.. _aws: =========================================== Amazon Web Services EC2 AMI [2014 version] =========================================== We are using a wide variety of software in this class, much of which is probably not found on your computer. It is all open source software (see :ref:`licences`) and links/instructions can be found in the section :ref:`software_installation`. You can also use the :ref:`vm`. Another alternative is to write and run your programs "in the cloud" using Amazon Web Services (AWS) Elastic Cloud Computing (EC2). You can start up an "instance" (your own private computer, or so it appears) that is configured using an Amazon Machine Image (AMI) that has been configured with the Linux operating system and containing all the software needed for this class. You must first sign up for an account on the `AWS main page `_. For this you will need a credit card, but note that with an account you can get 750 hours per month of free "micro instance" usage in the `free usage tier `_. A micro instance is a single processor (that you will probably be sharing with others) so it's not suitable for trying out parallel computing, but should be just fine for much of the programming work in this class. You can start up more powerful instances with 2 or more processors for a cost starting at less than 3 cents per hour (the m3.large on-demand instance). See the `pricing guide `_. For general information and guides to getting started: * `Getting started with EC2 `_, with tutorial to lead you through an example. * `EC2 FAQ `_. * `Pricing `_. Note: you are charged per hour for hours (or fraction thereof) that your instance is in `running` mode, regardless of whether the CPU is being used. * `High Performance Computing on AWS `_ with instructions on starting a cluster instance. * `UW eScience information on AWS `_. Launching an instance with the *uwhpsc* AMI ------------------------------------------- Quick way ^^^^^^^^^ Navigate your browser to ``_ You should then be on a page where you see you are on Step 2 of 7 at the top of the page, "Choose instance type". Then you can skip the next section and proceed to :ref:`aws_instance_type`. Search for AMI ^^^^^^^^^^^^^^ **Skip this section** if you followed the "quick way" instructions above. Going through this part may be useful if you want to see how to search for other AMI's in the future. Once you have an AWS account, sign in to the `management console `_ and click on the EC2 tab, and then select Region US West (Oregon) from the menu at the top right of the page, next to your user name. You should now be on the page ``_. Click on the big "Launch Instance" button. On the next page, you will see a list of "Quick start" Amazon Machine Images (AMIs) that you can select from if you want to start with a fresh VM. For this class you don't want any of these. Instead click on the "Community AMIs" tab and then type `uwhpsc2014` in the search bar. Select this image. You will then be taken to Step 2, "Choose instance type". .. _aws_instance_type: Choose instance type ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ On the next page you can select what sort of instance you wish to start (larger instances cost more per hour). t1-micro is the the size you can run free (as long as you only have one running). Click `Continue` on the next few screens through the "instance details" and eventually you get to one that asks for a key pair. If you don't already have one, create a new one and select it here. You can now skip over steps 3-6 and jump directly to Step 7, "Review and Launch". Launch instance / create key pair ----------------------------------- When you click on "Launch", you will get a page that asks you to "Select and existing key pair or create a new one". If you don't already have a key pair, select "Create a new pair" from the menu and follow instructions. If you give the name `mykey`, for example, then this will download a file `mykey.pem`. Store this file in a directory where you can find it again, since you will need this key in order to log in to your instance once it is running. You also need to change the permissions on this file so that is readable only by the account user. In the directory where this file lives, give the command:: chmod 400 mykey.pem If the file is more widely readable then you will not be able to use this key to log into your instance. Logging on to your instance --------------------------- Click `View Instances` on the page that appears to go back to the Management Console. Click on `Instances` on the left menu and you should see a list of instance you have created, in your case only one. If the status is not yet `running` then wait until it is (click on the `Refresh` button if necessary). *Click on the instance* and information about it should appear at the bottom of the screen. Scroll down until you find the `Public DNS` information Go into the directory where your key pair is stored, in a file with a name like `mykey.pem` and you should be able to `ssh` into your instance using the name of the public DNS, with format like:: $ ssh -Y -i KEYPAIR-FILE ubuntu@DNS where KEYPAIR-FILE and DNS must be replaced by the appropriate things, e.g. something like this:: $ ssh -Y -i mykey.pem ubuntu@ec2-50-19-75-229.compute-1.amazonaws.com Note: * You must include `-i keypair-file` * You must log in as user ubuntu. * Including -Y in the ssh command allows X window forwarding, so that if you give a command that opens a new window (e.g. plotting in Python) it will appear on your local screen. * See the section :ref:`ssh` for tips if you are using a Mac or Windows machine. If you use Windows, see also the Amazon notes on using *putty* found at ``_. Once you have logged into your instance, you are on Ubuntu Linux that has software needed for this class pre-installed. See the file `install.sh` in the running instance to see the commands that were used to install software. Other software is easily installed using `apt-get install`, as described in :ref:`software_installation`. Transferring files to/from your instance ---------------------------------------- You can use `scp` to transfer files between a running instance and the computer on which the ssh key is stored. From your computer (not from the instance):: $ scp -i KEYPAIR-FILE FILE-TO-SEND ubuntu@DNS:REMOTE-DIRECTORY where DNS is the public DNS of the instance and `REMOTE-DIRECTORY` is the path (relative to home directory) where you want the file to end up. You can leave off `:REMOTE-DIRECTORY` if you want it to end up in your home directory. Going the other way, you can download a file from your instance to your own computer via:: $ scp -i KEYPAIR-FILE ubuntu@DNS:FILE-TO-GET . to retrieve the file named `FILE-TO-GET` (which might include a path relative to the home directory) into the current directory. Stopping your instance ---------------------- Once you are done computing for the day, you will probably want to stop your instance so you won't be charged while it's sitting idle. You can do this by selecting the instance from the Management Console / Instances, and then select `Stop` from the `Instance Actions` menu. You can restart it later and it will be in the same state you left it in. But note that it will probably have a new Public DNS! Creating your own AMI --------------------- If you add additional software and want to save a disk image of your improved virtual machine (e.g. in order to launch additional images in the future to run multiple jobs at once), simply click on `Create Image (EBS AMI)` from the `Instance Actions` menu. Viewing webpages directly from your instance -------------------------------------------- An apache webserver should already be running in your instance, but to allow people (including yourself) to view webpages you will need to adjust the security settings. Go back to the Management Console and click on `Security Groups` on the left menu. Select `launch-wizard-1` and then click on `Inbound`. Click on `+Add rule`. You should see a list of ports that only lists 22 (SSH). You want to add port 80 (HTTP). Select HTTP from the drop-down menu that says `Custom TCP Rule` and then click on `+Add rule` and `Apply Rule Change`. Now you should be able to point your browser to `http://DNS` where `DNS` is replaced by the Public DNS name of your instance, the same as used for the `ssh` command. So for the example above, this would be :: http://ec2-50-19-75-229.compute-1.amazonaws.com The page being displayed can be found in `/var/www/index.html` on your instance. Any files you want to be visible on the web should be in `/var/www`, or it is sufficient to have a link from this directory to where they are located (created with the `ln -s` command in linux). So, for example, you could do the following (this has already been done if you start with the uwhpsc2104 AMI):: $ cd $HOME $ mkdir public # create a directory for posting things $ chmod 755 public # make it readable by others $ sudo ln -s $HOME/public /var/www/public then you can see the contents of your $HOME/public directory at:: http://ec2-50-19-75-229.compute-1.amazonaws.com/public Remember to change the DNS above to the right thing for your own instance!