Don't use @ mentions please. You will need to spend some time reading and interacting with Discourse to be elevated to the trust level that allows mentions that will alert and email other users.
Edit: I checked your post and I see that you had an @127.0.0.1 in your dig command, since the command output was not wrapped in a code fence block, Discourse assumed you were trying to mention a user. I've added in your output and formatted that output to be viewed as code instead of just a text paste.