When I was submitting a job, I always seem to get my job deferred and stuck. I used the MAUI "checkjob jobid" function and the detailed information will come up something like
RM Failure, rc: 15041, msg: 'Execution server rejected request MSG=cannot send job to mom, state=PRERUN'
The solution is quite simple. The compute nodes that the scheduler threw to have its iptables on and thus the job was blocked. To solve the issue, just turn off the iptables and it works.