Newbie documentation - What you should know

OCS Inventory NG in 5 lines, what is it ?

OCS Inventory NG or Open Computer and Software Inventory Next Generation is free software that enables users to automatically inventory their IT assets. OCS-NG collects information about the hardware and software of networked machines running the OCS client program ("OCS Inventory Agent"). OCS can be used to visualize the inventory through a web interface. Furthermore, OCS allows the possibility of deploying applications on the computers according to search criteria. Agent-side IpDiscover and snmp scan make it possible to identify the entire network of computers and devices.

Operating principle

The OCS server receives inventories which are sent by agents in XML format, and stored data in MySQL database. The Agents contact the server. The server only listens during this process. Exchanges between agents and server are made in http and/or https. Software deployments and snmp scans are made in https only.

Schema of data transmission:

Rawdata->XMLformatting -> sending in HTTP or HTTPS in/ocsinventory-> handling withmod_perlon the fly -> DBmysql

Management server is made up of 4 main components:

  1. Database server, which stores inventory information (mysql)
  2. Communication server, which handles HTTP communications between database server and agents (Apache, perl and mod_perl)
  3. Administration console, which allows administrators to query the database server using their favorite browser (Apache, php)
  4. Deployment server, which stores all package deployment configuration (Apache, ssl)

OCS Inventory Structure Diagram

Deployment tools of the solution

Simplified installation of server

  • .deb package with automatic install script for Debian 9 Stretch
  • .rpm package with automatic install script for Fedora/Redhat/Centos 7

Deployment tools of agents by the network

Interfacing with many softwares


  • GLPI
  • LDAP
  • ITOP
  • OTRS


OCS provides a REST API, which allows it to interface with many applications, such as Nagios for example.

Major technical information

Windows agent

Agent configuration directory: C:\Documents and Settings\All Users\Application Data\OCS Inventory NG\Agent under Windows 2000, XP and 2003. C:\ProgramData\OCS Inventory NG\Agent under Windows Vista, 2008, Seven and 2008 R2. Agent configuration file is ocsinventory.ini


Do not confuse directories /ocsinventory and /ocsreports. ocsreports : directory containing all the php files that make up the administration console. ocsinventory : virtual directory used by mod_perl to handle XML inventories files sent by agents and to store data in database.

Debug the solution

  • Using agents logs:
    • Windows : Use Debug parameter in ocsinventory.ini file to have more verbose logs (Debug=2). This config file is located in:
      • C:\Documents and Settings\All Users\Application Data\OCS Inventory NG\Agent for Windows 2000, XP et 2003.
      • C:\ProgramData\OCS Inventory NG\Agent for Windows Vista, 2008, Seven et 2008 R2. You have first to stop OCS service if OCS is installed as a service. Then, set Debug=2 to obtain the higher log level and save. Finally, restart OCS service, and send a new inventory.
    • Unix/Linux : Use --debug and --logfile parameters to obtain a detailed log. Launch inventory with these options : ocsinventory-agent --debug --logfile=/mon/path/log.txt
  • Using server log:
    • Apache logs : access.log and error.log. To found it use locate or find commands.
    • OCS log : activity.log To use this functionality, you have to activate log function from administration console (LOGLEVEL), and modify server configuration file z-ocsinventory-server.conf to set OCS_OPT_DBI_PRINT_ERROR option to 1. Remember to restart apache to reflect this change.