> > > Hello, > > I have a question about sendmail and mail in general. > > I want to know is it possible to know if there are some specific users in > some specific servers. > for example On mydomain.com I have user myuser@xxxxxxxxxxxx, and > people from > outside want to know if this user exists or not ?, so how can they do that > ?. I mean to know this, without sending email. Otherwise they can send > email, and if the mail does not come back, It means the user exists :). > Or without sending email to him, how can I know, is there a such user > ivantan@xxxxxxxxxxx ?. > Is your question is it possible in general? Or is it possible to set something up that does this? It is possible to some extent to test it. You can telnet to port 25 and ask to verify. I think years ago /usr/lib/sendmail -bv [address] used to work. These days, for security reasons, I don't think it is possible to find out. A lot of email addresses are aliased in various ways, or dropped, or forwarded on (there are also a lot of 'catchall' aliases (meaning anyemailaddress@xxxxxxxxxx is forwarded to one account)) that there is no way verify without sending an email to postmaster him/herself. (And there are quite a few sites that don't even use the postmaster@ address anymore) Ben -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
