NTPサーバー
パッケージインストール
$ sudo dnf install ntp ntpdate
NTPサーバーの設定
設定ファイルのバックアップ。
$ sudo cp /etc/ntp.conf /etc/ntp.conf.org
設定ファイルの修正。
$ sudo vi /etc/ntp.conf
# Hosts on local network are less restricted. #restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap # Use public servers from the pool.ntp.org project. # Please consider joining the pool (http://www.pool.ntp.org/join.html). #pool 2.fedora.pool.ntp.org iburst pool ntp.jst.mfeed.ad.jp iburst # MFEED pool ntp.nict.jp iburst # NICT server s2csntp.miz.nao.ac.jp iburst # NAO pool ntp.ring.gr.jp iburst # Ring Server pool time.google.com iburst # Google
ファイヤーウォールの設定
$ sudo firewall-cmd --permanent --add-service=ntp
$ sudo firewall-cmd --reload
サービス自動起動設定
$ sudo systemctl enable ntpd.service
時刻の手動同期
サービスを起動する前に手動で同期しておく。
$ sudo ntpdate ntp.nict.jp
サービス起動
$ sudo systemctl start ntpd.service
動作確認
$ sudo ntpdate -d timeserver
10 Jan 01:42:07 ntpdate[2809]: ntpdate 4.2.8p12@1.3728-o Wed Aug 15 08:39:42 UTC 2018 (1)
Looking for host timeserver and service ntp
192.168.1.10 reversed to timeserver.tomoyan.local
host found : black-dc.tomoyan.local
transmit(192.168.1.10)
transmit(192.168.1.10)
receive(192.168.1.10)
receive: pkt.org and peer.xmt differ
receive(192.168.1.10)
transmit(192.168.1.10)
transmit(192.168.1.10)
receive(192.168.1.10)
receive: pkt.org and peer.xmt differ
receive(192.168.1.10)
server 192.168.1.10, port 123
stratum 2, precision -24, leap 00, trust 000
refid [133.243.238.163], root delay 0.034470, root dispersion 0.097672
transmitted 4, in filter 4
reference time: dfe02435.fe2f13ad Wed, Jan 9 2019 16:41:41.992
originate timestamp: dfe02455.9f9c7ecd Wed, Jan 9 2019 16:42:13.623
transmit timestamp: dfe0a2e5.fc372597 Thu, Jan 10 2019 1:42:13.985
filter delay: 0.00000 0.66539 0.00000 2.24023
0.00000 0.00000 0.00000 0.00000
filter offset: 0.000000 -32400.8 0.000000 -32401.4
0.000000 0.000000 0.000000 0.000000
delay 0.66539, dispersion 24.32080
offset -32400.827489
10 Jan 01:42:16 ntpdate[2809]: step time server 192.168.1.10 offset -32400.827489 sec
$ sudo ntpdate timeserver 9 Jan 16:55:00 ntpdate[8074]: adjust time server 192.168.1.10 offset -0.003202 sec