First of all, if gitlab fails to access the page, don't panic. Generally speaking, if there is an error, look at the log. If you don't know how to solve the prompt in the log, you can ask Du Niang.
First check the status of each component of gitlab:

gitlab-ctl status
 
#Will list whether each component has been successfully started, mine is that redis has not started

Then view the logs of specific components:

The format is gitlab-ctl tail redis //redis can be replaced with other component names

. Look carefully at where the error appears in the log. I have Fatal error loading the DB: Permission denied.
The problem of Exiting is generally caused by the incompatibility of the rdb file. All Find it and delete it

find /var/opt/gitlab/ -name "redis" ///var/opt/gitlab/ is the main directory of gitlab, if you don't know where the components are, you can find them
cd /var/opt/gitlab/redis/
rm -rf dump.rdb