Linux/CentOSのntp.conf

CentOSのntp.conf †

ntpdを動かす場合 †

ntpdはシステムに影響を与えない為、少しずつ時刻合わせを行います。

初めに起動する場合は、ntpdate コマンドで時刻合わせしてから起動するのをお勧めします。

# cat /etc/ntp.conf

# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.
restrict default kod 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 127.0.0.1 

# Hosts on local network are less restricted.
#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).

#broadcast 192.168.1.255 key 42                # broadcast server
#broadcastclient                       # broadcast client
#broadcast 224.0.1.1 key 42            # multicast server
#multicastclient 224.0.1.1             # multicast client
#manycastserver 239.255.254.254                # manycast server
#manycastclient 239.255.254.254 key 42 # manycast client

# Undisciplined Local Clock. This is a fake driver intended for backup
# and when no outside source of synchronized time is available. 
server 127.127.1.0
fudge  127.127.1.0 stratum 10  

# Drift file.  Put this in a directory which the daemon can write to.
# No symbolic links allowed, either, since the daemon updates the file
# by creating a temporary in the same directory and then rename()'ing
# it to the file.
driftfile /var/lib/ntp/drift

# 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
server ntp1.jst.mfeed.ad.jp
restrict ntp1.jst.mfeed.ad.jp mask 255.255.255.255 nomodify notrap noquery
server ntp2.jst.mfeed.ad.jp
restrict ntp2.jst.mfeed.ad.jp mask 255.255.255.255 nomodify notrap noquery
server ntp3.jst.mfeed.ad.jp
restrict ntp3.jst.mfeed.ad.jp mask 255.255.255.255 nomodify notrap noquery