Nginx: fixing 'http2 directive is deprecated'

Intro

Lately I’ve rarely checked the version updates on my VPS stacks. Well, when wanted to add some a new vhost to my Nginx, a lengthy validation message appeared with many [warn] outputs when I ran nginx -t. So that’s make me feel attacked what happen with my Nginx 👀.

Just googled and found that since Nginx version 1.25.1 there is Important changes and it mention deprecation of listen ... http2 directive.

Sources:

But, like in the early of this words, personally Im not sure when it was updated 🤷, because I was used stable Nginx packages from nginx upstream (adding via /etc/apt/sources.list.d).

Dig in

Alrite, let’s have fun with shell right now, so just analyze with…

# ls to sort by date
$ ls -alsht /var/log/apt/

# zcat history one by one; why not
$ zcat /var/log/apt/history.log.2.gz | grep nginx
  Upgrade: nginx:amd64 (1.24.0-1~jammy, 1.26.0-1~jammy)...

# ok, lets see the term.log.2.gz and found it!
$ zcat /var/log/apt/term.log.2.gz | grep nginx
  Preparing to unpack .../11-nginx_1.26.0-1~jammy_amd64.deb ...
  Unpacking nginx (1.26.0-1~jammy) over (1.24.0-1~jammy) ...
  Setting up nginx (1.26.0-1~jammy) ...
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:6
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:22
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:53
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:29
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:30
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:3
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:3
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:3
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/sites-enabled/xxxxx:55

So we got that it jumped from versio 1.24.xx to 1.26.xx. It was expected because stable upstream release from Nginx was using even minior version. Can check it here .

Fixing time

To fix it, just swap the directive sections of http2. Here is the comparison.

server {
  listen 443 ssl http2;
  ...
}

server {
  listen 443 ssl;
  http2 on;
  ...
}

That’s all for my quick writing about fixing http2 directive deprecated on Nginx story.

Thank You!.