Recently we had setup a new linode for testing some internal applications (Php, Python, Go and Node JS) based.

While configuring and testing, we found that the email notification feature had stopped working.

On troubleshooting the issue, we found that the outgoing smtp connections on port 587 to any host (We had tried smtp.gmail.com and smtp.office365.com as we have paid accounts on both the services) is blocked.

What is the process for enabling it?

Raised a support ticket, but have not received any acknowledgement or resolution to it. We feel, this community could help.

And reason why it is blocked in the first place (apart from curtailing spam) without any prior notification or consent from the customer?

Is it documented somewhere that we missed to see and what other restrictions linode has on it's servers?

Had we known all these things, we would not have created the account / servers on linode.

Now moving to another provider and setting up the systems again from scratch is a lot of work.

Any new linode account creators, beware of the restrictions on linode servers, limitations on linode servers, issues with linode servers and requesting everyone to be updated about the linode restrictions.