Hello :)

Is it possible to host 500 heavy websites on a single apache installation?

How many resource do i need to have? 16GB of ram? 3 Ghz cpu?

Will it be a problem to "reload" the virtual host conf file? (if i reload it with: apachectl -k graceful)

Best regards,
Lasse

Yes it is possible but I would not count on it being the fastest thing in the world. 100 is probably a good number but it will depend on how much is being downloaded at a time. Your limit for speed is probably going to be the network connection.
As far as reloading the apache file I normally use

service httpd reload

to reload the config without bringing apache down.

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