Cent OS vs Fedora Core 6 for dedicated server

Legal ramifications prevent them from flat out saying it, but CentOS is RH Linux. Fedora is merely RH's free version, unsupported. CentOS should be quite familiar to you. More here ... [webmasterworld.com...]

Will continue on the other thread. Thank you.

// I was searching for "Cent OS" instead of "CentOs" that is why I didnt find related topics. My bad.

Oops, that other topic is too old to reply.

Are there any RAM usage differences?
Could the new CentOS server use more RAM than my current Fedora server? (If I move my content).
I am asking because I now have two fedora versions on two servers, one always uses ~20% RAM and one always ~90% RAM.

CentOS and Fedora are from the same Linux distribution family so you won't see any difference in application paths, etc. Personally I have switched all my servers from Fedora to CentOS and never had a real problem porting shell scripts applications etc.

The large difference is that Fedora tries to add drivers for all kind of new hardware and newer versions of applications as soon as they become available. The applications in CentOS are more stable and mature, but less hardware is supported. But that is generally not an issue for a server. Fedora has one problem and that is the support cycle. Once a new version comes (they are now planning release 13), the old versions are only supported for a period of some months. After that bug and security fixes are only released for the newest version. Therefore you have to upgrade every several months, just to keep your server up to date with the latest security updates. There haven't been any security fixes for your current FC6 for a long time. The support cycle lifetime of CentOS is about the same length as the hardware life cycle. The current CentOS 5 version will receive general updates until 2014 and security fixes until 2017.

The large part of RAM usage is not caused by the OS. The bare operating system will use 150 MB or less, depending on the modules installed. You can often stop daemons which are loaded by default but not needed in a web server environment, like Bluetooth daemons, the cups printer driver, the avahi daemons etc. Applications use the same RAM on CentOS and Fedora, if they are the same version and use the same settings. RAM usage of a web server will be mainly caused by the httpd daemon and MySQL. CentOS uses httpd version 2.2 and MySQL version 5.0. Fedora 6 also uses httpd 2.2 and MySQL 5.0, so RAM usage of these applications shouldn't differ much between Fedora and CentOS. Also porting of your sites from Fedora to CentOS should be relatively easy because of the same application versions.

Thanks all, I will make the switch.