Did a quick check at http://mxtoolbox.com/to see if the smtp server is blacklisted in the hope I could help fix the issue. Results from simply typing blacklist: theIPaddy, assuming the smtp server is on the same server as the bodhilinux.com site.
edit: also here's a similar result that includes a couple of warnings: http://www.dnsstuff....=bodhilinux.com
This caught my eye:
SMTP greeting Malformed greeting or no A records found matching banner text for following servers, and banner is not an address literal.RFC5321 requires one or the other (should not be a CNAME). If this is not set correctly, some mail platforms will reject or delay mail from you, and can cause hard to diagnose issues with deliverability. Mailserver details:
18.104.22.168 | WARNING: The hostname in the SMTP greeting does not match the reverse DNS (PTR) record for your mail server. This probably won't cause any harm, but may be a technical violation ofRFC5321
22.214.171.124 | WARNING: The hostname in the SMTP greeting does not match the reverse DNS (PTR) record for your mail server. This probably won't cause any harm, but may be a technical violation ofRFC5321
and also this result titled "Checks that the mail server accepts mail to postmaster@ipaddress" which is a bit of a red flag if true, because it may mean that the mail server is not accepting mail , not that gmail, yahoomail, outlook etc are blocking mail from this doman, this is not the same as "postmaster@domain" which is working as expected.
Acceptance of address literals Mailserver rejected mail to address literals. Mailservers are technically required by RFC1123 section 5.2.17 to accept mail to domain literals (i.e. IP addresses instead of domains). This ensures backwards compatibility and can help with delivery in certain non-optimal situations, like a DNS server being down/unresponsive.
126.96.36.199 | unexpected response to [RCPT TO: ] | 550 5.1.1 Recipient not found.
188.8.131.52 | unexpected response to [RCPT TO: ] | 550 5.1.1 Recipient not found. @[184.108.40.206]>@[220.127.116.11]>@[18.104.22.168]>@[22.214.171.124]>
result from mxtoolbox:
Checking 126.96.36.199 against 97 known blacklists...
Listed 0 times with 0 timeouts
Extra edit, went back to mx tools and did an smtp lookup on bodhilinux.com and got this result, which makes it look more like an smtp configuration problem, but although I have done limited dev-ops at work, I know jack poo about smtp.
Unable to connect after 15 seconds. Test Result
SMTP Connect Failed To Connect More Info
Connecting to 188.8.131.52
12/9/2016 1:17:09 PM Connection attempt #1 - Unable to connect after 15 seconds. [15.02 sec]
Edit 3: so then I made a free acount at MXtools to get more information and I got this page here (probably just the first paragraph is relevant):
More Information About Smtp Connect
We attempted a connection to your mail server on port 25 but your server did not respond. More than likely there is no email server at this address or you have a misconfigured firewall or spam filtering system.
If the SMTP Connect test is unable to connect to your mail server after 15 seconds we will report it as an error. For optimal email deliverability it is advisable that SMTP connections should not take longer than 15 seconds.
Here are the networks MxToolbox uses for SMTP Tests. Please add these to your firewall to avoid experiencing connection failures or false alerts.
- 184.108.40.206/28 (Netmask: 255.255.255.240)
- 220.127.116.11/27 (Netmask: 255.255.255.224)
- 18.104.22.168, 22.214.171.124, & 126.96.36.199
Additional Information Tarpitting
It is also possible your server is “Tar pitting.” Tar pitting is a technique used by some email servers to slow down spammers. The idea is that legitimate senders will wait longer to establish a connection than spammers will.
Here is a link to a link to the TechNet article with more information about Tarpitting
Our SMTP test cannot detect problems caused by Back Pressure, a system resource monitoring feature of the Microsoft Exchange Transport service. In order to be alerted for back pressure events you would need to add our end-to-end Mailflow Monitor for your server which can detect any type of email interruption and also provide historical performance data.
Here's a link to the TechNet article with more information about back pressure.