Difference between revisions of "Ntp"

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When using an NTP-server pool like [https://pool.ntp.org pool.ntp.org] ( 0.<country>.pool.ntp.org etc.) make sure you refresh the peers every now and than. Only when ntp is started the hosts are selected, when they leave the pool ntp will not automatically select another.
 
When using an NTP-server pool like [https://pool.ntp.org pool.ntp.org] ( 0.<country>.pool.ntp.org etc.) make sure you refresh the peers every now and than. Only when ntp is started the hosts are selected, when they leave the pool ntp will not automatically select another.
 +
 +
;Very secure setinngs in ntp.conf
 +
restrict -4 default kod nomodify notrap nopeer noquery
 +
restrict -6 default kod nomodify notrap nopeer noquery

Revision as of 09:24, 21 January 2021

Network Time Protocol, synchronize local clock to remote.

To use ntpq the firewall should be open for traffic to the localhost.

iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT
ip6tables -A INPUT -i lo -j ACCEPT
ip6tables -A OUTPUT -o lo -j ACCEPT

When using an NTP-server pool like pool.ntp.org ( 0.<country>.pool.ntp.org etc.) make sure you refresh the peers every now and than. Only when ntp is started the hosts are selected, when they leave the pool ntp will not automatically select another.

Very secure setinngs in ntp.conf
restrict -4 default kod nomodify notrap nopeer noquery
restrict -6 default kod nomodify notrap nopeer noquery