Environment
Retain 3.X +
Situation
What SMTP mail server address do I use to send mail to O365?
Resolution
You need to point the SMTP to address for whichever server your MX record is pointing to. If you don't know what your mx record is pointing to, you can do the following.
- From the command line, you can run: nslookup -querytype=mx [emaildomain].com
For example, our domain is gwava.com. I ran this query and received the following results:
root@mx1:~# nslookup -querytype=mx gwava.com
Server: 216.83.130.2
Address: 216.83.130.2#53
Non-authoritative answer:
gwava.com mail exchanger = 15 mx2gcs.gwava.com.
gwava.com mail exchanger = 15 mx1gcs.gwava.com.
2. You could also use a website like mxtoolbox.com and do an mx lookup for your domain. These are the results I received:
| Pref | Hostname | IP Address | TTL | |
|---|---|---|---|---|
| 15 | mx1gcs.gwava.com | 69.160.74.93 | 24 hrs | Blacklist Check SMTP Test |
| 15 | mx2gcs.gwava.com | 69.160.74.94 | 24 hrs | Blacklist Check SMTP Test |
You would list either mx1gcs.gwava.com or mx2gcs.gwava.com.
Additional Information
This article was originally published in the GWAVA knowledgebase as article ID 2878.