Recently I had to configure my VPS at Slicehost.com to send out emails for my TubeCaption application. Due to the time constraint of the launch, we decided to outsource the mail delivery to Gmail SMTP server.
Using Gmail SMTP server with ActionMailer
When I first deployed the application, I didn’t configure sendmail correctly (I’m a total stranger to sendmail or postfix) and went ahead with Google’s SMPT server. Since I am using Google Apps to host the mailboxes, I created an extra account specifically to use for mail delivery. In my development.rb and production.rb file, I have ActionMailer configured as follow:
ActionMailer::Base.delivery_method = :smtp
ActionMailer::Base.smtp_settings = {
:tls => true,
:address => “smtp.gmail.com”,
:port => 587,
:domain => “tubecaption.com”,
:authentication => :plain,
:user_name => “sample-mailer-account@tubecaption.com”,
:password => “the-very-secured-password”
}
Within my ActionMailer handler, I have a function to setup the default params as follow
class Postoffice < ActionMailer::Base
def setup_default_params
@from = “my-email@tubecaption.com”
@headers = “Reply-to my-email@tubecaption.com”
@subject = “TubeCaption.com”
@sent_on = Time.now
@content_type = “text/html”
end
end
Then for each email, before sending, I invoke setup_default_params() to have all the params setup. The site could now sending out emails, albeit slow. ActionMailer had to open a connection to GMail, authenticated, and then started writing the content as a stream of text. The whole process took from 1 to 3, or even 4 seconds some time on my machines, which means the mongrel process was also stuck there waiting. But the mailing piece worked. However, I came to know the real issue: all the emails were marked as SPAM or JUNK if they are sent to GMail or Yahoo.
I talked to a friend of mine, who has more knowledge in the emailing world. He suggested the cause of this is because emails sent from my VPS failed the reversed DNS lookup verification. Yahoo mail servers perform a reverse DNS look up to check my domain’s DNS records, while the SMTP server I used was from Gmail. Hence the emails were marked as spam in Yahoo and junk in Gmail due to the DNS check mis-match.
So I decided that it was about time for me to configure sendmail for the box and switch ActionMailer to use sendmail instead.
ActionMailer with local sendmail
Truthfully speaking, I would love to get away as far as I can from configuring sendmail. The 4th edition O’Reilly book on Sendmail is more than 1,000 pages! I only want something that can send out emails… Luckily, there is yum.
# sudo yum install sendmail
Now I switch my ActionMailer config back to use sendmail. Since my sendmail is installed in the default folder, I don’t need to configure ActionMailer any further. In production.rb, I have
ActionMailer::Base.delivery_method = :sendmail
ActionMailer now delivered mails using the local sendmail program.
Using the console, I sent out a test email to my yahoo acount. Everything works. Then, I received a notice from my server, telling me I have new mails at /var/spool/mail. Great! I checked the mail log, and saw …
—– The following addresses had permanent fatal errors —–
<nworld3d@yahoo.com>
(reason: 553 Mail from XX.XXX.XXX.XXX not allowed - 5.7.1 [BL23] Connections not accepted from IP addresses on Spamhaus XBL; see http://postmaster.yahoo.com/550-bl23.html [550])
—– Transcript of session follows —–
… while talking to b.mx.mail.yahoo.com.:
<<< 553 Mail from XX.XXX.XXX.XXX not allowed - 5.7.1 [BL23] Connections not accepted from IP addresses on Spamhaus XBL; see http://postmaster.yahoo.com/550-bl23.html [550]
… while talking to d.mx.mail.yahoo.com.:
<<< 553 Mail from XX.XXX.XXX.XXXnot allowed - 5.7.1 [BL23] Connections not accepted from IP addresses on Spamhaus XBL; see http://postmaster.yahoo.com/550-bl23.html [550]
…….
<<< 553 Mail from XX.XXX.XXX.XXX not allowed - 5.7.1 [BL23] Connections not accepted from IP addresses on Spamhaus XBL; see http://postmaster.yahoo.com/550-bl23.html [550]
554 5.0.0 Service unavailable
…….
Final-Recipient: RFC822; nworld3d@yahoo.com
Action: failed
Status: 5.5.0
Diagnostic-Code: SMTP; 553 Mail from XX.XXX.XXX.XXX not allowed - 5.7.1 [BL23] Connections not accepted from IP addresses on Spamhaus XBL; see http://postmaster.yahoo.com/550-bl23.html [550]
Last-Attempt-Date: Tue, 3 Jun 2008 14:02:54 -0400
OUCH! My VPS got black-listed! Somehow the Spamhaus XBL list decided to black list the IP address of the server. Probably because I had port 25 opened in the firewall and somebody has taken advantage of my lack-of-linux-sysadmin-skills to start relaying spams. CRAP! Yahoo outrightly refused any SMTP connection from my server because it was marked as a spammer-wannabe . Good thing Yahoo included the link to their help page and references to Spamhaus XBL.
I went to Spamhaus website and looked up my server’s IP:
The CBL (composite blocking list) was blocking my server. I went ahead and request a removal from the list. Afterwards, the CBL list showed
A few minutes later, I checked Spamhaus and it’s not showing the IP listed anymore. Phew!
It would take a while before this list is propagated through out the internet. At the moment, I still can’t connect to Yahoo’s SMTP server and my mails is still delivered right into Google’s Junk mailbox. Hopefully a few hours more and my server would be good to go.
I don’t know if Spamhaus is my friend or foe. I have a hard time deciding it. I don’t know what people’s experiences with emailing services in general, but I can tell it’s a pain in the butt, and everything will only get worse from here. I wonder what it will be like when ipv6 is used…
