Large companies and start-ups are comfortable in the world of Linux servers but most small companies are Windows to the core.  This may not be “right”, this may not be how it “should be”, but it is so.   Even within large companies, departmental computing is largely a Windows only enclave, with MS Office (and Excel in particular) as the backbone and MS SQL Server as the database of choice (or is that, no choice).

The other interesting thing is that my fear that EC2 SQL Server Standard instances would be licensed as per Oracle has not come to pass (Oracle while making a “big thing” of their recent EC2 cloud conversion, still insist on traditional licensing for EC2 database instances). SQL Server Standard is available on a pay-as-you-go model, brilliant!.

Even if running Win2003 as a server doesn’t catch your fancy and in fact you would much rather get rid of your existing Window’s laptop to be replaced by a cool new Apple Mac. Unfortunately you still need the ability to run Windows-only software, why not use EC2 as your on-demand pay-as-you-go Window’s desktop replacement?  Simply configure a Windows AMI with your required software (you may have to use something like this, if software is only available on CD); you could then use Jungle Disk to easily share data (via S3) between your new shiny Mac and the AMI.  Power up and down as required, easier than using VMWare or Parallels and @ 12.5c per hour, probably cheaper too.

The post from the Right Scale folks gives a detailed overview of the new  Amazon ‘SAN storage in the cloud’ service, aka Elastic Block Store, aka EBS.  Alas, this particular cloud offering was a mirage, the post was subsequently removed (but can still be viewed on Robert Scoble’s Shared Items) it seems the post was a work-in-progress and not intended for publishing, yet!

Why was I so excited?  Amazon EC2 had two major shortcomings when it launched 2 or so years ago; the first, ephemeral IP addresses, was solved by the new Elastic IP feature; the second, ephemeral storage volumes (when you shutdown an instance the disks are wiped!) is due to be solved by EBS.  With both of these problems solved, EC2, already near perfect, would be perfect.

The article does a good job of explaining the new service…

EBS starts out really simple: you create a volume from 1GB to 1TB in size and then you mount it on a device on an instance, format it, and off you go. Later you can detach it, let it sit for a while, and then reattach it to a different instance. You can also snapshot the volume at anytime to S3, and if you want to restore your snapshot you can create a fresh volume from the snapshot.

The thing that caught my eye in the above paragraph was the snapshot facility.  Snapshots are to be stored on S3 via an EC2-specific incremental-snapshot API.  This means the volumes will come with a built-in back-up facility. This is important as EBS drives reside in one availability zone (that of the instance that they are mounted against) and do not have the data replication security offered by S3.  It also means that disk systems can be restored quickly and simply from snapshots without the overhead  (and bugs!) of writing an S3 specific incremental backup and restore utility.

Back to waiting…

UPDATE: 20th August

Wait over…

Am I worried? No, but as I become more and more dependent on such services, perhaps I will, but then again at least I’ll not be alone.  WordPress.com and countless others will be using the same excuse to their customers and unlike Renginald Perrin who had a different excuse every day for his train’s late arrival…

Ep.1   “Eleven minutes late, staff difficulties, Hampton Wick.”
Ep.1   “Eleven minutes late, signal failure at Vauxhall.”
Ep.1   “Eleven minutes late, staff shortages, Nine Elms.”
Ep.1   “Eleven minutes late, derailment of container truck, Raynes Park.”
Ep.1   “Eleven minutes late, seasonal manpower shortages, Clapham Junction.”
Ep.2   “Eleven minutes late, defective junction box, New Malden.”
Ep.4   “Eleven minutes late, overheated axle at Berrylands.”
Ep.4   “Eleven minutes late, defective axle at Wandsworth.”
Ep.5   “Eleven minutes late, somebody had stolen the lines at Surbiton.”

The previous banner was based on this photo of willow ‘down’ covering a lake-side tree at Russeltown on Blessignton Lake.

Both lakes are in fact man-made. Blessington is a reservoir for the Pollahuca hydroelectric plant and is now the major water source for most of North Kildare and large parts of Dublin City. Ballinafagh is an abandoned reservoir for the Grand Canal system and is a magical spot, particularly when visited on a summer’s evening or at dusk in winter.

I’ve also discovered s3://, a new Firefox extension for accessing Amazon S3. Really simple to use, rather than an FTP type approach, it uses the URLbar. By going to s3:// you can add your Amazon S3 credentials and then manage your buckets, upload new files, or delete existing files.

Big plus, it works with Firefox 3; S3Fox has not yet made the leap (even using Nighly Tester Tools extension to force compatibility wouldn’t work – same applies to the EC2 management extension, Elasticfox ). In fact a whole heap of extensions are not Firefox 3 RC compatible, so much so, when I rebuilt my machine this week after a disk failure, I reverted back to V2.

It’s linked to from this page on my blog (which has had 200 or so hits this month) and from this AWS Community Code page. The excessive hits on the bucket started on the 28th of Feb , the day the xlAWS code was published on Amazon and continued through most of March. Talking the size of the zip file, 133GB represents approximately 100,000 downloads. I don’t have server logging enabled on the bucket, so I can’t be sure how much is due to the other public files in the bucket (all belonging to the VBA/Proto SQLite xLite project), but as that project has been available for months and is accessible only through my website (who’s stats show a consistent 5-10 downloads per week) I’m guessing the downloads are for xlAWS.

Who would have though that there would be such interest in VBA/VB6 code for accessing AWS services! I wonder was it the Excel VBA side of the house or the dispossessed (and p*ssed off) VB6 developer hoards who downloaded it the most? Leave a comment if you downloaded and used the library, I’d love to know.

SimpleDB on the other hand is not boring, it’s an exciting new shiny thing that opens up a myriad of new possibilities; but first, I and the rest of the developer community, need to tool up and cast aside some of our cherished database design patterns (oh like, 3rd normal form, strong typing, joins, nothing major) and embrace a slightly different way of thinking, however, as much as I like a challenge, I also like to get things done.

That’s where EnterpriseDB’s new Postgres Plus Cloud Edition comes in, this is an Amazon Ec2/S3 hosted edition of their Oracle compatible PostgreSQL-based product that offers the scalability of SimpleDB but the familiarity of a traditional relational database. The “magic” is supplied by Elastra, who are also offering the same functionality against MySQL and standard PostgreSQL databases.

A Talend ETL job which I had been developing for a client, had been tested against a “normal” EnterpriseDB instance. This ETL job was part of a BI prototype trialling a Postgres Plus Cloud Edition (the new name for EnterpriseDB’s cloud offering) as the back-end database. So, I exported the job as a Java executable, fired up an EC2 instance, copied up the generated JAR files, changed the database’s hostname to that of the Postgres Plus “cloud” database, ran the ETL job and it worked. As I said, boring, nothing to report, it just worked.

Now you may be wondering what’s so special about these Elastra powered databases, surely EC2 is no different from any other Linux virtual machine, why not simply install a standard database? The problem with EC2, and it is a problem to those of us (i.e. practically every IT pro on the planet) who have come to expect highly reliable RAID backed disk storage, is the non-permanence of its disk systems.

When an EC2 instance is powered down or fails, the disk system is wiped!

That, combined with fixed (if generous) disk sizes (160GB, 850GB or 1690GB), means that often a clustered database environment is a necessity, adding considerably to the complexity. It’s this sort of complexity that SimpleDB and Elastra address.

The obvious use-case for both Elastra and SimpleDB is as data stores for OLTP applications but Elastra’s ability to handle S3-backed massive databases means the possibility of using EC2 as a data warehousing platform is also considerably strengthened. Although not obvious at first glance, SimpleDB could also act as an OLAP data store; SimpleDB massively indexed tuples as “sparse dimensions” pointing to S3 objects (SQLite databases?) that hold the fact data combined with dense/”partioning” dimensions (e.g. Time). Possible ? Yes. Fun to do? Yes. A solution that I can apply tomorrow? No, that’s why I’m glad EnterpriseDB and Elastra are delivery such a boring product!

UPDATE Ec2:

The other big EC2 missing – non-permanent IP addresses – has at last been addressed. EC2 now offers “Elastic IP Addresses”, addresses associated with an account not an instance. If the instance fails or is shut down, the IP address can either be immediately re-assigned to a new instance (no more waiting for Dynamic DNS propagation) or “reserved” for future use at a cost of USD0.01c per hour. Also, the new “multiple locations” facility puts the API changes in place to allow for location selection, hopefully a sign that we here in Europe will have “local” EC2 instances to match our European S3 buckets!

UPDATE EnterpriseDB:

It looks like IBM have invested in EnterpriseDB, possibly as a counter-weight against Sun’s acquisition of MySQL (EnterpriseDB’s targeting of Oracle’s customer base would also be an added benefit!).

It was going to be called xlS3, but while doing the exercise SimpleDB appeared on the scene, so I decided to try accessing it from Excel, particularly as both products have a lot in common; both “simple”, both “schema-less” data stores. Like the S3Helper code, the simpleDBHelper module is less of comprehensive library, more a collection of useful functions which (hopefully) make working with AWS a bit easier.

To use this code library, you’ll need to have a good grasp of the S3 and SimpleDB APIs and be reasonably proficient with VBA. This is not an end-user tool, it’s for VBA (or VB6) developers. There’s a README and some basic examples within the Excel VBA project to help you get started. Code is released “in the spirit” of LGPL, you can use it how you wish, but if you add something new to the “library” (or find/fix a bug) do let the rest of us know.

As I’ve not been able to find a pure VBA implementation of the HMAC-SHA1 hash algorithm (and I couldn’t see an implementation within the standard “Microsoft Enhanced Cryptographic Provider” ) I’ve wrapped the open source XySSL SHA1 HMAC C code in a VBA friendly DLL. This DLL (and the source, under LGPL) is included in the zip file as AWS authentication requires SHA1 HMAC signatures.

You’ll also obviously require an AWS account. Credentials are stored within the workbook’s custom properties and can be encrypted via a “key file” if required. If you intend to use this code within VB6 (or Proto) you’ll need to provide your own implementation of the AWSKeyData class in order to use a non-Excel persistence store.

You can download the project ZIP file from here.

Have fun.

UPDATE

Another alternative for calculating HMAC-SHA1 signatures in VBA/VB6 is a Google Checkout supplied COM DLL see http://code.google.com/apis/checkout/samples/Google_Checkout_Sample_Code_ASP_InstallTxt.html

Mind you, the Talend offering is very basic and I’ve not managed to get the Sratebi plugin to work, leaving Palo’s ETL Server as the front runner at the moment (drill-through capability is a winner in my book).

I’ve also been busy re-factoring my VBA SQLite and Amazon S3 code with the intention of publishing them as an Excel based micro-ETL platform. While cleaning up the Amazon AWS modules I’ve been playing with SimpleDB, I’m impressed, Excel combined with SimpleDB rocks!

I’ve also wrapped the open source XySSL SHA1 HMAC C code in a VBA friendly DLL, as searching for a VBA hmac sha1 hash implementation (essential for Amazon AWS access) has proved fruitless.

Hope to release the lot the end of next month.

UPDATE:

Thanks to Javier and Jorge from Stratebi I’ve managed to get the new Kettle Palo plugin to work. It seems that the TEST facility in the Kettle database connection dialogue throws an exception for Palo connections but the connections work fine in the actual Palo input/output steps. Did a quick test and it looks very easy to use and fits in well with the Kettle “way of doing things”.

Well, if you’re IBM you hire Damien Katz the person behind CouchDB. I think 2008 could be the year that cloud-based database services really take off…

Up until now Amazon’s S3 service offered one half of the future platform the “distributed document-centric” bit but it lacked the indexed structure part to make it a true database; but in combination with SimpleDB it’s now complete.

SimpleDB stores data in a Domain/Attribute schema-less and type-less structure having more in common with a spreadsheet than a traditional relational table. If you’ve worked with the likes of SQLite (manifest typing) or Excel (no predefined schema and manifest typing) then you’ll appreciate this is no hardship, quite the opposite in fact (I find the strong typing nature of most databases a real pain having worked recently on a SQLite combined with Excel project).

The distributed nature of SimpleDB may however pose some difficulty to those of us (i.e. almost everybody) raised in the world of ACID compliant databases. Because of the Brewer’s Conjecture effect, SimpleDB sacrifices consistency for availability and partition tolerance i.e. when you write something to the database, an immediate query may not return the updated value, subsequent queries will eventually return the new data, exactly when depends on the load and the availability of resources. Those of you already using S3 will already be living with this “feature”, and in practice you rarely notice it (most updates seem to appear immediately) but it will still pose design challenges to handle the edge cases.

The service is still in limited Beta, but the documentation is available and if you already used any other AWS product you’ll immediately feel at home. The pricing is again based on usage, the cost of storage is much higher than S3, being $1.50 per GB-month, but a GB of structured data is an awful lot of data (and the larger document style storage would be provided by S3).

If you’ve not yet tried out either S3 or EC2, now might be a good time to start, cloud computing has come down to earth, all thanks to an online book store, Amazon!