Hello, guys!
Have a nice day!
This post explains how to deal with VCN 5X0 when cannot login to OMU portal.
Problem Description
Cannot log in to OMU portal
VCN 540 with version V100R002C30SPC205 , when do any action it gives the same screen.

Problem Analysis
Reset the Password and did not work, still cannot log in.
Restart the omu portal, Get error cannot restart due to cannot create temp file as there is no space left on device.

Solution Description
Found tmp directory is full, to delete the logs enter: rm MU*
After that, we were able to restart all modules and can log in to omu.
