Cluster customisation: AWS¶
An Alces Flight Compute environment contains many useful tool and utilities designed to assist users in running a diverse range of jobs and workflows. Also included are tools to help users customise their cluster environment further, allowing automated setup of a range of features including:
- Distribution package installation
- External storage mounts
- Custom script execution at launch time
The Alces customiser tool requires some setup tasks in order to appropriately work with your AWS account and deployed Alces Flight Compute environments. Follow the steps below to enable the customiser for your AWS account.
To begin setting up the Alces customiser tool - log in to your Alces Flight Compute environment as the administrator user. From there, run the
alces about node command - this will display information about your environment; e.g.
[alces@login1(scooby) ~]$ alces about node Clusterware release: 2016.4.1 Customizer bucket prefix: s3://alces-flight-a1i0ytdmvzv3ztv3/customizer/default Platform host name: ec2-52-51-77-141.eu-west-1.compute.amazonaws.com Public IP address: 188.8.131.52 Account hash: a1i0ytdmvzv3ztv3
A new S3 bucket must be created using the prefix provided in the information above. Using one of the available tools, such as
s3cmd or the S3 web console - create a new bucket with an appropriate name; for instance, in the example above the bucket would be called:
Once the bucket is created - create a “folder” within the bucket named:
Now, from within the
customizer folder - create another folder named
default, this sets up the
default customiser profile.
From within the
default folder, we must create a folder where all customisation scripts should be placed. Create a new folder within the
default folder named:
It is important that the bucket and folders are created with the correct names - failing to create the bucket and folders with the correct names will mean that the Alces customiser will not be able to locate customisation information.
Your AWS account is now ready for use with the Alces customiser tool.
Using custom S3 buckets¶
You may also wish to use a custom S3 bucket rather than the automatically generated Flight bucket name. To do so, simply follow the above steps to create a bucket in the same location, changing
default for a different identifier. For example, the following location could be created to hold customisation scripts for a specific environment:
To use custom S3 buckets with Alces Flight Compute, enter your S3 bucket URL in the
FlightCustomBuckets CloudFormation parameter, without the S3 prefix. For example, to launch a cluster using customisation scripts from the bucket in the above example, a user could specify the following value at launch time:
Setting up customisation scripts¶
Customisation scripts are run on each node in your environment upon joining the cluster network - example customisation scripts include distribution package installations and external storage mounts. The Alces customiser supports any Linux executable file type.
The following simple example customisation shell script would install the
emacs editor on each node within your environment:
#!/bin/bash yum -y install emacs
Customisation scripts are run in unattended mode, and should be written to complete with interactive input.
Once the bash script has been created - upload it to your S3 bucket into the
configure.d folder previously created, for example:
You can upload multiple customisation scripts to the
default folder - each of the scripts will be run.
The output of each customiser script run is sent to the file
/var/log/clusterware/instance.log on each of the nodes. Each subsequently deployed Alces Flight Compute environment will run each of the customise scripts included in the
Using alternate customisation profiles¶
Alternate customisation profiles can be set up and used with the Alces customiser tool. To set up another profile, from your S3 bucket in the
customizer folder - create another profile folder, for example
foo folder - create the
configure.d folder. Place any customisation scripts for the
foo profile within the
To use custom profiles when launching the Alces Flight Compute CloudFormation templates, enter the profile name(s) in the
FlightCustomProfiles parameter - the customiser tool will then run each of the scripts in the