remove
ifconfig-pool-persist ipp.txt
no, there is no way to use static ips for multiple machines while using only certificate auth, and every client having the same certificates.
your setup thinks every client is the same client!
you
SHOULD go make more certificates, and setup your VPN correctly.
the only time production vpn should use duplicate-cn is when you also use password auth.
if you choose to add login/password auth to your setup, then use --username-as-common-name to set the common-name to be the username, instead of the one from the certificate.
