server3 postfix/trivial-rewrite[15407]: warning: hash:/etc/postfix/relayhost_map lookup error for "user@server3.<mydomain>.com.au" server3 postfix/trivial-rewrite[15407]: warning: sender_dependent_relayhost_maps lookup failure server3 postfix/error[17434]: B62708488F: to=<[email protected]>, relay=none, delay=0.24, delays=0.2/0.02/0/0.02, dsn=4.3.0, status=deferred (address resolver failure) My assumption is that i need to create a relayhost_map in /etc/postfix/ ,however, i am not sure what goes into this file? (actually i am not sure whether i am supposed to create a file, or whether its supposed to happen automatically when i edit the postfix/master.cf)
I have figured out what the problem is...i followed these two tutorials https://sendgrid.com/docs/Integrate/Mail_Servers/postfix.html https://cloud.google.com/compute/docs/tutorials/sending-mail/using-sendgrid Both tutorials do not mention that the following line (if it exists) in /etc/postfix/main.cf must be commented out or deleted, #sender_dependent_relayhost_maps = hash:/etc/postfix/relayhost_map commenting that line out solved my problem immediately. What i now would like to know is what that line i have commented out is supposed to actually do. Will me having removed it cause any other problems?
