Sometimes the behavior exhibited by Postfix just does not match the
source code. Why can a program deviate from the instructions given
by its author? There are two possibilities.
In both cases, the program being executed is not the program
that was supposed to be executed, so anything could happen.
There is a third possibility:
Hardware-related failures usually do not reproduce in exactly
the same way after power cycling and rebooting the system. There's
little Postfix can do about bad hardware. Be sure to use hardware
that at the very least can detect memory errors. Otherwise, Postfix
will just be waiting to be hit by a bit error. Critical systems
deserve real hardware.
When a compiler makes an error, the problem can be reproduced
whenever the resulting program is run. Compiler errors are most
likely to happen in the code optimizer. If a problem is reproducible
across power cycles and system reboots, it can be worthwhile to
rebuild Postfix with optimization disabled, and to see if optimization
makes a difference.
In order to compile Postfix with optimizations turned off:
% make tidy
% make makefiles OPT=
This produces a set of Makefiles that do not request compiler
optimization.
Once the makefiles are set up, build the software:
% make
% su
Password:
# make install
If the problem goes away, then it is time to ask your vendor
for help.
