Self-signed CA making internal API unreachable

From /var/log/gitlab/gitlab-shell/gitlab-shell.log:
WARN – : Failed to connect to internal API <POST https://localhost/api/v3/internal/allowed>: #<OpenSSL::SSL::SSLError: SSL_connect returned=1 errno=0 state=error: certificate verify failed>

Have set: git config --global http.sslVerify false
Crt and key in /etc/gitlab/ssl/ for my local server.
Using gitlab version 8.3.2 gitlab shell version 2.6.9

For the purpose of testing the functionality of git commands in command line i.e. git push/clone

*Could anyone please give some insights on the issue? Maybe gitlab is checking more certs other than the one mentioned above?

All replies appreciated!