ORBIT Services

The services and software running on each of the two servers is listed below. Configuration of individual services is explained in detail as well

Service name

DHCP

DNS

NTP

TFTP

PXE

Frisbee

NFS

Apt

Mysql

OML collection server

Apache

DHCP

Purpose: This software runs a DHCP server that assigns IP addresses to clients on demand

DNS

Purpose: Services.orbit-lab.org” hosts the primary DNS service for the zone orbit-lab.org. The DNS server is the standard BIND9 software packaged with Linux

Apache Web Server

Purpose: Apache server is required for maintaining the ORBIT local repository for debian packages and also to view the results of the experiment

Repository

Purpose: This serves as the debian package repository for local ORBIT packages (such as OML, OTG, Libmac, nodeAgent etc). It uses apache services to fetch and distribute debian packages. For this service, it is sufficient to install just the ORBIT packages. There is no need to mirror the entire debian repository which can be easily accessed by syncing with the external debian repository.

NTP

Purpose:

All the machines synchronize their time using the time server as the reference.

TFTP Server

Purpose: TFTP is needed to install PXE images whenever you need to install an image onto the node (using Frisbee). It is also used to load a memory based image that can be used to fetch the current image of the node into the repository

NFS Service

Purpose: This service is used to remotely mount directories on the nodes while fetching their image using imagezip utility. Also, Frisbee service makes use of this directory to install images onto nodes.

Mysql Server

Purpose: This service is used to store the results of the experiments conducted on ORBIT

OML Server (Collection Server)

Purpose:

This service is used to collect the measurements of the experiments at runtime from the nodes and store them into the mysql database.

Installation:

apt-get install oml-collection-server

Configuration:

This service is configured by the corresponding gridservice.

Gridservices

Purpose:

This service is for fetching and installing images from and to the nodes and used the Frisbee utility from University of Utah to distribute the image in the form of chunks using multicast.

Node Handler (runs on console.orbit-lab.org)

Purpose: NodeHandler is used to run the experiments from the console using reliable multicast to disseminate commands to the nodes. It also initializes measurement collection appropriately. It primarily uses ruby scripts to do the same.