4543 connect(3, {sa_family=AF_UNIX, sun_path="private/tlsmgr"}, 110) = -1 ENOENT (No such file or directory)
If you cd into /var/spool/postfix and then try again, it will find the tlsmgr socket. Further I cannot test as it seems my ISP blocks outbound 25/tcp, but in any case I'd suggest to show actual failures from the postfix logs, as this posttls-finger tool is flagged as "an unsupported test program" and might have quirks, like the above (which could still be a bug, i.e, not prefixing the socket path with /var/spool/postfix).
stracing posttls-finger:
4543 connect(3, {sa_family=AF_UNIX, sun_path= "private/ tlsmgr" }, 110) = -1 ENOENT (No such file or directory)
If you cd into /var/spool/postfix and then try again, it will find the tlsmgr socket. Further I cannot test as it seems my ISP blocks outbound 25/tcp, but in any case I'd suggest to show actual failures from the postfix logs, as this posttls-finger tool is flagged as "an unsupported test program" and might have quirks, like the above (which could still be a bug, i.e, not prefixing the socket path with /var/spool/ postfix) .