do-release-upgrade from 18.04 to 20.04 failed
Upgraded successfully from 16.04 to 18.04, then followed the tutorial for upgrade from 18.04 to 20.04.
do-release-upgrade fails with “ERROR doUpdate() failed completely”.
Lots of “ERROR IOError/SystemError”, but this one caught my eye:
ERROR IOError/SystemError in cache.update(): 'E:Failed to fetch https://repos.sonar.digitalocean.com/apt/dists/main/main/Contents-amd64.gz File has unexpected size (200 != 135). Mirror sync in progress? [IP: 184.108.40.206 443]
Where to start debugging this problem?
These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.×