Introduction
Cloud computing is growing day by day. More and more business are adopting it. Being a software engineer one has to learn the recent technologies and be relevant in the days to come. So I decided to spend some time and learn Microsoft’s azure cloud computing. In this post I am going to list down the list of road blocks and how to cross that without violating the corporate security regulations
Pay per use
Learning cloud computing involves money. A valid credit card is needed. Once a credit card is registered azure makes a test transaction of $1. Then the subscription is setup.
Azure provides a one month free trial with $150 credit. But this is too short a time to try and learn the azure offerings. Initial set of months I did pay from my own pocket and learned the azure services. The bill was not huge but it is a pain.
MSDN Subscription
As a part of our regular software upgrade I received a visual studio 2012 with MSDN subscription. MSDN subscription is a programmers treasure box. There are so many things that are available as a part of the subscription. One among them is the $50 azure credit every month. If one is careful a lot can be learned with this small credit each month. Now I don’t spend my hard earned money but use this credit. Thanks to those folks at Microsoft and our procurement 🙂
Access Azure from Powershell
Azure has 2 management portals. They provide a nice UI for every management task.
And like me if you hate UI and like the command line then there are 2 offerings from Azure
- Powershell cmdlets
- Node.js based cross platform command line tools
Being a windows user and having power shell readily available, I installed the powershell cmdlets. But because of our proxy authentication I couldn’t access the azure service from these cmdlets. After some search I found a solution. Including the following line in powershell profile, makes powershell talk to the azure REST api through our proxy.
[System.Net.WebRequest]::DefaultWebProxy.Credentials = [System.Net.CredentialCache]::DefaultCredentials
Programming for Azure
Azure SDK provides 2 emulators. So before deploying the program to Azure one can locally build and test with these emulators.
- Azure compute emulator
- Azure storage emulator
And at times when I had to access the azure service from a local program through our proxy authentication then the following trick similar to the powershell one works. Add the following block to the app.config
<system.net>
<defaultProxy useDefaultCredentials="true" />
</system.net>
SSH is blocked
To feel the power of windows azure finally I reached the point when I had to create and use the virtual machines. Here again our proxy blocks both RDP & SSH for the security reasons. Without these protocols I cannot do anything with the virtual machines. I thought of solving this problem using the cloud itself and found a nice solution. After some searching around I found the awesome “shell in a box” from google code. This exposes a shell through a web interface. It also supports https. Now this is how I have made my setup.
- I have one small VM (Basic/A0) with shell in a box running at 443 (It is speaking https for security reason). This has to be setup onetime from outside office.
- I start this machine using powershell and ssh into it using a browser.
- From that VM I ssh into any other machine if needed. (yes the whole world is just a ssh away)
- Once I am done I shut down this machine using powershell.
Keep an eye on the $$$
Last and important point is the money that is involved in learning cloud computing. Always do the following without fail or else all the free credit will be burnt soon and one has to wait for a month to continue the exciting journey.
- Always keep a tab on the azure credit.
- Based on the utilization it will be green or red.
- Green means no need to worry. But in case if its red then the money in the subscription will not last for the entire month.
- Always shutdown the VM/service instances that are not needed immediately (not at the end of the day).
- If there is a need to preserve the IP keep the cloud service running and shutdown only the VM.
- For some services like websites, database etc there is a free tier available. Use them instead of the paid tier.
- Some services like redis cache are way too costly. Be careful with them.
- And my rule of thumb is compute is always costlier than the storage.
I am still exploring the technologies. I hope this helps someone who wants to learn cloud computing…
–Ferose
Ferose Blog 