yubiserver 0.6-3build1 (s390x binary) in ubuntu bionic

 Simple and lightweight Yubikey OTP and HOTP/OATH validation server
 to be used with Yubico's Yubikey USB tokens including a powerful
 administration tool, yubiserver-admin, with which you can manage
 yubiserver's database by adding,deleting,activating and deactivating
 users that validate with OTP or HOTP/OATH tokens.
 .
 Yubiserver implements Yubico's server side API and can be used
 with Yubikey USB tokens and any other client that can implement
 the same API.