits with EBS than running in instance-store, but then again I fear getting lazy in responding to possible threats of instances going down and disaster recovery.

Pauli Haikonen

← Older Entries
Newer Entries →