OpenStack Dev Server Setup CentOS

Setting up an OpenStack development environment on CentOS Stream 9 lets you contribute to OpenStack projects, test patches, and explore the codebase. This guide walks through installing DevStack on CentOS Stream 9 for OpenStack 2024.2 Dalmatian development.

Why CentOS Stream 9?

CentOS Stream 9 is the upstream for RHEL 9 and is a first-class OpenStack development platform. Many OpenStack CI jobs run on CentOS Stream, making it ideal for testing patches that will run in RHEL-based production environments.

Prerequisites

Step 1: System Preparation

Update the system and install essential tools:

sudo dnf update -y
sudo dnf install -y git vim python3-devel gcc libffi-devel openssl-devel

Disable SELinux (required for DevStack):

sudo setenforce 0
sudo sed -i 's/^SELINUX=enforcing/SELINUX=permissive/' /etc/selinux/config

Disable firewalld (DevStack manages its own iptables rules):

sudo systemctl disable --now firewalld

Step 2: Create the Stack User

sudo useradd -s /bin/bash -d /opt/stack -m stack
sudo chmod +x /opt/stack
echo "stack ALL=(ALL) NOPASSWD: ALL" | sudo tee /etc/sudoers.d/stack
sudo -u stack -i

Step 3: Clone DevStack

git clone https://opendev.org/openstack/devstack -b stable/2024.2
cd devstack

Step 4: Configure local.conf

cat > local.conf <<'EOF'
[[local|localrc]]
ADMIN_PASSWORD=devstack
DATABASE_PASSWORD=devstack
RABBIT_PASSWORD=devstack
SERVICE_PASSWORD=devstack
HOST_IP=10.0.0.10

# Use OVN for networking
Q_AGENT=ovn
Q_ML2_PLUGIN_MECHANISM_DRIVERS=ovn
Q_ML2_TENANT_NETWORK_TYPE=geneve
OVN_L3_CREATE_PUBLIC_NETWORK=true

# Enable services for development
enable_service placement-api
enable_service tempest

# Development settings
RECLONE=False
LOGFILE=/opt/stack/logs/stack.sh.log
LOG_COLOR=True
VERBOSE=True
EOF

Step 5: Run DevStack

./stack.sh

This takes 30–60 minutes on CentOS Stream 9. It installs all dependencies, databases, message queues, and OpenStack services.

Step 6: Verify the Installation

source openrc admin admin
openstack service list
openstack endpoint list
openstack hypervisor list

Setting Up the Development Workflow

Clone an OpenStack Project

OpenStack uses Gerrit for code review. Set up git-review:

sudo dnf install -y python3-pip
pip3 install git-review

cd /opt/stack
git clone https://opendev.org/openstack/nova
cd nova
git review -s  # configure Gerrit remote

Create a Development Branch

git checkout -b my-feature stable/2024.2
# Make changes...
git add .
git commit -m "Add my feature"

Run Unit Tests

# Install tox
pip3 install tox

# Run all unit tests
tox -e py311

# Run a specific test
tox -e py311 -- nova.tests.unit.test_my_feature

# Run style checks
tox -e pep8

Run Integration Tests with Tempest

source openrc admin admin
tempest run --smoke
tempest run --regex tempest.api.compute.servers

Apply and Test a Gerrit Patch

cd /opt/stack/nova
git review -d <change-number>  # download a patch
sudo systemctl restart devstack@n-api  # restart Nova API to pick up changes

Development Tools

Debugging a Service

To attach a debugger to a running service:

# Stop the service
sudo systemctl stop devstack@n-api

# Run manually in foreground with pdb
cd /opt/stack/nova
python3 -m nova.cmd.api

Or use remote-pdb for debugging inside screen sessions:

import remote_pdb; remote_pdb.set_trace('0.0.0.0', 4444)

Connect: telnet localhost 4444

Troubleshooting

Summary

CentOS Stream 9 provides an enterprise-aligned development platform for OpenStack. DevStack gives you a working cloud to develop against, while tox, git-review, and Tempest form the standard OpenStack development workflow.