After setting up the vsftp to use PAM as auth. Somehow having the following error appeared in tail -f /var/log/securetail -f /var/log/secure Sep 21 09:47:45 g-server vsftpd: PAM [error: /lib/security/pam_userdb.so: wrong ELF class: ELFCLASS32]Sep 21 09:47:45 g-server vsftpd: PAM [error: /lib/security/pam_userdb.so: wrong ELF class: ELFCLASS32] and resulting user can’t login to ftp service at all. […]

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