Sendmail Masquerade

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Hi All,

I’m usually quite good with sendmail on CentOS 5.8 but I must have missed something here. I’ve not done this before but, I want to set sendmail so that its outgoing mail appears to come from the domain of the network it lives on. Its real hostname is ( the domain bit is substituted for this post) and I want it to send as, that is really valid, but the specific host does not have an A record and other mailservers reject its outgoing mail because does not resolve. But with these settings in it still sends as if I simply type “mail -s test”
into bash.

MASQUERADE_AS(`’)dnl FEATURE(masquerade_envelope)dnl FEATURE(masquerade_entire_domain)dnl MASQUERADE_DOMAIN(

(Yes I have done the m4 bit and restarted sendmail)

If I telnet to sendmail on port 25 and manually send as it has the right “from” address.

So what have I missed?



2 thoughts on - Sendmail Masquerade

  • Are you doing the test that fails as the ‘EXPOSED_USER’ in
    (i.e. root)? That is for intentional exceptions to MASQUERADE_AS so you can tell where system type messages from cron jobs, etc. originate if you send everything to a mail hub.