Antbleed - bad experience with Bitmain Antminer S9

Recently one of my bitcoin miners stopped mining. And then another one.
They were running, making usual noise but spinning down and back up every 5 minutes or so.
I have 4 miners active at that location. So I tried to switch power supplies.
As I was doing that the third stopped mining too. And then the fourth as well.
They were all electrically working and the green light was coming on and off reporting that everything is OK.
Just my mining pool reported that no mining is actually going on.
When I reset it to factory defaults it started mining with predefined pools and credentials.
As soon as I entered my credentials it didn't mine anymore.

I Googled for a solution and found the page
It appears that Bitmain left the back door in the firmware so that they can instruct any miner not to mine anymore.
Hey! I paid for this hardware. I own it! It is mine! What right do you have to do this?

What needs to be done is the following:
Reset your S9 to factory defaults, just in case. Connect to it via SSH. I use Putty
edit the file /etc/hosts
and add the line
Using vi editor is not common knowledge these days so you need to type in
exactly as follows after you connect to S9 via SSH and login as root.

vi /etc/hosts(enter)

Upon reboot enter your pool and credentials and everything should work fine.