Darn Simple Cloud

Cloud Services Installation

StratusLab provides a simple command line client to perform installation, configuration and startup of StratusLab Cloud services and components.

Default deployment assumes two types of machines:

  1. Front-End - cloud management server
  2. Node - host on which the virtual machines will be instantiated

By default the compute (OpenNebula) and disks management (Persistent Disk (PDisk)) services will be deployed on the Front-End. A set of packages will be installed on the Node(s) and then, the Node(s) will be configured and added to the manager of the compute resources on Front-End. By default KVM is used the Node(s).


  • hardware virtualization extensions has to be enabled in the BIOS on Node
  • CentOS 6.x on Front-End and Node
  • EPEL 6 repository enabled on Front-End
  • Python >= 2.6 and < 3.x on Front-End and Node
  • password-less SSH for root from Front-End to Node
  • password-less SSH for root from Front-End to Front-End
  • a block device (can be a loop device) to host LVM for VM images backend
  • a network bridge br0 configured on Node (for VM networks)
  • a default DHCP server must be configured to assign statically IP addresses corresponding to predictable MAC addresses. These IP addresses will require to be publicly visible if the cloud instances are to be accessible from the WAN.
  • hostname properly set on Front-End and Nodes otherwise some critical services cannot start properly
  • SELinux disabled in all nodes
  • StratusLab’s release yum repository properly set in all nodes
  • finally it’s recommended to do a yum -y update in all nodes before starting in order to install any critical updates and latest version of RPMs in the system

StratusLab Cloud Front-End Deployment

Deployment tool installation

First step is to install the StratusLab Cloud deployment command line client from StratusLab repository

yum install stratuslab-cli-sysadmin

Configuration file customization

The entire StratusLab Cloud is configured from a single configuration file /etc/stratuslab/stratuslab.cfg. StratusLab ships with a reference configuration file located in /etc/stratuslab/stratuslab.cfg.ref.

To help creating main configuration file from the reference one and manipulating its parameter values, one can use the command stratus-config.

To list the content of the configuration, and show the differences between the stratuslab.cfg file and the reference configuration, you can use the -k/-keys option:

stratus-config -k

To change a value, specify the key and the new value. To view a single value, simply specify the key.

VM Management Service

The following parameters are required to be set.

# Linux machine distribution
stratus-config frontend_system centos

# Front-End IP
stratus-config frontend_ip

# Public network for VMs
stratus-config one_public_network_addr ""
stratus-config one_public_network_mac "00:11:22:33:44:55 00:11:22:33:44:56"

In this example, the Front-End is configured on IP address, and two IP/MAC address pairs are defined, which must match the DHCP configuration.

More network parameters are described under the one-network section in the reference configuration file.

Disks Management Service

# Persistent Disk
stratus-config persistent_disk_system centos
stratus-config persistent_disk_ip

The Persistent Disk service and the Nodes communicate using a share strategy
defined by persistent_disk_storage and persistent_disk_share parameters. Provided the defaults are used (lvm for storage and iscsi for share), one needs to specify the following

stratus-config persistent_disk_physical_devices /dev/<BLOCK_DEVICE>

For details on configurable disks storage types and/or sharing mechanisms please check persistent-disks section of the reference configuration file.

Cloud Front-End Set-up

You can now set-up your StratusLab Cloud Front-End by simply issuing the following command


If errors occur, you can increase the verbosity level by adding -vv.

StratusLab Cloud Node Deployment

The deployment of the StratusLab Nodes is done from the Front-End, thus, all the commands below should be run from the Front-End.

To add a Node to the Cloud, specify the Linux distribution of the machine

stratus-config node_system centos

then invoke installation by

stratus-install -n <NODE_IP>

If errors occur, you can increase the verbosity level by adding -vv.