Discussions sur Akamai Connected Cloud (formerly Linode)

I am running some web applications those are highly coupled with PHP 7.X and I want to use PHP 8.0 with another application I developed recently. So how do I keep both versions of PHP in the same server.

Eventually, I want to upgrade from Ubuntu server 18.04 to 20, but I have not learned a fast and secure way to do this.

I want to migrate to managing an email service myself. I am a FreeBSD administrator using Linode and want to keep using FreeBSD.

Sometimes we install new capabilities as software but is in cases hard to update them, identify them when are obsolete or deprecated, Is there an alternative to "scan" my server for unused/outdated software? (Not talking about the core apps via apt-get)