I'm using my Ubuntu 16.04 LTS with Unity 7.4.5 as a remote server as well as a desktop computer. Unfortunately, when I reboot Ubuntu, I can't get X server benchmarks to run without physically going to my display and logging in directly.
Before I do this physical screen login, I see:
t@t:~$ DISPLAY=:0 glmark2-es2
Invalid MIT-MAGIC-COOKIE-1 key
After I physically login, I see
t@t:~$ DISPLAY=:0 glmark2-es2
=======================================================
glmark2 2014.03+git20150611.fa71af2d
=======================================================
And the program runs successfully.
Is there some command I can run remotely to somehow initialize / setup the X server on :0? A related question (https://unix.stackexchange.com/questions/199891/invalid-mit-magic-cookie-1-key-when-trying-to-run-program-remotely) doesn't seem to solve the problem.
EDIT: I tried running startx -- :500 and then DISPLAY=:500 glmark2-es2 to try to bypass this problem altogether. However, I get
test@test:~$ DISPLAY=:500 glmark2-es2
Error: main: Could not initialize canvas