How to use the command bmon (with examples)

The bmon command is used to monitor bandwidth and capture network-related statistics. It provides real-time information about data transfer rates, network interfaces, and more.

Use case 1: Display the list of all the interfaces

Code:

bmon -a

Motivation: This use case allows you to view a list of all the network interfaces available on your system. It can be helpful when troubleshooting network connectivity issues or when you need to specify a specific interface for monitoring.

Explanation: The -a option is used to display all the available network interfaces.

Example output:

Interface          Received          Sent              Total
------------------ ----------------- ----------------- --------
eth0               10KB              20KB              30KB
eth1               5KB               15KB              20KB
lo                 2KB               2KB               4KB

Use case 2: Display data transfer rates in bits per second

Code:

bmon -b

Motivation: Monitoring data transfer rates in bits per second allows you to get a more granular view of network traffic. This can be useful in situations where you need to identify and troubleshoot potential bottlenecks or high traffic usage.

Explanation: The -b option is used to display the data transfer rates in bits per second.

Example output:

Interface          Received          Sent              Total
------------------ ----------------- ----------------- --------
eth0               100Mbps           200Mbps           300Mbps
eth1               50Mbps            150Mbps           200Mbps
lo                 20Mbps            20Mbps            40Mbps

Use case 3: Set policy to define which network interface(s) is/are displayed

Code:

bmon -p interface_1,interface_2,interface_3

Motivation: Setting a policy to define which network interface(s) are displayed allows you to customize the monitoring output based on your specific needs. You can choose to monitor only the interfaces that are relevant to your current task or troubleshoot.

Explanation: The -p option is used to set a policy for displaying specific network interfaces. You need to provide a comma-separated list of interface names as arguments.

Example output:

Interface          Received          Sent              Total
------------------ ----------------- ----------------- --------
eth0               10KB              20KB              30KB
eth1               5KB               15KB              20KB

Use case 4: Set interval (in seconds) in which rate per counter is calculated

Code:

bmon -R 2.0

Motivation: Setting the interval for rate per counter calculation allows you to control the frequency at which the data transfer rates are updated. This can be useful when you need to monitor network traffic in near-real-time or when you want to reduce the amount of network bandwidth used by the monitoring tool.

Explanation: The -R option is used to set the interval (in seconds) for rate per counter calculation. In the example, the interval is set to 2.0 seconds.

Example output:

Interface          Received          Sent              Total
------------------ ----------------- ----------------- --------
eth0               100Mbps           200Mbps           300Mbps
eth1               50Mbps            150Mbps           200Mbps
lo                 20Mbps            20Mbps            40Mbps

Conclusion:

The bmon command is a versatile tool for monitoring network bandwidth and capturing network-related statistics. By using the various options and arguments, you can customize the output to suit your specific monitoring needs. Whether you need to view a list of interfaces, monitor data transfer rates, define a specific policy, or set the update interval, bmon has got you covered.