2020-02-21 15:40:19,744 INFO Using config files '['./DistUpgrade.cfg.trusty']'
2020-02-21 15:40:19,744 INFO uname information: 'Linux dwcube 3.13.0-46-generic #79-Ubuntu SMP Tue Mar 10 20:06:50 UTC 2015 x86_64'
2020-02-21 15:40:20,008 INFO apt version: '1.0.1ubuntu2.11'
2020-02-21 15:40:20,008 INFO python version: '3.4.3 (default, Oct 14 2015, 20:28:29) 
[GCC 4.8.4]'
2020-02-21 15:40:20,010 INFO release-upgrader version '16.04.29' started
2020-02-21 15:40:20,018 INFO locale: 'en_US' 'UTF-8'
2020-02-21 15:40:20,023 INFO screen could not be run
2020-02-21 15:40:20,078 DEBUG Using 'DistUpgradeViewText' view
2020-02-21 15:40:20,124 DEBUG aufsOptionsAndEnvironmentSetup()
2020-02-21 15:40:20,125 DEBUG using '/tmp/upgrade-rw-2rv7c9qq' as aufs_rw_dir
2020-02-21 15:40:20,125 DEBUG using '/tmp/upgrade-chroot-2ivk7dlq' as aufs chroot dir
2020-02-21 15:40:20,126 DEBUG enable dpkg --force-overwrite
2020-02-21 15:40:20,156 DEBUG creating statefile: '/var/log/dist-upgrade/apt-clone_system_state.tar.gz'
2020-02-21 15:40:21,428 DEBUG lsb-release: 'trusty'
2020-02-21 15:40:21,429 DEBUG _pythonSymlinkCheck run
2020-02-21 15:40:21,429 DEBUG openCache()
2020-02-21 15:40:21,430 DEBUG No such plugin directory: ./plugins
2020-02-21 15:40:21,430 DEBUG plugins for condition 'PreCacheOpen' are '[]'
2020-02-21 15:40:21,430 DEBUG plugins for condition 'xenialPreCacheOpen' are '[]'
2020-02-21 15:40:21,430 DEBUG plugins for condition 'from_trustyPreCacheOpen' are '[]'
2020-02-21 15:40:21,430 DEBUG quirks: running PreCacheOpen
2020-02-21 15:40:21,430 DEBUG running Quirks.PreCacheOpen
2020-02-21 15:40:21,901 DEBUG /openCache(), new cache size 70340
2020-02-21 15:40:21,901 DEBUG Have broken pkgs, trying to fix them
2020-02-21 15:40:23,069 ERROR self.prepared() failed
2020-02-21 15:40:23,073 DEBUG enabling apt cron job