Installing Passenger
Enterprise Linux 9: Red Hat, CentOS, Rocky, Alma (with RPM)

Relevant selection for this article:

Step 1: enable EPEL

The instructions differ depending on whether you are on Red Hat or another Enterprise Linux. The second step is only necessary on Red Hat.

$ sudo dnf install -y dnf-utils
$ sudo dnf install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-$(< /etc/redhat-release tr -dc '0-9.'|cut -d \. -f1).noarch.rpm
$ sudo dnf config-manager --enable epel
$ sudo dnf clean all && sudo dnf update -y

$ sudo subscription-manager register --username $RHN_USERNAME --password $RHN_PASSWORD --auto-attach
$ sudo subscription-manager repos --enable rhel-9-server-optional-rpms

Step 2: repair potential system issues

These commands will fix common issues that prevent dnf from installing Passenger

# Ensure curl and nss/openssl are sufficiently up-to-date to talk to the repo
sudo dnf update -y

date
# if the output of date is wrong, please follow these instructions to install ntp
sudo dnf -y install chrony
sudo systemctl enable chronyd
sudo firewall-cmd --permanent --add-service=ntp
sudo firewall-cmd --reload
sudo systemctl restart chronyd

Step 3: install Passenger packages

These commands will install Passenger dynamic Nginx module through Phusion's RPM repository.

If you want to use our packaged Nginx module, you must use your distro's provided Nginx package. If for example you have the repo provided by NGINX setup, you will instead need to compile a dynamic module compatible with that Nginx.

# Install various prerequisites
sudo dnf install -y  curl

# Add our el9 RPM repository
sudo curl --fail -sSLo /etc/yum.repos.d/passenger.repo https://oss-binaries.phusionpassenger.com/yum/definitions/el-passenger.repo

# Install Passenger dynamic Nginx module
sudo dnf module enable -y nginx:$(sudo dnf module list nginx | cut -d ' ' -f 2 | grep -Ee '^[0-9\.]+$' | sort -V | tail -1)
sudo dnf install -y nginx-mod-http-passenger || { sudo dnf config-manager --enable cr && sudo dnf install -y nginx-mod-http-passenger ; }

Step 4: restart Nginx

Now that the Passenger Nginx module is installed, restart Nginx to ensure that Passenger is activated:

$ sudo systemctl restart nginx

Step 5: check installation

After installation, please validate the install by running sudo /usr/bin/passenger-config validate-install. For example:

$ sudo /usr/bin/passenger-config validate-install
 * Checking whether this Phusion Passenger install is in PATH... ✓
 * Checking whether there are no other Phusion Passenger installations... ✓

All checks should pass. If any of the checks do not pass, please follow the suggestions on screen.

Finally, check whether Nginx has started the Passenger core processes. Run sudo /usr/sbin/passenger-memory-stats. You should see Nginx processes as well as Passenger processes. For example:

$ sudo /usr/sbin/passenger-memory-stats
Version: 5.0.8
Date   : 2015-05-28 08:46:20 +0200
...

---------- Nginx processes ----------
PID    PPID   VMSize   Private  Name
-------------------------------------
12443  4814   60.8 MB  0.2 MB   nginx: master process /usr/sbin/nginx
12538  12443  64.9 MB  5.0 MB   nginx: worker process
### Processes: 3
### Total private dirty RSS: 5.56 MB

----- Passenger processes ------
PID    VMSize    Private   Name
--------------------------------
12517  83.2 MB   0.6 MB    PassengerAgent watchdog
12520  266.0 MB  3.4 MB    PassengerAgent server
12531  149.5 MB  1.4 MB    PassengerAgent logger
...

If you do not see any Nginx processes or Passenger processes, then you probably have some kind of installation problem or configuration problem. Please refer to the troubleshooting guide.

Step 6: update regularly

Nginx updates, Passenger updates and system updates are delivered through the dnf/yum package manager regularly. You should run the following command regularly to keep them up to date:

$ sudo dnf update

After an update, you should restart Nginx. Doing so will automatically restart Passenger too.