Mail/ftp/web servers, on VIRTUAL!! dedicated server. Also resource usage. Centos 5.
 

Hi. First of all, would 4 or 5 websites, 1 ftp server (when downloading by someone or a few persons or one, concretize) and one mail server (not many emails, just to sound official and have a nice, spam-free email for myself). Websites with not that many, but some, later more visitors, quite high amount of images in some posts (a blog) eat much resources? Like CPU is ~1.8Ghz, maybe 1.6, Xeon, Rams are 1GB total. I'm not asking if it can run it, because i am using itfor other servers, i'm asking how much resources it would eat for each server?

Second of all, i could find guides for normal servers, dedicated ones, what about virtual dedicated servers? Please be sure what is a VDS though. So are there any tutorials for that? You cannot control a few things of this thing.

Also, can i use a few domains for those different websites and for the main computer, which wouldn't interract together? For example, you couldn't connect to the computer usign the domains, but you could connect trough the address given by your server provider, to be exat to a game server?

If you need a better explanation, please ask. Thank you for any answers to these questions.

Using Centos 5 and i would like to use the best software for those things available. I'm not very advanced linux user though, but i want the best software available anyway.

Well if I understand our question of Virtual Dedicated server correctly, I believe that is a virtual server running on a hypervisor based virtualization solution (but I imagine it could be host based too) and each server has it's own dedicated OS to it. Your configuration wouldn't handle that with only 1GB of RAM. Now maybe a quad core Xeon with 4GB of RAM running XEN and Linux virtual machines dedicated to single purposes might work. With your limited resources you are best to just run the services directly in the OS running on the bare metal. CentOS is fine and can do all that your like. Resource usage for the servers you want to run should be minimal, but as you get more activity, i.e. visitors to your web pages on that server resource usage will go up. I suggest taking a baseline of current usage with like top and just monitor it. If you keep it to CLI only, or you at least disable GUI from starting up that will conserve some resources and leave more for the servers as well.

Well, i'm hosting some other purpose servers on the same machine. There is a web panel installation as an os, so i wouldn've asked here in the first place if i didn't. So basically yea, i need those few websites on CentOS and about resource usage... Well, my hosting provider said, that the website is almost using no resources at all, but he has many websites on the same computer, so not only website should be measured, but also the program itself. It's mysql, php, perl, html, dns jobs all over it.

So anyway, what you are saying, that, when it would get more users, it would use much much more resources? Are there any formulas for approximate calculations? Like for let's say 2GHZ cpu and 1GB ram... Divide something or something like that...

Also, i've not very much rams free at the moment. Only about 100MB. But i would probably turn off one of these things i'm hosting, so i should have about 400MB free rams, when hosting the website.

MySQL is likely to take up the most RAM, Apache doesn't use much neither does php, html uses like nothing becasue those are only files dns doesn't use much either. They will use more as they become active though. i.e. if you are getting hits like say 2-3 hits a second on your web site apache is going to be a lot more active and consume more resources to server those files out, also the more PHP files that have to be processed before being server up by apache the more resources php will use. With only 100MB free though I wouldn't recommend trying to run all these additional services. you free it up to 400MB then that should be reasonable.

Okay, thanks for the answer.

Now let's get back to other two questions...

Are there any guides for VIRTUAL dedicated servers around the net... And which software for these things is the best, since there are more than one program...