我的 SES 设置在过去 6 个月内运行良好，没有任何问题。昨天突然停止工作，我收到了臭名昭著的时间同步错误。
我自然而然地认为 ntpd 已经停止了，但令我惊讶的是，当我检查进程树时，我注意到它正在运行。
~ ps auwx | grep ntpd
ntp 18223 0.0 0.0 33600 2132 ? Ss 07:05 0:00 /usr/sbin/ntpd -p /var/run/ntpd.pid -g -u 106:112
ubuntu 19127 0.0 0.0 8144 668 pts/5 S+ 07:19 0:00 grep ntpd
然后我尝试ntpdate说
2 Sep 07:16:09 ntpdate[18966]: no servers can be used, exiting
我检查了/etc/ntp.conf默认列出默认 ubuntu 服务器的文件。
# /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help
driftfile /var/lib/ntp/ntp.drift
# Enable this if you want statistics to be logged.
#statsdir /var/log/ntpstats/
statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable
# Specify one or more NTP servers.
# Use servers from the NTP Pool Project. Approved by Ubuntu Technical Board
# on 2011-02-08 (LP: #104525). See http://www.pool.ntp.org/join.html for
# more information.
server 0.ubuntu.pool.ntp.org
server 1.ubuntu.pool.ntp.org
server 2.ubuntu.pool.ntp.org
server 3.ubuntu.pool.ntp.org
# Use Ubuntu's ntp server as a fallback.
server ntp.ubuntu.com
# Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for
# details. The web page <http://support.ntp.org/bin/view/Support/AccessRestrictions>
# might also be helpful.
#
# Note that "restrict" applies to both servers and clients, so a configuration
# that might be intended to block requests from certain clients could also end
# up blocking replies from your own upstream servers.
# By default, exchange time with everybody, but don't allow configuration.
restrict -4 default kod notrap nomodify nopeer noquery
restrict -6 default kod notrap nomodify nopeer noquery
# Local users may interrogate the ntp server more closely.
restrict 127.0.0.1
restrict ::1
# Clients from this (example!) subnet have unlimited access, but only if
# cryptographically authenticated.
#restrict 192.168.123.0 mask 255.255.255.0 notrust
# If you want to provide time to your local subnet, change the next line.
# (Again, the address is an example only.)
#broadcast 192.168.123.255
# If you want to listen to time broadcasts on your local subnet, de-comment the
# next lines. Please do this only if you trust everybody on the network!
#disable auth
#broadcastclient
我没能在这里发现问题。然后我尝试检查 NTP 服务器的状态，发现没有问题。
/etc/init.d/ntp status
* NTP server is running
我还尝试手动添加 NTP 服务器，看看是否有效，但这也无济于事
sudo ntpdate ntp.ubuntu.com
2 Sep 07:20:08 ntpdate[19203]: the NTP socket is in use, exiting
我真的不明白这里的问题是什么。为什么 ntpd 在后台运行时不工作？
任何帮助都将不胜感激。谢谢。
答案1
ntpd跑步之前你需要停下来ntpdate。
sudo service ntp stop
sudo ntpdate 0.ubuntu.pool.ntp.org
sudo service ntp start
答案2
在 Ubuntu 上你应该使用
ntpd -q
而不是ntpdate如果你已经安装了ntpd
手册页：
-q Exit the ntpd just after the first time the clock is set. This behavior mimics that of the ntpdate program, which is to be retired.
The -g and -x options can be used with this option. Note: The kernel time discipline is disabled with this option.