Hi ,

I have a strange situation here. I have sendmail on linux. I am using
The Feature(accept unresolved domains) in .mc file.
But when an email is sent from an unresolved domain , sendmail takes a long pause to give 250 OK command after the Mail From command.

Please tell me why this is happening.

Thanks in advance.

to know if the domain is unresolvable, sendmail has to try to resolve it, but DNS responds with some delay; how long does it take for you?

Thank you for the reply.

Its taking a pause long enough that the other server is forced to timedout before 250 OK is sent. may be 30 secs or more.
And strange thing is when i executed dig axfr domainname @dns server on the server itself it is no longer giving a pause. Has it been cached ?
If yes then why it did not use the cache second time when we tried to send the email, we did wait for the 250OK command from the server so it should have resolved for the next tries.

And i tried with some FQDN's which does not exist but sendmail did not take a pause for these. :-(