Pi (Raspbian) located on a remote mountain top being used to monitor and control some electronic equipment via an Internet connection ... currently using ssmtp to send I'm alive and Alarm emails to a support email address via gmail's smtp servers ... this gmail service stopped working a while back but we were unable to resolve that because we also lost Internet to the Mountain Top ... now that we finally have Internet back, I have spent several days bashing away at some solutions and finally found that I now needed to turn ON a google option called ALLOW LESS SECURE APPLICATIONS. (not sure if the ssmtp process can be updated to meet gmail's NEW standards BUT also concerned that "less secure" means google at some point could close that door completely)
In the process of my bashing, I came across a possible POSTFIX send-only solution which theoretically should bypass the need for gmail altogether ... problem is I don't understand the configuration details specific to do with the following option:
mydestination = $myhostname, example.com, localhost.com, , localhost
The 3 send only options appear to be straight forward
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = loopback-only
but not sure what is needed for the 5 fields after mydestination
I changed example.com to the domain address of the support email address but get an error stating there is an issue with the HELO address (see ERROR below)
Also wonder if the Pi requires having a DNS listed IP/Domain address to allow POSTFIX to work properly? That wouldn't be possible considering the Pi is:
a) behind a firewall
b) the router has a dynamic address (DHCP assigned by ISP)
Thanks in advance for any insight you can provide
POSTFIX ERROR
- Invalid HELO name (See RFC2821 4.1.1.1) (in reply to MAIL FROM command))
mail.log:46:Nov 4 00:58:51 <device name> postfix/smtp[25810]: AA99326DDD: to=<support email address>, relay=<support email domain [IP address]>:25, delay=4.1, delays=3.4/0.05/0.62/0.05, dsn=5.0.0, status=bounced (host<support email domain [IP address]> said: 550 Access denied
In the process of my bashing, I came across a possible POSTFIX send-only solution which theoretically should bypass the need for gmail altogether ... problem is I don't understand the configuration details specific to do with the following option:
mydestination = $myhostname, example.com, localhost.com, , localhost
The 3 send only options appear to be straight forward
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = loopback-only
but not sure what is needed for the 5 fields after mydestination
I changed example.com to the domain address of the support email address but get an error stating there is an issue with the HELO address (see ERROR below)
Also wonder if the Pi requires having a DNS listed IP/Domain address to allow POSTFIX to work properly? That wouldn't be possible considering the Pi is:
a) behind a firewall
b) the router has a dynamic address (DHCP assigned by ISP)
Thanks in advance for any insight you can provide
POSTFIX ERROR
- Invalid HELO name (See RFC2821 4.1.1.1) (in reply to MAIL FROM command))
mail.log:46:Nov 4 00:58:51 <device name> postfix/smtp[25810]: AA99326DDD: to=<support email address>, relay=<support email domain [IP address]>:25, delay=4.1, delays=3.4/0.05/0.62/0.05, dsn=5.0.0, status=bounced (host<support email domain [IP address]> said: 550 Access denied