Servers time syncronization

Posted on 2004-11-05
Medium Priority
Last Modified: 2013-12-27

We have two unix server, I'd like server A to sync with an outside time server, while server B sync to A. What are the possible approaches? How about:

1. run xntpd on both A and B; stop xntpd to run ntpdate outside_servername and then restart xntpd

2. run ntpdate on A, run rdate on B

What else?

Question by:ebi168
LVL 40

Assisted Solution

jlevie earned 210 total points
ID: 12509680
Run xntpd on both. Set up A to sync to an Internet time keeper and permit/configure B to sync to A.
LVL 38

Accepted Solution

wesly_chen earned 300 total points
ID: 12510025

   My personal experience for 2 unix servers, I perfer "2"
On A
# crontab -e
1 * * * * ntpdate <internet ntp server ip>

On B
# crontab -e
2 * * * * ntpdate A

   xntpd have some limitation such as time offset more than 18 minutes (?) will fail to sync the time.
Besides, xntpd might have some issues sometimes.

LVL 38

Assisted Solution

yuzh earned 240 total points
ID: 12511352
I would go for option 2). and use cron to run ntpdate on A, run rdate on B.

Box A get time from an  NTP server.

Featured Post

Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

A metadevice consists of one or more devices (slices). It can be expanded by adding slices. Then, it can be grown to fill a larger space while the file system is in use. However, not all UNIX file systems (UFS) can be expanded this way. The conca…
FreeBSD on EC2 FreeBSD (https://www.freebsd.org) is a robust Unix-like operating system that has been around for many years. FreeBSD is available on Amazon EC2 through Amazon Machine Images (AMIs) provided by FreeBSD developer and security office…
Learn how to get help with Linux/Unix bash shell commands. Use help to read help documents for built in bash shell commands.: Use man to interface with the online reference manuals for shell commands.: Use man to search man pages for unknown command…
This video shows how to set up a shell script to accept a positional parameter when called, pass that to a SQL script, accept the output from the statement back and then manipulate it in the Shell.
Suggested Courses

862 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question