i have an ubuntu 18.04 (upgrade from ubuntu 16.04) it was menber of domain as ubuntu 16.04 (in samba active directory).
After upgrade i can't see this server in my dns. but it's there because i can't add it as a new host. dns error: "the record alredy exists.)
it's take min. 5 minutes to login via ssh to server.
what should i do? what is wrong?
in var/log/auth.log is error entry every 2 min. pam_unix(cron:session): session opened for user root by (uid=0) then after 2 min. pam_unix(cron:session): session closed for user root