Deprecating Linux Repositories

The Linux repositories that existed on are deprecated and should no longer be used. The following error will occur when updating the repositories:

$ sudo apt-get update

Certificate verification failed: The certificate is NOT trusted. The certificate chain uses expired certificate.  Could not handshake: Error in the certificate verification. [IP: 443]

To get around this issue, you need to remove any references to Search for in any files in /etc/apt/sources.list.d/ and delete these files. Run the following command:

$ grep /etc/apt/sources.list.d/*
/etc/apt/sources.list.d/pcoip.list:deb      [arch=amd64] bionic stable
username@ABCDEF1:~$ sudo rm /etc/apt/sources.list.d/pcoip.list

Once the legacy file is removed refresh the repository cache. 

$ sudo apt-get update

pcoip.list is an example filename that may be captured with the $ grep command.