Docker MPI tutorial

This repository provides a tutorial demonstrating how to create a cluster of Docker containers on your computer and execute MPI jobs on it.

Requirements

• docker
• wget
• openssh-client (ssh-keygen executable is used)

Installation

Prepare the working copy

Execute the script: ./bootstrap

Please execute ./bootstrap --help for a description of what the script is doing.

Spawn the containers

Execute the script: ./cluster-setup N

where N is the cluster size. This script will start the containers and generate a cluster-mpirun script that can be used to execute jobd on this cluster.

Please execute ./cluster-setup --help for a description of what the script is doing.

For instance:

bash $ ./cluster-setup 4
# Starting cluster of 4 containers:
$ docker run -P -d -h node01 --name docker-mpi-01 centos7:mpi /usr/sbin/sshd -D
248774f7536a7e42059196fe526f6c33e536114abce27b6063da6e6250db0a0f
$ sleep 1
$ docker run -P -d -h node02 --name docker-mpi-02 centos7:mpi /usr/sbin/sshd -D
7a743872efcabd2dc29939191966ad3c0cb16d855af6da6e3c857b7305455c20
$ sleep 1
$ docker run -P -d -h node03 --name docker-mpi-03 centos7:mpi /usr/sbin/sshd -D
a0eae9492540f17d58273f2191356b2d8735f8e603963b5b1866cf71f7ddfb63
$ sleep 1
$ docker run -P -d -h node04 --name docker-mpi-04 centos7:mpi /usr/sbin/sshd -D
70747e640327a6349dffca85b954ac473d620296f3920113d4444e88f6f77c41
$ sleep 1
# Generating script: cluster-mpirun
# Generating script: cluster-teardown
bash $ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED              STATUS              PORTS                    NAMES
e6c71cd05052        centos7:mpi         "/usr/sbin/sshd -D"      About a minute ago   Up About a minute   0.0.0.0:32777->22/tcp    cont04
4c587d97146a        centos7:mpi         "/usr/sbin/sshd -D"      About a minute ago   Up About a minute   0.0.0.0:32776->22/tcp    cont03
3f86426eb440        centos7:mpi         "/usr/sbin/sshd -D"      About a minute ago   Up About a minute   0.0.0.0:32775->22/tcp    cont02
6efed4edd8b7        centos7:mpi         "/usr/sbin/sshd -D"      About a minute ago   Up About a minute   0.0.0.0:32774->22/tcp    cont01

Start an MPI job

Let's run one of the samples provided by IBM Platform MPI Community Edition:

bash $ ./cluster-mpirun /opt/ibm/platform_mpi/help/hello_world
$ exec docker run --rm -ti --entrypoint /usr/bin/mpirun.entrypoint --env MPIRUN_NP=4 --env MPIRUN_HOSTLIST=172.17.0.3,172.17.0.4,172.17.0.5,172.17.0.6 centos7:mpi /opt/ibm/platform_mpi/help/hello_world
Hello world! I'm 1 of 4 on 172.17.0.4
Hello world! I'm 3 of 4 on 172.17.0.6
Hello world! I'm 2 of 4 on 172.17.0.5
Hello world! I'm 0 of 4 on 172.17.0.3

Terminate the cluster

Execute the generate cluster-teardown script to get rid of Docker containers.

bash $ ./cluster-teardown
$ docker rm -f docker-mpi-01
docker-mpi-01
$ docker rm -f docker-mpi-02
docker-mpi-02
$ docker rm -f docker-mpi-03
docker-mpi-03
$ docker rm -f docker-mpi-04
docker-mpi-04

Links

• https://www.ibm.com/developerworks/community/blogs/W8932c25e7e86_409c_ab4c_b1deebf711ff/entry/developing_message_passing_application_mpi_with_docker?lang=en
• https://www.ibm.com/developerworks/community/blogs/W8932c25e7e86_409c_ab4c_b1deebf711ff/entry/ibm_platform_mpi_and_lsf_ssh_environment_setup1?lang=en

License

MIT License, see LICENSE file for more information.