I just setup httpd 2.4 on an Amazone AMI and I noticed in the httpd.conf file there are alot of directives missing compared to a 2.2 conf file. For example: ServerTokens, Timeout, Server Signature, LoadModule are all not present.
My question is, if they arent explicitly set in the httpd.conf file are they being set somewhere else? If not, what are their default values and why arent they in the conf file.
Should I manually be setting these directives?
Most directives will have default values. You'll find all of the default values here: http://httpd.apache.org/docs/2.4/mod/directives.html
There's nothing to worry about leaving them blank if they're unused. To remove any ambiguity some people prefer to include the directives with their default values in place.
Also worth noting that there are some changes between 2.2 and 2.4 in terms of default values: http://httpd.apache.org/docs/2.4/upgrading.html
On the systems I manage the ServerTokens/Signature settings are in separate include files in the 'extra/' config directory. There are lines near the bottom of httpd.conf to include these extra files that are commented out by default. I'm sure it's been like that since at least v2.2 though, unless the distribution I use installs a customised set of config files.
As James says the server has default settings for most things and only need to be set if you want to change them.
I found the Amazon AMI includes a line that loads modules from the a directory which is why I couldnt find the LoadModule directive
Include conf.modules.d/*.conf
inside that directory contained the following conf files
00-base.conf 00-dav.conf 00-lua.conf 00-mpm.conf 00-proxy.conf 01-cgi.conf 10-php.conf