Get:10 http://download.zerotier.com/debian/bionic bionic InRelease
Err:10 http://download.zerotier.com/debian/bionic bionic InRelease
Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?)
Reading package lists... Done
E: Failed to fetch http://download.zerotier.com/debian/bionic/dists/bionic/InRelease Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?)
E: The repository 'http://download.zerotier.com/debian/bionic bionic InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
Ubuntu and I guess others too got the problem that if the url is not https it is not working. Any reason why http is used instead of https? https://github.com/zerotier/install.zerotier.com/blob/master/install.sh.in#L177