Well it seems this wasn't the issue (Although a 700MB log file after only one day is an issue by itself) causing the crashes, as the same thing happened earlier today. No warnings, errors, information or anything, the server just stops. Any idea what could be causing that or where I could find more info? I've ran a tekkit server on this server for several months and this is the first time I've had this problem.
The server has 2x Dual Core 3GHz processors, 15K RPM SAS Drives, and tekkit has 3GBs of ram dedicated to it; there isn't much else running on the machine atm either. I have WorldGuard, WorldEdit, WorldBorder, Dynmap, Multiverse, Essentials, PermissionsBukkit, and ChopTree plugins installed.
Thank you for any help.