We have a server onto which we plan to install CentOS 6.2. The server will host Asterisk for our office, but is not a webserver.
If we install the minimal installation for CentOS - that is, no GUI for the OS, then that means that Asterisk will also not be able to be interfaced with a GUI such as FreePBX or Elastix.
I found this thread useful in the consideration: Should I use an Asterisk GUI? My thinking is to provide the GUI for folks who may have to succeed me and who do not know Asterisk so well as to manually maintain the configuration files.
Now, I understand that it is better for a server to run without a GUI. But if it is only meant to host Asterisk, then is it still a bad idea to install the GUI?
Generally speaking, the more extraneous software you run results in two problems:
If your application is not memory intensive, or under particular memory pressure for your hardware, you don't really need to worry about (1). If you can completely isolate the environment your server runs in (hint: you probably can't), then you don't need to worry about (2).
Aren't the GUIs of popular applinces like FreePBX and Elastix web-based anyway? Not sure why you think the OS on your server requires a window manager for a web-based user interface. You say it's not a webserver - what does this mean? You're not allowed to / don't want to install a webserver?
This seems like a silly assumption from the start. For one thing, virtually all of the documentation available for asterisk is in the form of config files, someone approaching your setup from no prior knowledge is more likely to find instructions to deal with those very configs, not a GUI tool.
On the other hand; someone who already knows how to use a particular config tool can probably also sort out how to install it.
In general, I'm very reluctant to install anything that might affect the performance of asterisk (or freeswitch, which we've mostly migrated to). unlike most other services, media switches are highly sensitive to disturbances of load, which may be reflected in poor call quality. Except for things that are actively used, we meticulously police the set of start-up services that run on the switch; and offload absolutely everything we possibly can (within practical reason, of course).
I generally do not recommend it. Even more so if you plan on installing telephony hardware. Certain video card / driver combinations can take a not-insignificant amount of time scrolling the video display which will cause some cards to miss their deadlines or increase jitter on RTP streams. I've seen it work, and I've seen it cause problems.