Copy ca.crt and crl.pem to /etc/openvpn with...
sudo cp ca.crt /etc/openvpn
- then press [enter]
sudo cp crl.pem /etc/openvpn
- then press [enter]
Confirmed they are there with...
ls /etc/openvpn/ -altr
- then press [enter]
You should see within the results something like...
-rw-r--r-- 1 root root 1395 Date/Time ca.crt
-rw-r--r-- 1 root root 577 Date/Time crl.pem
https://www.privateinternetaccess.com/forum/discussion/18003/openvpn-step-by-step-setups-for-various-debian-based-linux-oss-with-videos-ubuntu-mint-debian