(section 1 of the man pages). On some systems (I believe Solaris for eg) when you close your ssh connection all of the open jobs you have open are sent a HUP signal. Chances are your program is being killed by this signal (many are). Using nohup will cause the HUP to be ignored so your process won't die when you log out. You just run your command as " nohup my_background_job & " instead of as " my_background_job & ". Let us know if that helps solve it.