Backtrace appearing in a log file...?

[Alan DeKok]

On Nov 25, 2016, at 8:59 AM, Stefan Winter <stefan.winter at restena.lu> wrote:
> my 3.0.12 server usually sends SQL statements into a buffer file for 
> radsqlrelay pickup.
> 
> This choked today on invalid SQL syntax, and the reason was a bit 
> surprising:

  That's magical.

> I'm a bit stunned by that. It's one thing that FR crashes, but how
> can it be that it writes its backtrace into a logfile file
> descriptor? Something horrible with file handles must have happened
> there. Unfortunately, this server is running for very long without
> issues and I don't think I can reproduce this.

  Turn off the "panic_action" in radiusd.conf.

  But the server is designed so that all of the gdb IO goes to file descriptors 0/1/2, which is normal.  And, the server opens up 0/1/2 to /dev/null when the server starts.

  i.e. the SQL output should never use file descriptors 0/1/2, and gdb should only use file descriptors 0/1/2.

  Ugh.

  Alan DeKok.