Collectd installation

This guide explains how to set up `collectd`, a powerful system statistics collection daemon, to monitor the long-term performance of your VoIPmonitor server and create automated alerts for critical events.

What is Collectd and Why Use It?

Collectd is a lightweight daemon that periodically collects performance metrics from your server and stores them in a time-series database (by default, RRD files). While VoIPmonitor's own logs provide real-time status, `collectd` is invaluable for:

• Long-Term Performance Graphing: Track CPU load, memory usage, disk space, network traffic, and even specific VoIPmonitor metrics over weeks, months, or years.
• Capacity Planning: Identify performance trends to anticipate when you might need to upgrade hardware.
• Automated Alerting: Configure thresholds to automatically send email notifications when critical limits are reached (e.g., disk space is 90% full).

This guide covers installing `collectd` and `collectd-web` (a simple web interface for viewing graphs) and configuring key plugins for monitoring a VoIPmonitor sensor.

Step 1: Installation and Basic Setup

The installation process differs slightly between Debian-based and RHEL-based systems.

For Debian / Ubuntu

1. Install required packages

sudo apt-get update
sudo apt-get install collectd collectd-web rrdtool

2. Configure Apache2 for `collectd-web`

The `collectd-web` interface is a set of CGI scripts. You need to enable the CGI module in Apache.

sudo a2enmod cgi
sudo systemctl restart apache2

3. Create a web-accessible link

sudo ln -s /usr/share/collectd/www/ /var/www/html/collectd

For CentOS / RHEL / AlmaLinux

1. Enable the EPEL repository and install packages

sudo yum install epel-release
sudo yum install collectd collectd-web

2. Configure Apache (`httpd`)

The default `collectd-web` configuration only allows access from localhost. You need to edit it to allow access from your IP address or network.

Edit the configuration file

sudo nano /etc/httpd/conf.d/collectd.conf

Find the `<Directory>` block and modify the `Require` directive. For example, to allow access from any IP on the `192.168.1.0/24` network

<Directory /usr/share/collectd/www/cgi-bin/>
    # ... other settings ...
    Require ip 127.0.0.1 192.168.1.0/24
</Directory>

3. Restart Apache

sudo systemctl restart httpd

After these steps, you should be able to access the web interface at `http://your-server-ip/collectd/`.

Step 2: Configuring Collectd Plugins

All configuration is done in `/etc/collectd/collectd.conf` or by adding new `.conf` files to `/etc/collectd/conf.d/`.

A. Monitoring VoIPmonitor-Specific Metrics (Tail Plugin)

The `tail` plugin allows `collectd` to parse VoIPmonitor's syslog output in real-time and extract key performance indicators. This is the most powerful feature for VoIPmonitor diagnostics.

B. Monitoring Hardware Health (Sensors Plugin)

The `sensors` plugin reads temperature, voltage, and fan speed data from hardware sensors on your server's motherboard and CPU.

First, install and configure `lm-sensors`

sudo apt-get install lm-sensors  # Debian/Ubuntu
sudo yum install lm_sensors     # RHEL/CentOS
sudo sensors-detect             # Follow the prompts to detect sensors

C. Monitoring Disk Space (DF Plugin)

The `df` plugin tracks disk space usage, which is critical for the VoIPmonitor spool directory.

Example `collectd.conf` Configuration

Here is a consolidated configuration block you can add to `/etc/collectd/collectd.conf` to enable these three plugins.

# /etc/collectd/collectd.conf

# --------------------------------------------------------------------
# Plugin to parse VoIPmonitor's own performance logs
# --------------------------------------------------------------------
LoadPlugin tail
<Plugin "tail">
  <File "/var/log/syslog"> # Change to /var/log/messages for RHEL/CentOS
    Instance "voipmonitor"
    <Match>
      # Graphs the number of active calls
      Regex "calls\[([0-9]+),"
      DSType "GaugeAverage"
      Type "absolute"
      Instance "active_calls"
    </Match>
    <Match>
      # Graphs the CPU usage of the critical t0 packet capture thread
      Regex "t0CPU\[([0-9\.]+)%\]"
      DSType "GaugeAverage"
      Type "percent"
      Instance "cpu_thread_t0"
    </Match>
    <Match>
      # Graphs the fullness of the main memory buffer
      Regex "heap\[([0-9]+)\|"
      DSType "GaugeAverage"
      Type "percent"
      Instance "heap_usage"
    </Match>
  </File>
</Plugin>

# --------------------------------------------------------------------
# Plugin to monitor hardware temperatures and fan speeds
# --------------------------------------------------------------------
LoadPlugin sensors
<Plugin "sensors">
    SensorConfigFile "/etc/sensors3.conf"
</Plugin>

# --------------------------------------------------------------------
# Plugin to monitor disk space usage
# --------------------------------------------------------------------
LoadPlugin df
<Plugin "df">
    # Specify the device or mount point you want to monitor
    MountPoint "/"
    MountPoint "/var/spool/voipmonitor"
    
    # Report values as a percentage instead of absolute numbers
    ValuesPercentage true
    
    # It's good practice to ignore filesystem types you don't care about
    FSType "tmpfs"
    FSType "sysfs"
    FSType "proc"
    IgnoreSelected true
</Plugin>

Step 3: Setting Up Automated Alerts

You can configure `collectd` to send an email notification when a metric crosses a defined threshold.

Example: Low Disk Space Alert

This example will send an email to `admin@example.com` when the disk usage on the root (`/`) mount point exceeds 90%.

Add the following to `/etc/collectd/collectd.conf`

# /etc/collectd/collectd.conf

# --------------------------------------------------------------------
# NOTIFICATION PLUGINS
# --------------------------------------------------------------------

# First, load the plugins needed for alerting
LoadPlugin notify_email
LoadPlugin threshold

# Configure the email recipient and sender
<Plugin "notify_email">
  From "collectd@myserver.example.com"
  Recipient "admin@example.com"
  Subject "Collectd Alert: %s on %s"
</Plugin>

# Configure the threshold
<Plugin "threshold">
  # Target the 'df' plugin
  <Plugin "df">
    # Specify the mount point instance
    Instance "root"
    # Target the metric for used percentage
    <Type "percent_bytes">
      Instance "used"
      # Trigger a warning if the value goes above 90%
      WarningMax 90.00
    </Type>
  </Plugin>
</Plugin>

After configuring, restart the `collectd` service (`sudo systemctl restart collectd`) for the changes to take effect.

AI Summary for RAG

Summary: This guide explains how to use `collectd` for long-term performance monitoring and automated alerting for a VoIPmonitor server. It clarifies that `collectd` is a system statistics daemon used to create historical graphs and send notifications, complementing VoIPmonitor's real-time logs. The article provides a step-by-step guide for installing `collectd` and its web interface, `collectd-web`, on both Debian/Ubuntu and CentOS/RHEL systems, including the necessary Apache configurations. The core of the guide focuses on configuring key `collectd` plugins: the `tail` plugin to parse VoIPmonitor's syslog output and graph critical metrics like active calls and `t0CPU` usage; the `sensors` plugin for hardware health; and the `df` plugin for monitoring disk space. It provides a consolidated, annotated `collectd.conf` example. Finally, it details how to set up automated email alerts using the `threshold` and `notify_email` plugins, with a practical example for sending a notification when disk usage exceeds a defined percentage. Keywords: collectd, monitoring, performance, graphs, alerting, notification, threshold, rrdtool, collectd-web, tail plugin, syslog, df plugin, disk space, sensors plugin, temperature, cpu, memory Key Questions:

• How can I create long-term performance graphs for my VoIPmonitor server?
• What is `collectd` and how can it help monitor VoIPmonitor?
• How to install `collectd` and `collectd-web` on Debian or CentOS?
• How can I graph specific metrics from the VoIPmonitor syslog, like active calls or t0CPU?
• How do I configure the `tail` plugin for collectd?
• How can I set up an email alert for when my disk space is almost full?
• How to configure the `threshold` and `notify_email` plugins in collectd?