Part 3 of setting up a Linux home lab environment with VirtualBox. Check this blog post for more info.
NTP is used to synchronise the time on our Linux system with a centralised NTP server. A local NTP server on the network can be synchronised with an external timing source to keep all the servers in our organisation in-sync with an accurate time.
Software
Software used in this article:
- CentOS 6
- NTP 4.2
Intall and Configure an NTP Server
Install NTP package:
# yum install -y ntp
Open /etc/ntp.conf file for editing and add the following:
tinker panic 0 restrict default kod nomodify notrap nopeer noquery restrict -6 default kod nomodify notrap nopeer noquery restrict 127.0.0.1 restrict -6 ::1 server 0.uk.pool.ntp.org iburst server 1.uk.pool.ntp.org iburst server 2.uk.pool.ntp.org iburst server 3.uk.pool.ntp.org iburst driftfile /var/lib/ntp/drift
Server list may differ depending on your location.
Iptables will be configured via Puppet. The line below is used for the time being only:
# iptables -A INPUT -s 10.8.8.0/24 -p udp -m state --state NEW --dport 123 -j ACCEPT
Troubleshooting
Check logs:
# tail /var/log/messages