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 customizer command - this will display information about your environment; e.g.
[alces@login1(scooby) ~]$ alces about customizer Customizer bucket prefix: s3://alces-flight-a1i0ytdmvzv3ztv3/customizer
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, you must create a folder for each customisation event you would like to add customisation scripts for; customisation scripts for this event will then be placed in this folder. See Customisation Events for the different events available.
If you are unsure which event you should use, for most simple customisations such as installing additional system packages or creating new users you will probably want the
configure event. In this case you would 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.
Setting up Customisation Scripts¶
Customisation scripts are run on each node in your environment when the particular customisation event occurs - 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 without 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 each event folder within the profile folder - each of the scripts will be run whenever the given event occurs.
The output of each customiser script run is sent to the file
/var/log/clusterware/instance.log on each of the nodes; each output line will be prefixed with
[cluster-customizer:<event>], identifying the event which produced it.
Customisation Script Environment¶
Customisation scripts are run in the standard environment for whichever interpreter they are specified to be executed with, without loading any additional configuration. In particular this means that, in the case of customisation scripts intended to be run using Bash, configuration files for login shells are not loaded.
One consequence of this is that the
alces command, which is defined as a shell function for cluster node login shells, is not available by default within customisation scripts. However, you can still run
alces commands within your customisation scripts in either of the following ways:
- Run the
alcesbinary directly, which can be done like this:
/opt/clusterware/bin/alces gridware depot install benchmark
- Alternatively you can make the
alcescommand available on your
PATH, which you may prefer if you want to run several
alcescommands. This can be done like this:
PATH="/opt/clusterware/bin/:$PATH" alces gridware depot install benchmark
Applying Customization Profiles¶
There are 3 ways in which a feature profile can be applied to a system. Each method applies the profile in a slightly different way.
To apply profiles when launching the Alces Flight Compute CloudFormation templates, enter the profile name(s) in the
Customization profiles to enable parameter - the customiser tool will then run each of the scripts in the
foo profile. This will apply the profile to all systems (both the login & compute nodes) when they boot up.
If the profile(s) you wish to use are in a different storage container than the default, see Using Custom S3 Buckets.
In order to use multiple profiles, separate them with a space in the
Customization profiles to enable parameter. (e.g.
Using Customize Apply¶
The profile can be applied to live systems with
alces customize apply account/foo which will execute the profile on the current machine.
To apply the profile to all nodes run:
module load services/pdsh && pdsh -g nodes "alces customize apply account/foo"
This profile will not be added to any default location so any nodes brought up with autoscaling will not have the profile applied
Using Customize Slave Apply¶
To set a profile to be run on all compute nodes when brought up (with autoscaling), add the profile to the slave list from the login node with:
alces customize slave add account/foo
The profile can then be seen by running the list command from the headnode:
[alces@login1(scooby) ~]$ alces customize slave list account/foo
This profile can be removed from the slave list with:
alces customize slave remove account/foo
This will not apply the profile to any currently running compute nodes. To apply it to any running nodes see Using Customize Apply
Script Events & Parameters¶
A number of different customisation hooks are available to Flight Compute nodes when different events occur:
initialize: occurs at boot;
configure: occurs once the cluster configuration file
/opt/clusterware/etc/config.ymlfile is detected (this is usually immediately available unless you are manually launching a cluster without using an Alces Flight CloudFormation template);
start: occurs once configure phase has completed (this event often starts services);
node-started: occurs once start complete (the node is ready);
fail: occurs should the cluster configuration file not be detected after 300 seconds;
member-join: occurs when a new node has joined the cluster (note: this event will also occur on the joining node itself);
member-leave: occurs when a node has left the cluster.
Customisation scripts can be added for each of these events by placing scripts within an appropriately named folder for the event (e.g.
configure.d, for scripts to run on the
configure event), within a profile folder (e.g.
default, or see Alternate Customisation Profiles), within the
customizer folder of your S3 customisation bucket. See Setup tasks for full details of setting up customisation scripts.
Customisation Script Parameters¶
Customisation scripts for each of the customisation events receive particular additional parameters, providing more information on the event and node, so that you can modify your script’s behaviour based on these. These are as follows:
If the node has not yet been configured (i.e. it is a clean boot, not a reboot), then the only parameter received is a literal
once. Otherwise no parameters are supplied.
- 1: The name of the event being run (allowing a single script to be reused for multiple events), e.g.
- 2: The role of the instance, i.e.
master(login/head node) or
- 3: The name of the cluster (allowing a single script to behave differently for particularly named clusters).
As above, plus:
- 4: Path to a file that contains information about the member.
- 5: Hostname of the member.
- 6: IP address of the member.
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 steps at Storage Configuration to create a bucket in the same location, changing the bucket name 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
S3 bucket for customization profiles 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:
S3 bucket for customization profiles: alces-flight-a1i0ytdmvzv3ztv3
Alternate Customisation Profiles¶
Creating Alternate Profile¶
Below are 2 different methods for setting up a custom profile. The first details the steps taken to setup a custom profile from within a live stack and pushing it to the storage repository, the second details creating the profile before bringing up a Flight stack.
From Live System¶
There are few bits of trickery needed to configure a new profile from the command line. It’s recommended to do this from the login node and push to the storage repository upon completion.
Create a temporary file named after the desired profile name (
foois used for this example):
Create profile in the accounts repository (this will generate the
foo/configure.d/foo.shfilesystem structure within the default customizer location [s3://alces-flight-<account hash>/customizer/]):
alces customize push foo.sh account
Download foo repository:
alces customize apply account/foo
Add new scripts & make changes to the profile in
s3://alces-flight-<account hash>/customizer/foo/through AWS (for more info on different stages see Customisation Events)
Download new scripts from the repo and run them:
alces customize apply account/foo
Alternate customisation profiles can be set up from the S3 customizer bucket (e.g.
s3://alces-flight-a1i0ytdmvzv3ztv3/customizer/). To set up another profile, from your S3 bucket in the
customizer folder - create another profile folder, for example
Create folders for the customisation events you want to handle (e.g. create a
configure.dfolder. Place any
configurecustomisation scripts for the
fooprofile within the
Create a file called
foodirectory) which lists all of your customisation scripts as below:
start.d/script.sh configure.d/emacs.sh configure.d/test.sh
Feature profiles are available to add further functionality to a Flight environment. These features can be schedulers, applications or environment tweaks. One of the main benefits of feature profiles is that it allows for the automatic installation of commercial software that cannot be distributed with Alces Flight & gridware. Feature profiles also allow for the automation of complex installations which are out of the scope of gridware.
To show available features profiles:
[alces@login1(scooby) ~]$ alces customize avail feature/ansys-fluent-v170 software feature/configure-beegfs software feature/configure-docker software feature/configure-ephemeral-disks config feature/configure-users config feature/disable-hyperthreading config feature/ellexusmistral software feature/enginframe-2015.1 software feature/enginframe-2017.0 software
The above output has been shortened to save space on the documentation, there are many more features available on a running Flight instance
Installing a Feature Profile¶
Installing a new feature profile is done in much the same way as applying an alternate customisation profile.
Apply customisation feature:
alces customize apply feature/ansys-fluent-v170
If any of the files for the installation are missing then an error message similar to the following will be displayed:
Running event hooks for ansys-fluent-v170 Running configure hook: /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170/configure.d/install.sh download: 's3://alces-flight-<account hash>/apps/ansys-fluent/FLUIDS_170_LINX64.tar' -> '/tmp/FLUIDS_170_LINX64.tar' [1 of 1] download: 's3://alces-flight-<account hash>/apps/ansys-fluent/FLUIDS_170_LINX64.tar' -> '/tmp/FLUIDS_170_LINX64.tar' [1 of 1] ERROR: S3 error: 404 (Not Found) download: 's3://alces-flight-<account hash>/apps/ansys-fluent/fluent-license.lic' -> '/tmp/fluent-license.lic' [1 of 1] download: 's3://alces-flight-<account hash>/apps/ansys-fluent/fluent-license.lic' -> '/tmp/fluent-license.lic' [1 of 1] ERROR: S3 error: 404 (Not Found) ****************************************************************************** Please download the Fluent installation file(s) from the download link provided by Ansys. If you do not have a download link, please contact Ansys support at firstname.lastname@example.org. Copy the installation archive and license file to /tmp on this machine: /tmp/FLUIDS_170_LINX64.tar /tmp/fluent-license.lic For repeatable installation, upload to your Alces Flight S3 customization bucket: s3://alces-flight-<account hash>/apps/ansys-fluent/FLUIDS_170_LINX64.tar s3://alces-flight-<account hash>/apps/ansys-fluent/fluent-license.lic Once you have placed the files in one of these locations, run the following command: alces customize trigger configure feature-ansys-fluent Installation will then continue. ****************************************************************************** No start hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170 No node-started hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170 No member-join hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170 No member-join hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170
To make the installation files available for any Flight instances on the same AWS account - save them to
s3://alces-flight-<account hash>/apps/app-name/ instead of
alces-flight-<account-hash> is the name of the bucket in
alces about customizer and
app-name is the name of the app feature minus the version number (in the example above,
ansys-fluent-v170 would become
ansys-fluent). The names of the files should match those mentioned in the error output.
Once the required files are in place the installation will run through (this example shows the feature profile being applied after the files have been added to S3):
Running event hooks for ansys-fluent-v170 Running configure hook: /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170/configure.d/install.sh download: 's3://alces-flight-<account-hash>/apps/ansys-fluent/FLUIDS_170_LINX64.tar' -> '/tmp/FLUIDS_170_LINX64.tar' [1 of 1] download: 's3://alces-flight-<account-hash>/apps/ansys-fluent/FLUIDS_170_LINX64.tar' -> '/tmp/FLUIDS_170_LINX64.tar' [1 of 1] 7125760000 of 7125760000 100% in 82s 82.21 MB/s done download: 's3://alces-flight-<account-hash>/apps/ansys-fluent/fluent-license.lic' -> '/tmp/fluent-license.lic' [1 of 1] download: 's3://alces-flight-<account-hash>/apps/ansys-fluent/fluent-license.lic' -> '/tmp/fluent-license.lic' [1 of 1] 26 of 26 100% in 0s 925.40 B/s done Unpacking tarball FLUIDS_170_LINX64.tar ... Starting Ansys Fluent installer... cp: cannot stat ‘/tmp/fluent-license.lic’: No such file or directory Installing and Configuring modulefiles... Ansys Fluent installation completed. No start hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170 No node-started hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170 No member-join hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170 No member-join hooks found in /opt/clusterware/var/lib/customizer/feature-ansys-fluent-v170
If the required files have only been uploaded to S3 then the installation will take a little longer while it copies the data locally to the login node