无论我尝试什么，似乎都无法运行 apt-get 命令来删除一个软件包（在本例中为 nginx），然后安装一个带有一些更新的软件包（nginx-extras）并完成升级。
我知道人们会说“这很危险”，但这些都是我的服务器，我正尝试同时在自己的多台服务器上运行此程序。为什么不起作用？
不起作用，系统日志中不显示任何内容（但 cron 作业可以正确启动）。
并且已经尝试添加--force-yes但没有帮助......
以下命令位于类似“my-shell-script”的文件中，该文件在 root crontab 中每小时调用一次：
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" remove nginx
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" update
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" add-apt-repository ppa:nginx/development
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" update
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" install nginx-extras
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" update
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" upgrade
更新：不确定，但我认为在管道到 syslog 之后我找到了正确的 crontab 日志：
Reading package lists...
Building dependency tree...
Reading state information...
The following packages will be REMOVED:
nginx
0 upgraded, 0 newly installed, 1 to remove and 3 not upgraded.
After this operation, 35.8 kB disk space will be freed.
dpkg: warning: 'ldconfig' not found in PATH or not executable
dpkg: warning: 'start-stop-daemon' not found in PATH or not executable
dpkg: error: 2 expected programs not found in PATH or not executable
Note: root's PATH should usually contain /usr/local/sbin, /usr/sbin and /sbin
E: Sub-process /usr/bin/dpkg returned an error code (2)
Hit:1 http://archive.ubuntu.com/ubuntu xenial InRelease
Get:2 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB]
Hit:4 http://ppa.launchpad.net/nginx/development/ubuntu xenial InRelease
Get:5 http://archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB]
Fetched 306 kB in 1s (255 kB/s)
Reading package lists...
E: Command line option --yes is not understood in combination with the other options
Hit:1 http://archive.ubuntu.com/ubuntu xenial InRelease
Get:2 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]
Hit:3 http://ppa.launchpad.net/nginx/development/ubuntu xenial InRelease
Get:4 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB]
Get:5 http://archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB]
Fetched 306 kB in 1s (200 kB/s)
Reading package lists...
Reading package lists...
Building dependency tree...
Reading state information...
The following additional packages will be installed:
libhiredis0.13 libluajit-5.1-2 libluajit-5.1-common
libnginx-mod-http-cache-purge libnginx-mod-http-fancyindex
libnginx-mod-http-headers-more-filter libnginx-mod-http-lua
libnginx-mod-http-ndk libnginx-mod-http-perl
libnginx-mod-http-uploadprogress libnginx-mod-nchan
Suggested packages:
nginx-doc
The following packages will be REMOVED:
nginx-full
The following NEW packages will be installed:
libhiredis0.13 libluajit-5.1-2 libluajit-5.1-common
libnginx-mod-http-cache-purge libnginx-mod-http-fancyindex
libnginx-mod-http-headers-more-filter libnginx-mod-http-lua
libnginx-mod-http-ndk libnginx-mod-http-perl
libnginx-mod-http-uploadprogress libnginx-mod-nchan nginx-extras
0 upgraded, 12 newly installed, 1 to remove and 3 not upgraded.
Need to get 0 B/1,228 kB of archives.
After this operation, 2,141 kB of additional disk space will be used.
dpkg: warning: 'ldconfig' not found in PATH or not executable
dpkg: warning: 'start-stop-daemon' not found in PATH or not executable
dpkg: error: 2 expected programs not found in PATH or not executable
Note: root's PATH should usually contain /usr/local/sbin, /usr/sbin and /sbin
E: Sub-process /usr/bin/dpkg returned an error code (2)
Hit:1 http://ppa.launchpad.net/nginx/development/ubuntu xenial InRelease
Hit:2 http://archive.ubuntu.com/ubuntu xenial InRelease
Get:3 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]
Get:4 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB]
Get:5 http://archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB]
Fetched 306 kB in 1s (267 kB/s)
Reading package lists...
Reading package lists...
Building dependency tree...
Reading state information...
Calculating upgrade...
The following packages have been kept back:
linux-generic linux-headers-generic linux-image-generic
0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.
答案1
感谢@steeldriver 指出正确的方向。我的脚本只需要PATH在每个命令上定义，而不仅仅是upgrade命令（最初只在最后一行）。
现在已经确认它可以自动运行，是的，我遇到的几乎所有 cron 作业问题都是由路径或相对路径引起的。谢谢！
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" remove nginx
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" update
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" add-apt-repository ppa:nginx/development
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" update
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" install nginx-extras
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" update
DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' /usr/bin/apt-get -q --yes -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" upgrade