how to use elgg to large implementation !!!

please help me how to handle very large database and very large content like images, files etc. My website is hosted over single Linux server with 4 GB ram and 40 GM disk space for my site. Now my site is increasing very fast currently my database size grown to 500mb(Approx) and 25 GB hard disk space(Approx).

Now I am not sure how to handle large database. As per my knowledge the best way to handle very large website CDN implementation (Please suggest If CDN is the best way to handle large sites) .


Did anyone tired CDN Implementation on elgg. I am trying to move my data folder to other server (CDN server) changed the path of the data in the Data base my site is not picking the images please help!!! I do not found any document related to CDN implementation with elgg I not sure how people use elgg to large implementation.


 Even I have problem in back up also I am not sure how to take back-of 500 mb DB weekly and 25 GB data from data folder every forth night please help. If I do it manually its take lot of hrs which is not feasible option even I tried with script even its taking lot of time.