How to configure xinetd?

xinetd Daemon

By default xinetd does not start automatically. You can find this service under /etc/init.d. To make xinetd daemon to start start automatically during boot, run insserv xinetd (or) chkconfig xinetd on

To start/stop/restart/reload xinetd, use rcxinetd command

Configuration

/etc/xinetd.conf is a default configuration file of xinetd. You may not need to make any changes in this file.

You can include dedicated configuration file for each service under /etc/xinetd.d folder.
Example configuration file for pop3

service pop3
{
port = 110
socket_type = stream
protocol = tcp
wait = no
user = root
server = /usr/sbin/popper
}

Few useful options are below:

instances = 30 #Maximum number of instaances
cps = 50 10 #50 connections per seconds, 10 seconds wait time after 50 connections.
only_from #allow from specific remote hosts
no_access #restrict access for specific remote hosts
access_time #service available time e.g. access_time 09:00-20:00
interface #specify which IP being used for xinetd when more than one interface used.

For more information man xinetd
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Topics will be covered in this Blog are : Linux System Administrator - Memory Performance Tuning - File System - User Group - Linux / Unix Commands Processes - Virtual Swap Memory - Mail Server - Remote Access - Linux Permissions - Boot procedure system Logging - Network (xinetd) Configuration (ifconfig) - DNS - DHCP - Web Server - Kernel - Shell Script - Tuning Optimization High Availability Heart-BeatClustering-Backup and Recovery - Network Time Protocol - NIS - NFS - RPM Partition - /proc - Scheduling (crontab) - mount unmount - secured shell (ssh) - Remote Access - Virtual Network Computing (VNC) Default Ports - Services
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why xinetd

The services can be fired when the system boots, which will occupy its respective ports and waiting for connections always. It will be using resources un-necessarily if the services will be used occasionally.

xinetd process run behalf of the services and it starts the process if any connection comes. So, it saves more system resources.

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Topics will be covered in this Blog are : Linux System Administrator - Memory Performance Tuning - File System - User Group - Linux / Unix Commands Processes - Virtual Swap Memory - Mail Server - Remote Access - Linux Permissions - Boot procedure system Logging - Network (xinetd) Configuration (ifconfig) - DNS - DHCP - Web Server - Kernel - Shell Script - Tuning Optimization High Availability Heart-BeatClustering-Backup and Recovery - Network Time Protocol - NIS - NFS - RPM Partition - /proc - Scheduling (crontab) - mount unmount - secured shell (ssh) - Remote Access - Virtual Network Computing (VNC) Default Ports - Services
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