When installing Apache via yum on CentOS 7, you might notice something unusual in your process list:

/usr/sbin/httpd -DFOREGROUND

This isn't actually running Apache in foreground mode as the flag might suggest. Let's demystify what's happening.

Modern CentOS/RHEL 7+ systems use systemd, which handles process management differently from traditional init systems. The -DFOREGROUND flag appears because:

# Check the systemd unit file
systemctl cat httpd.service

# You'll see lines like:
ExecStart=/usr/sbin/httpd $OPTIONS -DFOREGROUND

Systemd requires services to remain in the foreground for proper supervision. The process manager handles the "daemonizing" instead of the application itself.

Despite the flag's name:

• Apache won't terminate when you close your shell
• Systemd maintains proper process supervision
• Logs are correctly handled through journald

Check Apache's status with:

systemctl status httpd
# Should show "active (running)"

ps -ef | grep httpd
# Will show parent and worker processes

If you need to modify this (though not recommended):

# Create override directory
sudo mkdir -p /etc/systemd/system/httpd.service.d/

# Create override file
echo "[Service]
ExecStart=
ExecStart=/usr/sbin/httpd $OPTIONS" | sudo tee /etc/systemd/system/httpd.service.d/override.conf

# Reload systemd
sudo systemctl daemon-reload
sudo systemctl restart httpd

However, the default behavior is actually better for systemd integration and logging.

If you're having issues:

# Check for errors
journalctl -u httpd -b

# Verify systemd thinks it's running properly
systemctl is-active httpd

When you see /usr/sbin/httpd -DFOREGROUND in your process list, it means Apache is running in foreground mode rather than as a traditional daemon. This behavior became the default in newer systemd-based Linux distributions (including CentOS 7) where Apache is managed by systemd rather than traditional init scripts.

In traditional setups, Apache would:

/usr/sbin/httpd -k start

This would fork several processes and detach from the terminal. With systemd, the process management is handled differently:

• systemd expects services to remain in foreground
• Logging is handled through journald
• Process supervision is managed by systemd

No - because systemd is the parent process, not your shell. The process will continue running even if you close your terminal session. This is fundamentally different from manually running a process with & or nohup.

To verify how Apache is being launched:

systemctl cat httpd

You'll likely see an ExecStart line containing the -DFOREGROUND directive. This is intentional and correct for systemd-managed services.

While generally not recommended, you might need traditional daemon mode for:

# Only do this if you have specific compatibility needs
sudo systemctl edit httpd

[Service]
ExecStart=
ExecStart=/usr/sbin/httpd -k start

Remember to reload systemd after making changes:

sudo systemctl daemon-reload
sudo systemctl restart httpd

With foreground mode, logs go to journald by default. To check Apache logs:

journalctl -u httpd

If you prefer traditional log files, ensure these directives exist in your httpd.conf:

ErrorLog "logs/error_log"
CustomLog "logs/access_log" combined