我有一台机器运行 16.04 LTS。我尝试do-release-upgrade升级，但总是失败。最后我得到：
“按 x 键销毁窗口或按 r 键恢复窗口”
我正在寻找可能存在问题的线索。/var/log/dist-upgrade/main.log
# cat ./main.log 2019-04-16 17:29:25,723 INFO Using config files '['./DistUpgrade.cfg.xenial']' 2019-04-16 17:29:25,723 INFO uname information: 'Linux romulus 4.4.0-145-generic #171-Ubuntu SMP Tue Mar 26 12:43:40 UTC 2019 x86_64' 2019-04-16 17:29:26,162 INFO apt version: '1.2.31' 2019-04-16 17:29:26,163 INFO python version: '3.5.2 (default, Nov 12 2018, 13:43:14) [GCC 5.4.0 20160609]' 2019-04-16 17:29:26,167 INFO release-upgrader version '18.04.29' started 2019-04-16 17:29:26,181 INFO locale: 'en_US' 'UTF-8' 2019-04-16 17:29:26,257 DEBUG screen returned: 'There is a screen on: 4933.ubuntu-release-upgrade-screen-window (04/16/2019 02:10:26 PM)(Detached) 1 Socket in /var/run/screen/S-root. ' 2019-04-16 17:29:26,258 INFO found active screen session, re-attaching
答案1
事实证明，一些 Python 包不知何故损坏了。重新安装基本 Python 包以及与升级和包管理相关的包最终解决了这个问题。