Halo CE Server down, why?

[A41~CET]

I was just wondering why the server would be down.   I was able to get on it last night after I downloaded  Halo CE.     I raced a race or 2 before I had to go to bed, thinking that I would beable to get on today and check out the maps.  I go to get on and there is no server. 

I am just curious. 
Are there certain times it is on?  If so when, I would really like to race on it,  I think Halo CE is great.  I love the new maps.

[AR~Hazy]

This server is switched over to a main Halo server at times as well.  Thanks!!