Problems getting new Discourse install to work with Rackspace email

I have just installed Docker Discourse on a CentOS 7 server - no issue at all getting it configured and started. However when I attempt to register the admin account, although I get the message “We’ve re-sent the activation email to” on the page, the email is not sent. I am using Rackspace SMTP via the details outlined on their site (had to remove link on account of posting restrictions for new users)

I get the error:
Job exception: Net::ReadTimeout
in /var/www/discourse/log/production.log on the container

This looks like it is a low level connection timeout - I have confirmed that the container has connectivity to Rackspace via the following curl command (had to remove curl command on account of posting restrictions for new users)

This results in the mail being correctly sent and received so the container has connectivity.

I am using the following SMTP configuration in app.yml (had to remove SMTP configuration on account of posting restrictions for new users):

These parameters seem to be correctly replicated to /var/www/discourse/config/discourse.conf on the container following a ‘launcher rebuild app’

Any idea what I am doing wrong with the configuration? Do I need to add any config for TLS?

Any help greatefully received :slight_smile:

Apologies for the lack of information in this post but I kept getting the error “Sorry new users can’t post more than 2 links” despite there only being 1 link in the original post - I had to remove all the config information to get it to post

#DISCOURSE_SMTP_ENABLE_START_TLS: true # (optional, default true)