We have EDP members will do some testing job in my system , but sometimes these process will generate some error to the system log or any file ( usually the members don't know the log is reached to this level ) , then make the system crashed , could suggest the way how can to prevent this problem ? eg. restrict the file size . thx

Any file? Explain please.

As far as system logs - you can control what gets logged normally with the syslog config file. Since you didn't put what your OS and version is, I can only guess that it's /etc/syslog.conf. This may or may not work in your situation since you put the statement 'generate some error to the system log or any file' which doesn't make sense (at least to me).

You should allow processes to crash your system by allowing log files to be in a partition that could crash the server. Move your log files to a partiton where it will hang the process, not the server. Again, without knowing more information, that is all I can suggest.

Have you looked into disk quotas or if this is a core file, restricting building of core files (setting up core to a link to /dev/null will make it to users can't cause a core file to fill up their home directory, which in turn won't fill up / if that is how your server is set up.

Give more info on the file that is being made - post your OS and version - look into disk quota, syslog.conf, and/or link core to /dev/null.

Also look at the ulimit command. It can limit the size of any file.