whats the total number of os in:
q: set up reverse dns for anti spam? i have a vps lamp server using ubuntu with linode.com.  im using postfix as the mta to do mailout.  all my emails, when sent to yahoo, are flagged as spam.
i want to implement reverse dns to see if it will resolve this issue.   can someone recommend me a guide for this purpose?

a: according to the linode documentation, you can configure reverse dns records using linode manager.

a: whoever owns your ip address (your vps host) will have to setup the reverse dns for you (they own the ip). call their tech support - they may provide some tool for this, or they might need to do it manually.
it is a public ip thats yours alone, right?

user
In the text, there are forty-seven "o"s.
assistant