For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:asemen/openSUSE_Tumbleweed/home:asemen.repo
zypper refresh
zypper install fail2ban
For openSUSE Factory run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:asemen/openSUSE_Factory/home:asemen.repo
zypper refresh
zypper install fail2ban
For SLE 12 SP5 Backports run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:asemen/SLE_12_SP5_Backports/home:asemen.repo
zypper refresh
zypper install fail2ban