GitLab SSL certificate error

Modify the letsencrypt rb file to disable the staging cert section

sudo vi /opt/gitlab/embedded/cookbooks/cache/cookbooks/letsencrypt/resources/certificate.rb

comment out the following block

acme_certificate 'staging' do
    alt_names new_resource.alt_names unless new_resource.alt_names.empty?
    key_size new_resource.key_size unless new_resource.key_size.nil?
    group unless
    owner new_resource.owner unless new_resource.owner.nil?
    chain "#{new_resource.chain}-staging" unless new_resource.chain.nil?
    contact contact_info
    crt "#{new_resource.crt}-staging"
    key "#{new_resource.key}-staging"
    dir new_resource.acme_staging_endpoint
    wwwroot new_resource.wwwroot
    sensitive true

PRO TIP: use ctl + v to enter visual mode. then press j to move the cursor down the column. press shift+i to enter insert mode. press # to comment out the first line. press esc to commit a # for the entire visual select column.

If all else fails. disable SSL and reconfigure to get the server back online

Note: Its helpful to have a FQDN as the hostname of the machine

 sudo hostnamectl set-hostname --static