Review your favorite Linux distribution.
Go Back > Forums > Linux Forums > Linux - Newbie
User Name
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!


  Search this Thread
Old 08-26-2018, 02:57 PM   #1
LQ Newbie
Registered: Aug 2018
Posts: 1

Rep: Reputation: Disabled
Clients not updating with NTP server


I'm running an NTP servers on Centos 7. This NTP server is synchronizing ok with external NTP servers, but clients (Windows and Linux) are not getting their times updated by the Centos Server. Below is my ntp.conf file. Firewall is not enabled on the Centos box. Can someone tell me if I'm missing something?

cat /etc/ntp.conf
# For more information about this file, see the man pages
# ntp.conf(5), ntp_acc(5), ntp_auth(5), ntp_clock(5), ntp_misc(5), ntp_mon(5).

driftfile /var/lib/ntp/drift

# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.
restrict default nomodify notrap nopeer noquery

# Permit all access over the loopback interface. This could
# be tightened as well, but to do so would effect some of
# the administrative functions.
restrict ::1

# Hosts on local network are less restricted.
restrict 172.X.X.0 mask nomodify notrap
broadcast 172.X.X.255 autokey

# Use public servers from the project.
# Please consider joining the pool (
#server iburst
#server iburst
#server iburst
#server iburst


#broadcast autokey # broadcast server
#broadcastclient # broadcast client
#broadcast autokey # multicast server
#multicastclient # multicast client
#manycastserver # manycast server
#manycastclient autokey # manycast clien

# Enable public key cryptography.

includefile /etc/ntp/crypto/pw

# Key file containing the keys and key identifiers used when operating
# with symmetric key cryptography.
keys /etc/ntp/keys

# Specify the key identifiers which are trusted.
#trustedkey 4 8 42

# Specify the key identifier to use with the ntpdc utility.
#requestkey 8

# Specify the key identifier to use with the ntpq utility.
#controlkey 8

# Enable writing of statistics records.
#statistics clockstats cryptostats loopstats peerstats

# Disable the monitoring facility to prevent amplification attacks using ntpdc
# monlist command when default restrict does not include the noquery flag. See
# CVE-2013-5211 for more details.
# Note: Monitoring will not be disabled with the limited restriction flag.
disable monitor
Old 08-27-2018, 02:19 AM   #2
Honest Abe
Registered: May 2018
Distribution: CentOS 7, OpenSUSE 15
Posts: 330
Blog Entries: 1

Rep: Reputation: 161Reputation: 161
Looks like this is your ntp.conf file from the intended NTP server (which syncs with ).

For your intended clients, you should use the above server's IP. (preferably with iburst).

So, please show us the ntp.conf file from your clients.. or show us outputs of the following from your clients -

ntpdate -q <your NTP server IP>
ntpq -p
Also, have you already looked here ?

Last edited by Honest Abe; 08-30-2018 at 12:48 AM.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
LXer: Install and configure Network Time Protocol (NTP) Server,Clients on Ubuntu 16.04 Server LXer Syndicated Linux News 0 10-12-2016 01:24 PM
Have set-up ntp server - seems to be ok but clients cannot sync juro0304 Linux - Networking 1 06-04-2015 06:07 AM
NTP clients are updating very slow sanjusharma Linux - Newbie 1 02-08-2013 07:25 AM
ntp server cannot sync clients NdAd Linux - Software 22 07-15-2010 12:13 AM
[SOLVED] NTP config - how to prevent clients using my server? ShadyCraig Linux - Server 1 05-24-2010 08:55 AM > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 01:25 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration