我们的一台网络服务器刚刚出了问题。它上面运行着几个 PHP 应用程序，并开始发出以下错误消息：
php_network_getaddresses: getaddrinfo failed: Name or service not known
此消息似乎与网络/dns 有关。服务器日志清楚地表明，在发生第一个错误时，Ubuntu 启动了一个unattended-upgrades会话。我将在下面附上输出dpkg.log。
我们使用外部数据库服务器。
我们决定重新启动网络服务器，这解决了该问题，但现在的问题是：
有什么方法可以让我找出这个问题的根本原因，以便将来能够预防它？
输出自无人值守升级.log：
2017-03-21 15:01:56,279 INFO Starting unattended upgrades script
2017-03-21 15:01:56,279 INFO Allowed origins are: ['o=Ubuntu,a=xenial', 'o=Ubuntu,a=xenial-security']
2017-03-21 15:02:03,365 INFO Packages that will be upgraded: libc-bin libc-dev-bin libc6 libc6-dev libfreetype6 locales multiarch-support
2017-03-21 15:02:03,365 INFO Writing dpkg log to '/var/log/unattended-upgrades/unattended-upgrades-dpkg.log'
2017-03-21 15:02:12,851 INFO All upgrades installed
输出自dpkg日志：
2017-03-21 15:02:03 startup archives unpack
2017-03-21 15:02:03 upgrade libc6-dev:amd64 2.23-0ubuntu5 2.23-0ubuntu6
2017-03-21 15:02:03 status half-configured libc6-dev:amd64 2.23-0ubuntu5
2017-03-21 15:02:03 status unpacked libc6-dev:amd64 2.23-0ubuntu5
2017-03-21 15:02:03 status half-installed libc6-dev:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status half-installed libc6-dev:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status unpacked libc6-dev:amd64 2.23-0ubuntu6
2017-03-21 15:02:04 status unpacked libc6-dev:amd64 2.23-0ubuntu6
2017-03-21 15:02:04 upgrade libc-dev-bin:amd64 2.23-0ubuntu5 2.23-0ubuntu6
2017-03-21 15:02:04 status half-configured libc-dev-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status unpacked libc-dev-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status half-installed libc-dev-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status triggers-pending man-db:amd64 2.7.5-1
2017-03-21 15:02:04 status half-installed libc-dev-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status unpacked libc-dev-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:04 status unpacked libc-dev-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:04 upgrade libc6:amd64 2.23-0ubuntu5 2.23-0ubuntu6
2017-03-21 15:02:04 status triggers-pending libc-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status half-configured libc6:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status unpacked libc6:amd64 2.23-0ubuntu5
2017-03-21 15:02:04 status half-installed libc6:amd64 2.23-0ubuntu5
2017-03-21 15:02:05 status half-installed libc6:amd64 2.23-0ubuntu5
2017-03-21 15:02:05 status unpacked libc6:amd64 2.23-0ubuntu6
2017-03-21 15:02:05 status unpacked libc6:amd64 2.23-0ubuntu6
2017-03-21 15:02:05 startup packages configure
2017-03-21 15:02:05 configure libc6:amd64 2.23-0ubuntu6 <none>
2017-03-21 15:02:05 status unpacked libc6:amd64 2.23-0ubuntu6
2017-03-21 15:02:05 status unpacked libc6:amd64 2.23-0ubuntu6
2017-03-21 15:02:05 status half-configured libc6:amd64 2.23-0ubuntu6
2017-03-21 15:02:05 status installed libc6:amd64 2.23-0ubuntu6
2017-03-21 15:02:05 trigproc libc-bin:amd64 2.23-0ubuntu5 <none>
2017-03-21 15:02:05 status half-configured libc-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:05 status installed libc-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:05 trigproc man-db:amd64 2.7.5-1 <none>
2017-03-21 15:02:05 status half-configured man-db:amd64 2.7.5-1
2017-03-21 15:02:05 status installed man-db:amd64 2.7.5-1
2017-03-21 15:02:05 startup archives unpack
2017-03-21 15:02:05 upgrade locales:all 2.23-0ubuntu5 2.23-0ubuntu6
2017-03-21 15:02:05 status half-configured locales:all 2.23-0ubuntu5
2017-03-21 15:02:05 status unpacked locales:all 2.23-0ubuntu5
2017-03-21 15:02:05 status half-installed locales:all 2.23-0ubuntu5
2017-03-21 15:02:06 status triggers-pending man-db:amd64 2.7.5-1
2017-03-21 15:02:06 status half-installed locales:all 2.23-0ubuntu5
2017-03-21 15:02:06 status unpacked locales:all 2.23-0ubuntu6
2017-03-21 15:02:06 status unpacked locales:all 2.23-0ubuntu6
2017-03-21 15:02:06 upgrade libc-bin:amd64 2.23-0ubuntu5 2.23-0ubuntu6
2017-03-21 15:02:06 status half-configured libc-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:06 status unpacked libc-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:06 status half-installed libc-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:06 status half-installed libc-bin:amd64 2.23-0ubuntu5
2017-03-21 15:02:06 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:06 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:06 trigproc man-db:amd64 2.7.5-1 <none>
2017-03-21 15:02:06 status half-configured man-db:amd64 2.7.5-1
2017-03-21 15:02:07 status installed man-db:amd64 2.7.5-1
2017-03-21 15:02:07 startup packages configure
2017-03-21 15:02:07 configure libc-bin:amd64 2.23-0ubuntu6 <none>
2017-03-21 15:02:07 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status unpacked libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status half-configured libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status installed libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 startup archives unpack
2017-03-21 15:02:07 upgrade multiarch-support:amd64 2.23-0ubuntu5 2.23-0ubuntu6
2017-03-21 15:02:07 status half-configured multiarch-support:amd64 2.23-0ubuntu5
2017-03-21 15:02:07 status unpacked multiarch-support:amd64 2.23-0ubuntu5
2017-03-21 15:02:07 status half-installed multiarch-support:amd64 2.23-0ubuntu5
2017-03-21 15:02:07 status half-installed multiarch-support:amd64 2.23-0ubuntu5
2017-03-21 15:02:07 status unpacked multiarch-support:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status unpacked multiarch-support:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 startup packages configure
2017-03-21 15:02:07 configure multiarch-support:amd64 2.23-0ubuntu6 <none>
2017-03-21 15:02:07 status unpacked multiarch-support:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status half-configured multiarch-support:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status installed multiarch-support:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 startup archives unpack
2017-03-21 15:02:07 upgrade libfreetype6:amd64 2.6.1-0.1ubuntu2 2.6.1-0.1ubuntu2.1
2017-03-21 15:02:07 status triggers-pending libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status half-configured libfreetype6:amd64 2.6.1-0.1ubuntu2
2017-03-21 15:02:07 status unpacked libfreetype6:amd64 2.6.1-0.1ubuntu2
2017-03-21 15:02:07 status half-installed libfreetype6:amd64 2.6.1-0.1ubuntu2
2017-03-21 15:02:07 status half-installed libfreetype6:amd64 2.6.1-0.1ubuntu2
2017-03-21 15:02:07 status unpacked libfreetype6:amd64 2.6.1-0.1ubuntu2.1
2017-03-21 15:02:07 status unpacked libfreetype6:amd64 2.6.1-0.1ubuntu2.1
2017-03-21 15:02:07 trigproc libc-bin:amd64 2.23-0ubuntu6 <none>
2017-03-21 15:02:07 status half-configured libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status installed libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 startup packages configure
2017-03-21 15:02:07 configure libc-dev-bin:amd64 2.23-0ubuntu6 <none>
2017-03-21 15:02:07 status unpacked libc-dev-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status half-configured libc-dev-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status installed libc-dev-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 configure libc6-dev:amd64 2.23-0ubuntu6 <none>
2017-03-21 15:02:07 status unpacked libc6-dev:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status half-configured libc6-dev:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 status installed libc6-dev:amd64 2.23-0ubuntu6
2017-03-21 15:02:07 configure locales:all 2.23-0ubuntu6 <none>
2017-03-21 15:02:07 status unpacked locales:all 2.23-0ubuntu6
2017-03-21 15:02:07 status unpacked locales:all 2.23-0ubuntu6
2017-03-21 15:02:07 status half-configured locales:all 2.23-0ubuntu6
2017-03-21 15:02:11 status installed locales:all 2.23-0ubuntu6
2017-03-21 15:02:11 configure libfreetype6:amd64 2.6.1-0.1ubuntu2.1 <none>
2017-03-21 15:02:11 status triggers-pending libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:11 status unpacked libfreetype6:amd64 2.6.1-0.1ubuntu2.1
2017-03-21 15:02:11 status half-configured libfreetype6:amd64 2.6.1-0.1ubuntu2.1
2017-03-21 15:02:11 status installed libfreetype6:amd64 2.6.1-0.1ubuntu2.1
2017-03-21 15:02:11 trigproc libc-bin:amd64 2.23-0ubuntu6 <none>
2017-03-21 15:02:11 status half-configured libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:11 status installed libc-bin:amd64 2.23-0ubuntu6
2017-03-21 15:02:11 startup packages configure
答案1
我们发现这种情况影响了我们的环境，5 小时后又再次发生。考虑回滚到旧版本的 libc6 补丁。
以下是此问题的 Ubuntu 错误，它证实了我们所看到的情况：https://bugs.launchpad.net/ubuntu/+source/eglibc/+bug/1674532
更新：该问题已得到修复。
看评论#16，#17和#18在上述报告中。更新libc应该可以解决该问题。建议重新启动以确保在更新期间使用此库的任何正在运行的进程保持正常运行。