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I just configured a mail server and tried sending a mail to my gmail account with a local email I created with my mail servers DNSs. I didn't go well. I use Redhat server and sendmail and the testing was done with evolution mail.

I had the following error :

"RCPT TO<> failed: <>...
  relaying temporarily denied. Cannot resolve PTR for my IP"

How can I solve this?

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I put this together for myself a long time ago, give it a try and see if it still works. In a terminal window, type:

sudo aptitude install postfix libsasl2 ca-certificates mailx
sudo gedit /etc/postfix/

then add/change this in

smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
biff = no
append_dot_mydomain = no
readme_directory = no
relayhost = []:587
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
smtp_sasl_tls_security_options = noanonymous
smtp_tls_note_starttls_offer = yes
tls_random_source = dev:/dev/urandom
smtp_tls_scert_verifydepth = 5
smtp_tls_CAfile = /etc/postfix/cacert.pem
smtp_use_tls = yes
smtpd_tls_ask_ccert = yes
smtpd_tls_req_ccert =no
smtp_tls_enforce_peername = no
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

edit the /etc/postfix/sasl_passwd to setup your username and password:

sudo gedit /etc/postfix/sasl_passwd


Then do:

sudo chmod 400 /etc/postfix/sasl_passwd
sudo postmap /etc/postfix/sasl_passwd
cat /etc/ssl/certs/Thawte_Premium_Server_CA.pem | sudo tee -a /etc/postfix/cacert.pem
sudo /etc/init.d/postfix restart
share|improve this answer
thanks for cleaning that up. I am still trying to figure out all the editing quirks for the answer window. – d4v3y0rk Sep 11 '12 at 15:46

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