On a computer which is behind a proxy (appropriately configured I hope), after upgrading from Ubuntu 18.04 LTS to 20.04 then 22.04:
- updating/upgrading from the official Ubuntu repositories works fine, so I assume there is no issue with the network configuration
- But updating any non official PPAs always give an error, see below.
> sudo apt update
Ign:1 https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu jammy InRelease
Ign:2 https://download.owncloud.com/desktop/ownCloud/stable/latest/linux/Ubuntu_22.04 InRelease
Hit:3 http://archive.ubuntu.com/ubuntu jammy InRelease
Hit:4 http://archive.ubuntu.com/ubuntu jammy-updates InRelease
Get:5 http://archive.ubuntu.com/ubuntu jammy-backports InRelease [109 kB]
Hit:6 http://archive.ubuntu.com/ubuntu jammy-security InRelease
Hit:7 http://dl.google.com/linux/chrome/deb stable InRelease
Ign:1 https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu jammy InRelease
Ign:2 https://download.owncloud.com/desktop/ownCloud/stable/latest/linux/Ubuntu_22.04 InRelease
Ign:1 https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu jammy InRelease
Ign:2 https://download.owncloud.com/desktop/ownCloud/stable/latest/linux/Ubuntu_22.04 InRelease
Err:1 https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu jammy InRelease
Could not handshake: An unexpected TLS packet was received. [IP: 134.226.56.7 8080]
Err:2 https://download.owncloud.com/desktop/ownCloud/stable/latest/linux/Ubuntu_22.04 InRelease
Could not handshake: An unexpected TLS packet was received. [IP: 134.226.56.7 8080]
Fetched 109 kB in 7s (15.3 kB/s)
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
3 packages can be upgraded. Run 'apt list --upgradable' to see them.
W: Failed to fetch https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu/dists/jammy/InRelease Could not handshake: An unexpected TLS packet was received. [IP: 134.226.56.7 8080]
W: Failed to fetch https://download.owncloud.com/desktop/ownCloud/stable/latest/linux/Ubuntu_22.04/InRelease Could not handshake: An unexpected TLS packet was received. [IP: 134.226.56.7 8080]
W: Some index files failed to download. They have been ignored, or old ones used instead.
It looks like a network error, right? If so why does it happen only with non-official PPAs? Any suggestion how to solve this?