Moxa DA-685-LX [11/76] Attention

DA-685 Linux Software Configuration

2-6

ATTENTION

Before using the NTP client utility, check your IP address and network settings (gateway and DNS) to make

sure an Internet connection is available.

Updating the Time Automatically

This section describes how to use a shell script to update the time automatically.

Example shell script for updating the system time periodically

#!/bin/sh

ntpdate time.stdtime.gov.tw

# You can use the time server’s ip address or domain

# name directly. If you use domain name, you must

# enable the domain client on the system by updating

# /etc/resolv.conf file.

hwclock –w

sleep 100

# Updates every 100 seconds. The min. time is 100 seconds.

# Change 100 to a larger number to update RTC less often.

Save the shell script using any file name. For example, fixtime.

How to run the shell script automatically when the kernel boots up

Because the root file system is mounted in Read-only mode, we need to re-mount it using writable permission.

# mount -o remount,rw /dev/hda1 /

Copy the example shell script fixtime to directory /etc/init.d, and then use chmod 755 fixtime to change

the shell script mode.

# chmod 755 fixtime

Next, use vi editor to edit the file /etc/inittab.

# vi /etc/inittab

Add the following line to the bottom of the file:

ntp : 2345 : respawn : /etc/init.d/fixtime

After you finish writing or modifying the code, remember to execute “umount /” to change the root directory

back to Read-only mode.

# umount /

Use the command #init q to re-initialize the kernel.

# init q

Enabling and Disabling Daemons

The following daemons are enabled when the DA-685-LX boots up for the first time.

snmpd SNMP Agent Daemon

telnetd Telnet Server/Client Daemon