Visual depiction of the rotating Moodle architecture

I have a plan to back up Wheaton’s Learning Management System (LMS) to the cloud on a yearly basis. I talked about the basics of this architecture in my post I <3 Redmine and You Will Too.Essentially each academic year I will rotate a years worth of Moodle into the cloud, only keeping the current year and the previous year.  Here’s a picture to give you a little help in understanding.

So now I need to find a way for people that are not me to access the Moodle that lives in the cloud.  The problem is that every moodle has a config file, and in that config file, Moodle asks you to specify the URL for where your Moodle is located, this is slightly problematic because:

1. Amazon EC2 servers are not given IP addresses, they are given a Public DNS like
2. Technically they can be assigned to an IP address but Elastic IPs cost money when they aren’t being used, and frankly I would rather not have to pay extra if I don’t have to.
3. The people accessing these Moodles can’t be expected to ssh into a server and change the config file.

So I need to make this happen automagically when the server starts up.  I tried using the php variable $_SERVER but I got some weird things.  So my idea is to have a start up script call the public-hostname (using the API amazon provides) and then edit the config file.  That way when the server starts up, Moodle will automagically be available.

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I never argued *against* PHP/Python/Perl or even use of Linux/Apache by PaaS vendor. Just noted PaaS users *shouldn’t* care.

I apologized and asked for clarification since it seemed to me that there was an argument about whether or not a PHP/Perl cloud was necessary.

I re-read the article a few times, and on the last go around the only new explanations I could see from it was:

1. if i wrote in php a vendor would deploy in another language
2. he meant that the LAM in LAMP was what didn’t matter  (although that didn’t seem to be explicitly stated)

In the meantime though, I’ll just wait for a response (I sent it late last night and people tend to sleep) rather than possibly misinterpret more.

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James’ last question: “Is the ‘open sourceness’ of a programming stack even that important anymore?” is a good one, but orthogonal to the discussion about a LAMP/PHP cloud, in my mind.

So why has this conversation gotten me in a tizzy and forced me to write two blog posts in one week?  Well two reasons:

1. Many web based open source projects are built on the back of P languages (PHP, Perl, and Python)
2. The cloud exists to make technology easier for the masses.

Now before I go any further I will disclose that the first language I learned was PHP.  The second one was Perl.  While I know there are wars that start on listservs about what languages are better, that is not the purpose of this post, so put it out of your head and don’t say anything about how much you think PHP sucks in the comments.

Web based open source projects are built on the back of P languages

Now I could write something about this, but I like lists.  So here is a brief off the cuff list of what open source projects use P languages:

1. MediaWiki (PHP)
2. WordPress (PHP)
3. Bugzilla (Perl)
4. Drupal (PHP)
5. Plone (Python)
6. Moodle (PHP)
7. AWStats (Perl)
8. MovableType (PHP and Perl)
9. Subversion (Python and C)
10. Trac (Python)

Now, I’m not going to argue the merits of how good each of these piece of software are. Again that’s not my point.  But they are popular whether you like it or not.  And to just dismiss them would be foolish.

The cloud exists to make technology easier for the masses

Google Docs makes it easier to get to files you need to edit.  Heroku makes it easier to deploy Ruby on Rails apps.  Amazon EC2 makes it easier for you to deploy a server.  The fall out of the cloud is that technology suddenly becomes much easier to create and deploy.

So what happens when my mom wants to write her own blog.  Well, most likely she heads over to WordPress.com and creates a blog for herself.  And if she needs a little more, then she signs up for the WordPress Premium services.  But what if I want my own blog.  Well right now I have my friend hosting my stuff.  But what if I want it hosted elsewhere and I don’t want to maintain servers (since I do that all day long).  My only option right now is to do what my mom is doing, but the reality is, that’s not what I want.  I want something like Heroku but for PHP.  And if I had it, I could install any of the PHP applications listed above.

And I think this conversation is very pertinent given that Google just announced its open source learning management system written in Python and intended to be deployed in Google App Engine.  This could potentially be a big blow to Moodle who doesn’t have a cloud to turn to.

Conclusion

So yes a PHP based cloud does matter.  And yes it should be built because there are lots of people clamoring to use it (or who have already figured out a way).

And yes this blog post could be more coherent.

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Visual depiction of the rotating Moodle architecture

I’m in the process of setting up an architecture for Moodle. Essentially using VMWare I’ll rotate out servers every academic year.  Older server images will be put in the cloud so that if we need access to them quickly, we can do that without any problems.  This will allow me to:

1) get away with not having to do necessary MySQL tuning since Moodle doesn’t really delete much from its database.

2) not have to deal with compatibility issues since Moodle has been know to create course back ups that don’t work with future versions of the software.

3) deal with file storage issues, namely that users often thing the course management software is the place to store all of your files for ever and ever (its not by the way).

So now that I’ve come up with that I need a way to figure out what I have to do to make this work and then hope that I don’t forget those tasks.  Enter Redmine.  If you haven’t used it before, I recommend checking it out.  There is a demo redmine you can use to play around with it.

tasks that need to be accomplished in order to set up the Moodle architecture.

What I like about it is its flexibility.  At MPOW I am essentially a developer, systems administrator, and project manager all rolled up into one.  Its a lot of hats to wear, and often times I forget tasks, or I need to talk out the entire process.  Essentially I use Redmine to help me with that.  I can enter new features for the developer Rosalyn to work on.  I can enter tasks for sys admin Rosalyn to work on.  And all of this is done by project manager Rosalyn who is trying to help the sys admin and developer work together (yes i do talk to myself…and answer back).

Redmine has subtasking, subprojects, and you can change all kinds of things in it so that it can essentially function however you want it to.  And its written in Ruby on Rails so extending is easy (although the plugins are plentiful so you may not even need to write your own code).  I’ve gotten my boss on board with it, and he’s slowly trying to infect others so that they use it too.

So that’s my new best friend Redmine.  It has helped me organize and focus my day on the things that need to get done.  I <3 it and if you try it out, I think you will too.

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I was asked to write a piece on the cloud (I know you’re shocked) in the upcoming issue of Educause Quarterly which will be dedicated to the cloud. If you’re peer reviewing for that particular journal, we will now pause so that you can close the window (the peer review process is double blind) ………………………………………………………………………………………..

Ok good. Now that they’re gone. Here is a link to a first pass at my article:

Defining Cloud Computing

Essentially its a rehash of my presentation at NERCOMP with a bit more depth and significantly fewer audience members asking questions (not that I mind questions…that was my favorite part by far. its just that i didn’t actually get to finish the presentation properly because there were so many questions). The article itself defines the cloud, and then uses videos to illustrate each of the definition’s points.

Questions, comments, and feedback are welcome.

And yes, I was trying to be funny when I used the cloud to deliver an article on the cloud (see web address of article for more details).

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As a companion to this presentation. I’m doing a survey, to see what kind of things institutions are using in the cloud. Its definitely not a comprehensive list of what’s in the cloud or even what’s possible in the cloud, but my presentation is only 40 minutes.

At any rate, if you work in academia and you’re interested in/using cloud computing, please please please take my survey.

http://www.surveymonkey.com/s/cloud-academia

Your help will be greatly appreciated.

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First I always recommend keeping up the old installation while you’re migrating and not taking it down for at least a week or two (perhaps even longer if you’re paranoid).  That way if you need to, you can always go back.

Here are the steps that I followed:

1. I installed a blank MDID2 to make sure that I had everything I needed on the server to make MDID2 work.  When installing MySQL I made sure that it was the same version as the old server to ensure that MySQL weirdness didn’t interfere with the installation.  For instructions on installing MDID2, I used the MDID wiki’s instructions.  I actually ran the system and had our Visual Resources Curator test things out to see if it worked like he expected a fresh MDID would work (because lets face it, I don’t know nearly as much about the system as he does).
2. Once our Visual Resources Curator gave me the thumbs up I mounted, as a network drive, the directory on the old server that had the MDID2 files and images.  I then copied ALL of the files over to the new directory on the new server.  I then went home for the night…because that’s going to take a while.
3. The next morning go into the config.xml file (found at the root level of mdid2) and change the information in the file so that it’s settings match your new servers configuration.  Most likely all you’ll need to do is change the location of the image files or the username and password of the database, but you should check over the rest of the file just to be safe.
4. Create a mysqldump of the old database using: mysqldump -u mdid2 -p -q mdid2 > mdid2export.sql I then moved the dump over to the new server.  Keep in mind that your MySQL command may be different if:
   • you don’t use passwords
   • have a different MySQL user set to run mdid2
   • your mdid2 user doesn’t have privileges to do this type of command.
5. Once I got the dump onto the new server I opened the dump file in notepad and did a find replace.  In my case on the old server mdid was on the d drive and on the new server it was going to be on the c drive.  So I had notepad go through the file and find all instances of d:\\mdid2\\ and replace it with c:\\mdid2\\.  Again this may be different for you, depending on how your installation is set up.  Once this started I went to go get myself some tea, because this was going to take a bit (although not as long as moving all those files over).
6. Now that the database file has been “fixed” you’re ready to import the database.
   1. Go into MySQL’s commandline and drop the existing mdid2 database: drop database mdid2;
   2. Recreate the mdid2 database: create database mdid2; The reason you just destroyed and recreated the database was because the database has structure and data attached to it based on the work you did in step 1, you want to overwrite that.
   3. import the mysql database by going to Window’s commandline and doing: mysql -u mdid2 -p mdid2 < mdid2export.sql
7. This step is key to avoiding any indexing weirdness you may see.  Trust me, I did these steps multiple times before finally figuring this out (thanks to the mdid listserv).  You’ll need to go in and delete all instances of the _ftindex directory in the image directory.  Go through each and every directory in the mdid2/image directory to get rid of this folder.  If you don’t you’ll find some weirdness in the indexing of data.  Don’t worry this directory will be rebuilt once you start up mdid2.
8. Start up IIS and wait a bit for the full text index to finish up.  If you want, you can log in to your newly migrated MDID2 and click background transactions to see if the indexing process is still running (it should be the second thing in the list).
9. Last but certainly not least, have your Visual Resources Curator check the system over and give their stamp of approval.  Without that, you might as well be dead in the water.

Like I stated above, this is the process that I followed.  Everyone’s systems are set up differently, but hopefully this can act as a guide of sorts to whatever poor schmuck needs to do something similar (ie me…so I don’t forget like I always seem to).

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The first thing I did was start with an already existing EBS AMI. Right now there aren’t too many available but they are growing.  I chose an Ubuntu 9.04 image since I’m going to install a stack on it, and I’ve already done *most* of it before on Ubuntu.

A quick note: it is possible to create an EBS AMI from an S3 AMI, but I wasn’t able to figure that out (quickly).  Although I did find a script that will do this for you: http://gist.github.com/249915.

Next, I wanted to get the Ubuntu server prepared.  I needed to:

• install mysql — http://www.howtogeek.com/howto/ubuntu/install-mysql-server-5-on-ubuntu/
• install ruby on rails — http://www.hackido.com/2009/04/install-ruby-rails-on-ubuntu-904-jaunty.html (up to and including step 6)
• install zlib — http://www.techsww.com/tutorials/libraries/zlib/installation/installing_zlib_on_ubuntu_linux.php
• install blacklight — http://projectblacklight.org (includes solr and a number of gem dependencies)

I did all of this.  One thing I noticed, Blacklight requires me to use non-standard ports (ie not 22 and 80).  While the server was running, I went into the AWS console and opened ports for its associated security group.  The changes took effect immediately.  I definitely liked that.

Finally, I went in to the AWS Management Console and chose “Create Image (EBS AMI)”.

Then I filled in the information including a description of my image:

and voila! EBS backed AMI.  the one caveat is:

DON’T TERMINATE THE INSTANCE UNTIL THE NEW AMI HAS FINISHED BEING CREATED

because then you’ll loose all the work that you have just done.  doh!

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So I’m still here thinking. I’ll probably be posting on cloud computing a bit more, since I will be presenting with Michael Klein from Oregon State University, on the topic.  So look forward to that (or don’t…).

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and if you don’t have a google wave account, here is what it looks like.  What’s nice about it is that you can customize the look with different background and font colors.  Also pretty cool, I can edit the wave from within my blog post.  I have to be logged into my wave account (either in another browser window or the same browser window if i’m using tabs).

I can definitely see the usefulness of this.  I’ve seen some conferences try to figure out ways to aggregate information.  By adding the twitter bot and other bots, I may be able to use wave as a quick and easy way to aggregate information.

A few bummers:

1. default colors are less than ideal, but luckily you can change that. so for example right now my code to embed the wave reads: wave id =”your-wave-id” bgcolor=”#FAEBD7″ (enclosed within brackets)
2. people that don’t have a wave account can’t see the wave.  here is what they see: this is kind of a big let down.  it would be useful if they could at least view the wave…but unfortunately that’s not the case.

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