These are the instructions for automatically configuring and deploying
EHOS on a virtual machine (VM) in an OpenStack environment in three
easy steps as outlined here: 
- Installation of ehos
- configures the openstack firewall, uploads ssh keys and creates the necessary VM images
- deployment of the ehos daemon on a newly created VM
The full installation documents can be found here here and covers in greater detail the inner workings of, and how to deploy, ehos in various environments.
The deployment computer needs to have python 3.4 (or later) and virtualenv installed to be able to use the EHOS setup & deployment scripts
There are two types of configuration files, one is to control the behaviour of the ehos deployment script and daemon and the others for installing and configuring the compute nodes. The files can be found in share/. Upon alteration it is recommended to place the altered file in etc/ to distinguish them from the original template ones. Unless you want to install additional software on the execution nodes you should only need to alter the ehos.yaml file.
There is an example etc/ehos.yaml.example file provided. This will needed to be renamed to etc/ehos.yaml and credentials for openstack connection filled in, eg: username, password, vm-image etc. The remainder of the file regards the behaviour of the ehos daemon, like the max number of nodes to create etc, and htcondor specific customisation. The template-file, with its comments, should be self explanatory. In the HTCondor section it is important to change the password to something unique as this restricts what nodes are allowed to connect to the EHOS instance.
The configuration files for VM creation are all cloud-init files in yaml format. These configuration files can either be used as is or as templates for tweaking the system. Notice that all the files have been created for centos 7 systems, so alterations might be required if your system differs from this.
# create a python 3.X virtual environment, download EHOS and install the EHOS requirements.
virtualenv -p python3 ehos
#create and activate your ehos python virtualenv
cd ehos
# for bash
source bin/activate
# for (t)csh
source bin/activate.csh
# install ehos v1.0.0-rc2 along with various requirements:
pip install git+https://github.com/elixir-no-nels/ehos-python.git
# Create a config file based on an existing openstack keystone file
./bin/ehos_create_config.py etc/ehos/ehos.yaml.template ~/[KEYSTONE-FILE]
This script configure and makes the openstack environment ready to run EHOS. The following steps are (or can be) preformed by the ehos_setup.py script: Automate the process of creating the image(s) on all region(s)/project(s) specified in your ehos.yaml file, this script will furthermore configure the firewall rules so the nodes can communicate together, upload a ssh key so you can connect to the master/execution node(s).
# setup the openstack specific requirements for running ehos.
# run ./bin/ehos_setup.py -h for all options
# The more -v's you add the more loggin will you get.
# Please be aware that this will take a few minuttes for each cloud to be initialised
# If you dont have an ssh key it is easy to generate:
ssh-keygen
# for a single region/private ehos:
./bin/ehos_setup.py --create-images --ssh-key ~/.ssh/id_rsa.pub etc/ehos/ehos.yaml
It is important that you have moved any modified config files into the etc directory as these will then automatically be copied across to the master node, along with the ehos.yaml file.
This script will install EHOS on the masternode. The commands to either run ehos-daemon on the commandline or as a systemd service is provided.
# create VM, install software, start EHOS. Again this will take upto 15 minuttes so be patient.
./bin/ehos_deployment.py etc/ehos/ehos.yaml
# This will print the IP address and ID for the master node.
# Please note this down as you will need to connect to the master
#Deactivate virtualenv:
deactivate
# logon to the master node, Note this might differ on your system!
ssh centos@[MASTER-NODE-IP]
# The ehos deamon needs to be run as root, so change to root with sudo
sudo -s
# start ehos-daemon manually:
# Start up the ehos sever, adding some -v will increase the logging amount:
/usr/local/bin/ehosd.py /usr/local/etc/ehos/ehos.yaml
To run is as a systemd service:
# or run it as as systemd service
systemctl enable ehos.service
systemctl start ehos.service
The EHOS package installs a script that is suitable for testing the EHOS installation. The script submits a set of jobs to the HTCondor queue that executes a sleep command on the execution nodes. Running the command without any parameters and you will get the full list of possible modifications as number of jobs, sleep intervals etc.
Note that this should be run on the master node, and cannot be run as root.
# Submit 10 jobs, sleeping randomly between 30 and 50 seconds
condor_run_jobs.py -n 10 -r 30,50
# Submit 10 jobs, each sleeping for 20 seconds
condor_run_jobs.py -n 10 -s 20
# expected output:
INFO:ehosd:Nr of jobs 12 (12 are queueing)
INFO:ehosd:We got stuff to do, creating some additional nodes...
WARNING:ehos:Could not create execute server
INFO:ehosd:Napping for 10 second(s).
INFO:ehosd:Nr of nodes 2 (0 are idle)
INFO:ehosd:Nr of jobs 12 (10 are queueing)
INFO:ehosd:We got stuff to do, creating some additional nodes...
WARNING:ehos:Could not create execute server
INFO:ehosd:Napping for 10 second(s).
INFO:ehosd:Nr of nodes 3 (0 are idle)
INFO:ehosd:Nr of jobs 10 (8 are queueing)
INFO:ehosd:We got stuff to do, creating some additional nodes...
WARNING:ehos:Could not create execute server
INFO:ehosd:Napping for 10 second(s).
INFO:ehosd:Nr of nodes 3 (0 are idle)
INFO:ehosd:Nr of jobs 8 (5 are queueing)
The system will leave some the image, some VM servers, firewall setting and keypairs behind after the test, these needs to be manually deleted.