I recently solved a really old case last week in which Maya 2015 SP5 on Linux would not auto-activate, even though you have an internet connection. This week, the issue came up again but in EMEA.
The solution is quite easy, you just need to run this hotfix:
If we didn't do this, we would need to manually activate Maya on Linux using the method below:
1. Run Maya and close the wizard because it can't auto-activate.
2. Go to /tmp folder and look for the MAYA_2015_0_F_USLongCode.xml and email it to Product Support. i.e. Create a case.
3. We generate an activation code based on the xml file.
4. Launch Maya and there is a Browse button to load the activation xml file.