In this guide, we’ll walk you through the process of creating alerts in Log Server 2024R2 so you can monitor your systems more effectively.

1. Log into Nagios Log Server

Start by logging into Nagios Log Server using the credentials you created during the installation process.

2. Create New Alert

Once logged in, navigate to the left-hand menu and click the bell icon to access the Alerting section. Here, you can view any previously created alerts. To create a new alert, click on “New Alert.” A configuration window will appear.

3. Fill in the following to define your alert

Alert Name

• Choose a name that accurately describes the purpose of your alert (e.g., “Failed SSH Login.”)

Type

• Query: Ideal for checking historical log data within a specified time period.
• Real-Time: Monitors logs as they are ingested, providing immediate detection.
• Host Freshness: Tracks if a host is actively sending logs, useful for detecting system outages.

In this example, we’ll use the Query type and leave the next option as undefined.

Check Interval

• This determines how often the system checks the query. You can specify intervals in seconds (s), minutes (m), hours (h), or days (d).

Example: 1m to check every minute.

Lookback Period

• Defines how far back the system will look when executing the query.

Example: 15m to examine the last 15 minutes of logs.

Warning Threshold

• The number of matching events that trigger a warning notification.

Critical Threshold

• The number of events that escalate the alert to critical status.

In this scenario, we’ll set the warning threshold to 2 and the critical threshold to 3. This is especially useful for identifying brute-force login attempts before they escalate into larger issues.

Nagios Log Server offers several notification options:

• Nagios (send using NRDP.)
• Execute Script.
• Send an SNMP Trap.
• Email Users.
  

You can configure multiple alerts and customize how notifications are delivered—or even trigger automated scripts in response to alerts. For example, you could automatically shut down a machine if a certain condition is met.

4. Select the Take Ownership Option

You’ll also see an option to “Take Ownership”. Selecting this checkbox ensures that only users with admin rights can modify or delete the alert.

5. Create Alert

Once all settings are configured, click “Create Alert”. If you choose the Query type, you can find your alert under the Query section.

6. Final Steps

Click the three-dot menu next to your alert to access the following options:

• Show alert in Dashboard.
• Run this alert now.
• Deactivate this alert.
• Edit this alert.
• Remove.

That’s it! You’ve successfully created an alert in Log Server 2024R2. Alerts are a powerful feature that can significantly improve your ability to respond to system issues in real time. If you prefer a visual guide, we recommend checking out our YouTube tutorial, which walks through this entire setup step-by-step.

Introduction

Setting up email alerts in Nagios XI is essential for proactive monitoring of critical systems. When a server, application, or network device experiences an issue, Nagios XI can send email notifications to alert administrators in real time. This ensures IT teams respond quickly to failures, minimizing downtime, and improving system reliability.

This guide will walk you through configuring email alerts in Nagios XI, covering SMTP settings, user notifications, and troubleshooting tips.

1. Configuring Mail Settings in Nagios XI

Before setting up alerts, Nagios XI must be configured to send emails via SMTP (Simple Mail Transfer Protocol).

A. Access Mail Settings

• Log in to Nagios XI
• Navigate to Admin > System Config > Mail Settings

B. Choose Mail Transfer Method

Under the Mail Settings tab, choose one of the following methods:

• Sendmail (default, for local mail relay)
• SMTP Server (recommended for external email providers like Gmail, Office 365, or custom SMTP servers)

C. Configure SMTP Settings (Recommended)

1. Set the SMTP server (e.g., smtp.gmail.com for Gmail, smtp.office365.com for Outlook)
2. Enable authentication if required
3. Enter SMTP credentials (username and password for authentication)
4. Set the sender email address (e.g., nagios@yourdomain.com)
5. Save changes and test email delivery by sending a test message

2. Configuring User Notifications

Once email settings are configured, you need to enable notifications for users to receive alerts.

A. Enable Email Notifications for a User

1. Go to Admin > Manage Users
2. Select the user who should receive alerts
3. Click the Notification Preferences tab
4. Enable Email Notifications
5. Choose the types of alerts the user should receive:
   • Host Down/Recovery Alerts
   • Service Failure Alerts
   • Acknowledged Problems
6. Save changes

3. Configuring Notification Settings for Hosts and Services

To ensure email alerts are triggered when a system issue occurs, hosts and services must have notification settings enabled.

A. Enable Notifications for Hosts

1. Navigate to Configure > Core Config Manager
2. Go to Hosts > Select a Host
3. Click the Alert Settings tab
4. Ensure Notifications Enabled is set to On
5. Select Notification Contacts (users to receive alerts)
6. Click Apply Configuration to save changes

B. Enable Notifications for Services

1. Navigate to Configure > Core Config Manager > Services
2. Select a monitored service (e.g., CPU Load, Disk Space)
3. Go to the Alert Settings tab
4. Enable notifications and set a contact group
5. Save and apply the configuration

4. Testing Email Alerts in Nagios XI

Once notifications are set up, test the alert system:

1. Trigger a failure: Manually stop a monitored service (e.g., Apache) to generate an alert: sudo systemctl stop httpd
2. Check if Nagios XI sends an email notification when the service goes down
3. Restart the service and verify that a recovery alert is sent: sudo systemctl start httpd

5. Troubleshooting Email Notification Issues

If emails are not being sent, try the following fixes:

A. Check Nagios XI Mail Logs

Run the following command to check mail logs for errors:

tail -f /var/log/maillog

Look for SMTP authentication failures or connection issues.

B. Verify Firewall and Port Settings

Ensure outbound SMTP traffic is not blocked:

sudo firewall-cmd --add-port=587/tcp --permanent
sudo firewall-cmd --reload


(Replace 587 with 465 or 25 based on your SMTP provider).

C. Check Email Sending Permissions

Ensure Nagios XI has permission to send emails by testing with:

echo "Test Email" | mail -s "Nagios Test" user@example.com

If this fails, review SMTP credentials and authentication settings.

Conclusion

Setting up email alerts in Nagios XI is crucial for real-time monitoring and quick incident response. By configuring SMTP settings, enabling notifications for users, and testing alerts, IT teams can ensure they receive critical alerts when servers, applications, or network devices fail. Regular testing and troubleshooting will keep your alert system running smoothly.

Learn more about Nagios XI by visiting our Nagios XI Resource page.

Why Use Discord Webhooks with Nagios XI?

• Real-Time Alerts: Get instant notifications about system events.
• Centralized Monitoring: Team members can monitor alerts from a single Discord channel.
• Easy Setup: The Discord Notification Wizard in Nagios XI simplifies the configuration.
• Customizable Notifications: Configure alerts for specific hosts, services, or severity levels.

Step 1: Create a Discord Webhook

To receive alerts in Discord, you first need to generate a webhook URL.

1. Open Discord and Navigate to Server Settings
   • Open Discord and go to the server where you want to receive Nagios XI notifications.
   • Click on the server name at the top left and select “Server Settings”.

2. Create a Webhook
   • In the left sidebar, go to “Integrations”.
   • Under Webhooks, click “Create Webhook”.

Give your webhook a name and choose the channel where alerts will be posted.

Click “Copy Webhook URL”—it will look something like this:

https://discord.com/api/webhooks/1234567890/abcdefghijklmnopqrstuvwxyz

https://discord.com/api/webhooks/1234567890/abcdefghijklmnopqrstuvwxyz

Step 2: Configure Discord Webhook in Nagios XI

Nagios XI provides a Discord Notifications Wizard to streamline the webhook setup.

Navigate to Run a Wizard

Pick the Discord Notifications wizard

Now, paste the webhook that you copied from discord and select the hosts or services that you want to be notified about.

Click Next, and Next again. Now you can configure your notification settings or click Finish to finish your setup.

Conclusion

By integrating Discord webhooks with Nagios XI, you can ensure that critical alerts reach your team in real time. This enhances your monitoring workflow, reduces response time, and improves overall system reliability. With the Discord Notifications Wizard, setup is straightforward, making it an excellent solution for IT teams looking to optimize alert management.

Access the Slack API

To get started, go to the Slack API website and log in with your Slack account. Click Your Apps and Create New App. Then you will see a popup. Select From Scratch. Now give your app a name and choose a workspace that you want to receive notifications in. Then click Create App.

Navigate to Incoming Webhooks and Activate Incoming Webhooks.

Scroll down to Add New Webhook to Workspace and select it.

Copy the Webhook URL and now open your Nagios XI instance.

Integrating with Nagios XI

Run a Wizard.

Find the Slack Notifications wizard.

Paste the Webhook URL into Nagios XI and pick the Hosts/Services you want to be notified about. Click Next, and then Finish. Congratulations! Now you will receive notifications from Nagios XI in Slack!

Conclusion

By integrating Slack with Nagios XI using the Slack Notifications Wizard, you can automate critical alerts and receive notifications directly in your preferred Slack channels. This setup ensures that you stay informed about system events and can take prompt action when needed. With webhook-based notifications, you can enhance your IT monitoring workflow and improve response times to incidents.

This document is intended for use by Nagios Administrators who wish to integrate Twilio with Nagios XI to receive SMS alerts without using an email setup.

Integrating Twilio SMS with Nagios XI – 2024 & 2026

Integrating Twilio with XI 2026

Integrating Twilio SMS with Nagios XI – v5 (Legacy)

Integrating Twilio with XI 5

This document is intended for use by Nagios Users who want to respond to incidents by email.

Nagios XI Inbound Email Commands – 2024 & 2026

XI 2026 Inbound Email Commands

Nagios XI Inbound Email Commands – v5 (Legacy)

XI 5 Inbound Email Commands

This document is intended for use by Nagios Administrators that want to use Slack for notifications.

NNA 2026

Integrating Slack with NNA 2026

This document is intended for use by Nagios Administrators that want to use Slack for notifications.

Nagios XI 2024 & 2026

Integrating Slack with Nagios XI 2026

Nagios XI v5 (Legacy)

Integrating Slack with Nagios XI 5

Configuring Email Notifications in Nagios XI – 2024 & 2026

Configuring Email Notifications in XI 2026

Configuring Email Notifications in Nagios XI – v5 (Legacy)

Configuring Email Notifications in XI 5