Hi,

Well done - yes, it was indeed the hosts file entry that would have been the issue. Now, your smart relay is working. But what this error indicates is that smtp.zoho.com requires you to log in or otherwise authenticate beofre you can send mail through it.

What this tells us is that smtp.zoho.com isn’t meant to act as a mail relay or smart host, but rather is just a server for customers to send mail through via a mail client. This is different from a server that can act as a smart host. The general idea of an SMTP smart host is that it takes mail from hosts that would otherwise be unable or unwilling to deliver mail straight to their target on the Internet via SMTP, and it deals with passing the e-mails on to their final destinations. This it would seem is not the configured purpose of smtp.zoho.com.

However, all is not lost. Sendmail can be configured to support this situation, by having a file that tells it how to log in to smtp.zoho.com. You will need a valid username and password for the Zoho e-mail service, and you’d also need to be sure that the maintainers of smtp.zoho.com would be happy for their service to be used as a smart relay. But if all of that is fine, then what you need to do is set up a file called /etc/mail/authinfo with the login details.

Now, one thing that worries me here is that your Sendmail setup for whatever reason seems to be largely ignoring your macro, and so unless /etc/mail/authinfo is already set up in your Sendmail configuration (and it very well may be - have a look and see if it’s mentioned in the .cf), then it’s going to be a very unpleasant job to hack this into working shape.

Anyway, the format of /etc/mail/authinfo (which would then need compiled via makemap hash /etc/mail/authinfo < /etc/mail/authinfo in the usual way) is:

Code:

AuthInfo:smtp.zoho.com "U:USERNAME" "P:PASSWORD" "M:PLAIN"

This sets up authentication for smtp.zoho.com, with the specified username and password, and tells it to use plain-text authentication (which may or may not be right - you’d have to know what kind of authentication is supported for the Zoho SMTP service).

In short: without a working Sendmail macro this could be a lot of work to get up and running. A better bet here is to find another host on your network that can actualy be configured to act as a genuine smart relay for your domain, and to just set Sendmail up to use that host as its smart relay rather than this external service.