[petsc-users] DIVERGED_FNORM_NAN

[Alexander Lindsay]

Hi all,

I've built a MOOSE application and the problem I'm studying solves great 
using serial LU. However, when I try to solve in parallel using super 
LU, I encounter many DIVERGED_LINE_SEARCH errors using the default bt 
line search. If I switch to line_search=none, then instead of 
DIVERGED_LINE_SEARCH errors I get DIVERGED_FNORM_NAN errors. I do not 
have a lot of debugging experience, but I am slowly gaining more. Is 
there a good way to get more information about what's causing the NAN's? 
I.e. a specific residual or jacobian statement?

This may not even be an appropriate list to post this problem in (could 
be more on the MOOSE side); apologies if that's the case.

Alex