Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Script to detect time drift
Operating Systems HP-UX Script to detect time drift Post 303017325 by rbatte1 on Monday 14th of May 2018 07:32:47 AM
Old 05-14-2018
You would have to do this on the client side. If you have a problem with your NTP time server, then treat that as the client and get it to align to another trusted clock, be that a radio-clock or internet address.

You can also use ntpdate -d refer-server to get a time difference from the reference server (which must be offering the NTP service, of course)

if the clock drift is too far, then you would need to step the clock on the local server to match something like this:-
  • Check the offset with - ntpdate -d ref-server
  • Stop the local NTP service in the normal way
  • Step the clock into sync - ntpdate ref-server
  • Start the local service in the normal way
  • Check the offset with - ntpdate -d ref-server

You should see debug information when you use the -d flag and the last line gives you the agreed offset from the reference server or servers (just a space separated list)


If you can't have the NTP client running all the time because your application doesn't like the clock going backwards even by tiny fractions of a second, you would probably need to schedule and idle minute to step the clock each day. You can run ntpdate -d ref-server at any time and just use the last line to show you the current offset from the trusted clock.



I hope that this helps,
Robin
 

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

how to detect my script is already running

I have a script which must not be run more than once at any given time. THis script will be scheduled to run every 20 mins as a cron job. In my script can i have logic to say if this script is already running from the previous cron, then exit. How do i go about doing that. If you describe the... (11 Replies)
Discussion started by: rmulchandani
11 Replies

2. Shell Programming and Scripting

AWK script to detect webpages from file

Hi guys I'm very new to unix and I have to create an awk script that detects webpage addresses from a file/webpage and outputs how many times each webpage was detected.e.g. if my file was: (Note: The symbol " was added to stop them being created into links) "www.google.com"... (1 Reply)
Discussion started by: ROFL
1 Replies

3. Shell Programming and Scripting

AWK script to detect webpages from file

Hi guys I'm very new to unix and I have to create an awk script that detects webpage addresses from a file/webpage and outputs how many times each webpage was detected.e.g. if my file was: www.google.com www.facebook.com www.google.com the output should be: www.google.com x2... (2 Replies)
Discussion started by: ROFL
2 Replies

4. Shell Programming and Scripting

Detect if script starts from queue

Dear community, what I'm try to do is deny users to run a script without parameters from command bash, but the same script should run without parameters only from crontab. Example runs by crontab:*/5 * * * * /tmp/script.sh Here the normal execution starts every 5 minutes Example #1 runs by... (16 Replies)
Discussion started by: Lord Spectre
16 Replies

5. Shell Programming and Scripting

How to detect Hanged process in shell script?

I have to check daily 20 processes each day. The names are like Network1 Network2 Network3 ....... Network20. There is built in utility for doing this. Following is the command to check a single network process. check_process_status 1 If we want to check the status of Network2 then the... (6 Replies)
Discussion started by: Nakul_sh
6 Replies

6. Shell Programming and Scripting

Help with detect with regex and move script

Hi all, I am needing some help with a script that will search for a video file by known extensions and then do a pattern search (I'm guessing via regex) and then based on a match of one type of another move the file to an assigned directory. I would like to do this with either a shell script... (7 Replies)
Discussion started by: Simplify
7 Replies

7. UNIX for Advanced & Expert Users

A script to detect system type

Hi forum, So I am trying to determine the OS type with the following script: #!/usr/bin/sh OStype1=`uname -s` Sunos1=SunOs if then echo "This system is Linux" exit 0 elif then echo "This system is SunOs" exit 0 elif (1 Reply)
Discussion started by: dampio
1 Replies

8. UNIX for Beginners Questions & Answers

Script to detect time drift on server

Hello there, I am not an expert in networking related stuff but I got a requirement to create UNIX script to query our Company's internal time source via NTP for time drift detect and report it when > +/- 50ms. I have been googling a lot but thought to post it in this forum to get a... (1 Reply)
Discussion started by: Green_Star
1 Replies

9. Shell Programming and Scripting

How to detect url in use in a script?

Hello, I have a small script and it runs from web application in below format: pipe:///path_to_myscript.sh url1 url2 url3 myscript.sh: #!/bin/bash count=0 while do count=$((count+1)) exec 3>&1 ((ffmpeg -i $1 ...... -f mpegts pipe:1 2>/dev/null 1>&3 ) 2>&1 | \ while read LINE; do echo... (9 Replies)
Discussion started by: baris35
9 Replies

LEARN ABOUT ULTRIX

ntp.conf

ntp.conf(5)							File Formats Manual						       ntp.conf(5)

Name
       ntp.conf - Network Time Protocol configuration file

Description
       The  file  is the configuration file for the Network Time Protocol (NTP) daemon, This file must be configured on your system before running
       Any host names that you specify in the file must have an entry in the file, or an entry in the master database, if the  database  is  being
       served to your system by BIND/Hesiod or Yellow Pages.

       The file has four entry formats:

       trusting no
	    This entry guarantees that your system synchronizes only to the NTP servers identified in the peer and server entries specified.  Dig-
	    ital recommends that all systems include the entry.

       peer server
	    This entry identifies server as one of the NTP servers that your system trusts, and from which your system will accept  time  synchro-
	    nization.	 Your  system  may  also  provide time synchronization to this server.	Servers can be identified by host name or internet
	    address.

	    NTP servers should be configured with entries.

       server server
	    This entry identifies server as one of the NTP servers that your system trusts, and from which your system will accept  time  synchro-
	    nization.	Your  system  can  not	provide  time  synchronization to this server.	Servers can be identified by host name or internet
	    address.

	    NTP clients should be configured with entries.

       peer   /dev/null       LOCL    1       -5      local
	    This entry identifies your system as a local reference clock.  A local reference clock is the most accurate system clock available	at
	    your  site.   If you receive time synchronization from the Internet NTP service, you should not include this entry on any of your sys-
	    tems.  At most, one system in a set of nodes running should be identified as a local reference clock.

	    A host which specifies this entry should not specify any or entries.

Examples
       This is a sample configuration file for an NTP client which receives time synchronization from the NTP servers: and Lines beginning with  a
       number sign (#) are comments.
       #
       #	       NTP  Configuration File
       #	This file is mandatory for the ntpd daemon
       #
       #
       #
       #   **  A L L  **
       #
       #  "trusting no" prevents this host from synchronizing
       #   to any host that is not listed below.  It is recommended
       #   that all hosts include the line "trusting no".
       #
       trusting no
       #
       #
       #    **	S E R V E R  **
       #
       #  If you are configuring a server, use "peer" entries to
       #  synchronize to other NTP servers.  For example, server1,
       #  server2, and server3.
       #
       #peer	      server1
       #peer	      server2
       #peer	      server3
       #
       #
       #
       #
       #    **	C L I E N T  **
       #
       #  If you are configuring a client, use "server" entries to
       #  synchronize to NTP servers.  For example, server1, server2,
       #  and server3.
       #
       server	      server1
       server	      server2
       server	      server3
       #
       #
       #
       #    **	L O C A L   R E F E R E N C E	C L O C K  **
       #
       #  If you are configuring a local reference clock, include the
       #  following entry and the "trusting no" entry ONLY.
       #
       #peer	 /dev/null LOCL 1    -5   local
       #

See Also
       ntp(1), ntpd(8), ntpdc(8)
       RFC 1129--Internet time synchronization:  The Network Time Protocol
       Introduction to Networking and Distributed System Services

																       ntp.conf(5)
All times are GMT -4. The time now is 07:46 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy