Okay, this messed my whole system. I lost exim, webmail as well due to mariadb not coming up after a reboot.
I reinstall exim4 via Exim4 will not come up - #4 by sahsanu, but now my mariadb does not come up, webmail does not work, emails not working. 
@sahsanu do you have any script like the same for mariadb and webmail to work?
Webmail and email error:
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