Immediate exit due to unhandled exception

My mongo server closes automatically after running for few minutes after I start it.

Any helps?

Can you please provide the entire log (using paste bin for example) along with the actions you are doing right before the error happens?
Also, can you share the configuration of this cluster and how you are starting the node(s)?
Do you also have enough RAM / disk space in this system?

Also, are you running on a supported platform? Which one?