When using later OpenSSH versions with IPv6 it appears as if OpenSSH tries to do a CNAME lookup on the address and then warns what the format is incorrect, user1@XXXX[12:18][home/user1/Desktop]$ ssh -V OpenSSH_9.6p1, OpenSSL 3.1.5 30 Jan 2024 user1@XXXX[12:18][home/user1/Desktop]$ /app/moshell/24.0f/moshell/commonjars/ssh.lin64 user@2001:1:8100:a3::fe ignoring bad CNAME "2001:1:8100:a3::fe" for host "2001:1:8100:a3::fe": domain name "2001:1:8100:a3::fe" contains invalid characters ssh: connect to host 2001:1:8100:a3::fe port 22: Connection refused user1@XXXX[12:18][home/user1/Desktop]$ Usernames, hostnames and IP addresses are replaced with other values. It is apparently able to establish a connection with the destination, even though port 22 is not in use. Does anyone know why OpenSSH treats valid IPv6 addresses as CNAMEs and tries to do a DNS lookup on these? Further, would it be possible for me to remove this behavior by configuration? BR Patrik _______________________________________________ openssh-unix-dev mailing list openssh-unix-dev@xxxxxxxxxxx https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev