Hi,

I am new to owning the VPS and learning alot of things, i search for for the answers on DO and came across alot of posts some made few sense and some none probably due to my lack of knowledge.

The problem I am having is after moving to DO some of my emails that I send are getting bounced back and the error I get it as following

(reason: 550 Access denied - Invalid HELO name (See RFC2821 4.1.1.1))

After googling some posts suggests I need to look into my configuration to make sure they are done right for example make sure FDQN is setup.

When I run the command hostname i see my hosting listed on terminal so i am assuming that right, when i run the command hostname -f i see the following on terminal

localhost.localdomain

So here is my first question is that right? is localhost.localdomain what we are supposed to be using? if not then how do i fix it and what to i change that to?

inside my host file i see the following lines

127.0.1.1 localhost.localdomain hostname hostname
127.0.0.1 localhost

Is this setup right? what am i missing?

Any help will be really appreciated