Error on starting openvpn server via systemctl on CentOS 7: --cert fails with 'server.crt': No such file - centos

Question

I am setting up my own OpenVPN server on VPS with CentOS 7. I'm totally newbie in Linux.
I am using one article for setting up OpenVPN. Right now I'm on step "Start OpenVPN" and have strange problem.
After running systemctl -f start openvpn#server.service I got an error. I checked details with 'journalctl -xe' and found next issue:
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After googling I understood that systemd has setting that include parameter WorkingDirectory. I checked it:
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It's '/etc/openvpn/server'. OK, I moved all required files there:
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Including server.crt, that wasn't mentioned in article at all (I found it in '/etc/openvpn/easy-rsa/easyrsa3/pki/issued/server.crt').
Then I checked conf file and adjusted name of .pem file:
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Everything looked fine, but I still get an error with --cert parameter:
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I checked that there is no additional config file in openvpn catalog:
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I tried to replace cert parameter with putting this cert data into config file, but looks like it work only with client config:
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I don't understand what may be wrong. I checked all possible obvious and non-obvious issues that may lead to this error which I googled, but nothing helps.
What I could miss?

Answer 1

Ok, just now I got an idea and it worked. I incorrectly assumed, that in my case WorkingDirectory caused this issue initially. So I just copied server.crt from /etc/openvpn/server to /etc/openvpn and it started successfully.