Debian 9 support and repository format issue for Imunify360.list

Issue

While repository URL can be checked:

https://repo.imunify360.cloudlinux.com/imunify360/debian/9/dists/stretch/main/binary-amd64/

For some reason Debian 9 while using Imunify360 repository URL may return incorrect format for the repository in the component part. This format issue prevents Imunify360 to be installed on a Debian 9 systems and apt update returns errors:

E: Wrongly specified entry 1 in list file /etc/apt/sources.list.d/imunify360.list (Component)
E: Could not read font lists.

Also upon attempting to install packages from this repository, the repository string in /etc/apt/sources.list.d/imunify360.list was found to revert to its incorrect format.

Environment

• Debian 9
• Plesk
• Imunify360 6.12 and above

Solution

Although the correct repository format can be established as follows:

echo 'deb [arch=amd64] https://repo.imunify360.cloudlinux.com/imunify360/debian/9 stretch main' > /etc/apt/sources.list.d/imunify360.list

Debian 9 is no longer supported since version 6.12, and there will no future releases for this platform as per:

• Debian 9 (up to Imunify v6.11 (including)), 10, and 11 (Plesk, DirectAdmin, and standalone)

More on prerequisites is in documentation:
https://docs.imunify360.com/installation/#requirements
 

As such, despite binaries seemingly able to run on Debian 9 and it was possible to download the packages after fixing the URL the proper work of the product is not guaranteed and the best course of action would be to upgrade your system to a supported version of Debian or another supported Linux distribution.

Cause

Seemingly there is an issue in how URL parsing, nonetheless Debian 9 is not supported - since 6.12 version of the product. And there will be no new releases for this platform.

Useful links

https://docs.imunify360.com/installation/#requirements