I am scared to upgrade Jira 8.0.1

[Kai He]

My experience with previous installation of Jira Server was horrible customer service, very slow response, often issues take 1-2 days to even respond. Now I am facing with task of upgrading 7.13 to 8.01, and I am scared that the nightmare of dealing with jira customer service all over again. So I am willing to pay to NOT dealing with Jira customer service representative. 

Do someone offer service to guarantee success upgrade without interrupt our current customers.

[Nic Brough -Adaptavist-]

I would recommend asking an Atlassian Solution Partner.

I work for one which does this sort of upgrade work all the time, but I try not to advertise too much here.   I'd strongly recommend using https://partnerdirectory.atlassian.com/ to find one that suits you - people will put different values on the languages available, location (ease of visiting) or experience with specific products, so I think it's worth looking for yourself.

[Kai He]

Okay I am F*Cked... I followed the instructions and upgraded to 8.3.1 and now nothing works. Even the sysadmin account can not be log in. 

[Nic Brough -Adaptavist-]

What went wrong?  What errors did you get during upgrade, on-screen and in the logs?  What did you do differently to the docs?