How to disable EXPN and VRFY Command

[Baldeo Prasad_1]

Please let me know, How to disable EXPN and VRFY command. These are commands are used by SMTP.

Thanks in advance.

[Chris Wilshaw]

You need to set the following in your /etc/mail/sendmail.cf file;

O PrivacyOptions=novrfy
O PrivacyOptions=noexpn

There should already be a line in the file reading

O PrivacyOptions=authwarnings

in the file

[Baldeo Prasad_1]

Thanks Chris for your quick response.
Yes, There is already a line in sendmail.cf file and I had just added these command in that line.
O PrivacyOptions=authwarnings, restrictqrun, novrfy, noexpn

[T G Manikandan]

After you modify the /etc/mail/sendmail.cf
Restart sendmail
/sbin/init.d/sendmail stop
/sbin/init.d/sendmail start