Sendmail not working on CentOS

Posted on 2009-07-16
Last Modified: 2013-12-18
I have a CentOS server configured with sendmail and none of my messages seem to be sent.

I am looking at the maillog fiel and see this error "Jul 16 13:38:43 fmsubbnix sendmail[1140]: n6GHcgRE001026: n6GHchRE001140: DSN: Host unknown (Name server: host not found)"

My guess is the the parameter "Name server:" is incorrectly configured.   I probably need to use the company's smtp relay server.  Where is this value located?

Question by:gordonmann
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LVL 29

Accepted Solution

fosiul01 earned 500 total points
ID: 24871757
can this server resolv external host ?

smart host , option would be on


look for smart host options in their , and use company smtp server

define(`SMART_HOST', `smtp.your.provider')dnl

dont forget to run


then restart sendmail

Author Comment

ID: 24872056
Please define "dont forget to run make"

LVL 29

Expert Comment

ID: 24872075
if you change any sendmail configuration

you need to execute make command

just type


then restart  sendmail

Author Closing Comment

ID: 31604343
Great -- Thanks

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