How to use the command 'birdc' (with examples)

BIRD (the Internet Routing Daemon) is a popular open-source tool used to manage and manipulate routing policies on routers. The birdc command is the remote control tool for BIRD, and it allows operators to retrieve information about routing tables and protocols, as well as change configurations during runtime. This makes it a highly valuable tool for network administrators who need to manage dynamic routing configurations effectively.

Use case 1: Open the remote control console

Code:

birdc

Motivation:

Opening the remote control console is particularly useful when operators need to interact directly with the BIRD daemon in an interactive manner. This console provides an interface to issue commands and get immediate feedback or results, making it ideal for tests or quick adjustments to the router’s configuration.

Explanation:

The command birdc without any additional arguments opens an interactive shell, similar to a command-line interface, that connects to the running BIRD instance. From this console, you can execute various BIRD commands to manage routing configurations.

Example output:

BIRD 2.0.10 ready.
bird> 

Use case 2: Reload the configuration without restarting BIRD

Code:

birdc configure

Motivation:

Reloading the configuration without restarting BIRD is crucial for maintaining high availability in network operations. It allows network administrators to apply new configurations without interrupting the network services by restarting the daemon. This ensures a seamless transition and minimal downtime.

Explanation:

The configure argument instructs BIRD to reload its configuration files. It reads the configuration anew and applies changes on-the-fly, while keeping the current network sessions and routes intact.

Example output:

Reading configuration from /etc/bird/bird.conf
Reconfigured

Use case 3: Show the current status of BIRD

Code:

birdc show status

Motivation:

Displaying the current status of the BIRD daemon is an essential action to quickly ascertain the health and operational state of the routing service. Network administrators may frequently check the status to ensure everything is functioning as expected and troubleshoot any issues proactively.

Explanation:

The show status command retrieves and displays core information about the operational state of BIRD, such as uptime, router ID, and number of routes managed. This provides a high-level overview of the daemon’s status.

Example output:

BIRD 2.0.10
Router ID is 192.168.1.1
Current server time is 2023-10-23 14:52:06
Last reboot on 2023-10-23 09:12:34
Last reconfiguration on 2023-10-23 14:50:21

Use case 4: Show all configured protocols

Code:

birdc show protocols

Motivation:

Understanding which protocols are currently configured is essential for managing a network efficiently. By viewing all configured protocols, network administrators can verify which routing protocols are active and troubleshoot inter-protocol interactions or misconfigurations.

Explanation:

The show protocols command outputs a list of all routing protocols configured in BIRD, including their states and any relevant details like last state transitions or config errors, helping administrators manage protocol-specific operations.

Example output:

Name       Proto    Table      State  Since         Info
device1    Device   ---        up     2023-10-23   
static1    Static   master4    up     2023-10-23
kernel1    Kernel   master4    up     2023-10-23  

Use case 5: Show all details about a protocol

Code:

birdc show protocols upstream1 all

Motivation:

Understanding the intricate details of a specific protocol can help diagnose issues, optimize configurations, or gain better insights into how the protocol is performing. This level of detail is invaluable during debugging sessions or performance evaluation tasks.

Explanation:

With show protocols upstream1 all, the command is specified to show comprehensive information about the protocol named ‘upstream1’. The keyword all broadens the scope to include detailed statistics and parameters related to the protocol’s operation.

Example output:

Name       Proto      Table      State  Since         Info
upstream1  BGP        bgp1       up     2023-10-23
  Preference: 100
  Input filter: ACCEPT
  Output filter: ACCEPT
...

Use case 6: Show all routes that contain a specific AS number

Code:

birdc "show route where bgp_path ~ [4242120045]"

Motivation:

In BGP operations, identifying all routes containing a specific AS number is critical for understanding paths and dependencies within the network. It allows operators to analyze routing decisions influenced by particular autonomous systems efficiently.

Explanation:

This command utilizes a filter expression show route where bgp_path ~ [4242120045] to display all routing entries that have the AS number 4242120045 in their path. It’s filtered by matching the regular expression pattern within the BGP path attribute.

Example output:

10.0.0.0/24     via 192.168.10.1 on eth0 [bgp1 2023-10-23] * (100) [AS-4242120045]
5.5.5.0/24      via 192.168.10.2 on eth1 [bgp2 2023-10-23] *(200) [AS-4242120045]
...

Use case 7: Show all best routes

Code:

birdc show route primary

Motivation:

Viewing all best routes is important for ensuring that the network routing table is optimal and selections are based on defined policies. This aids in verifying that the best possible routes are being utilized for packet delivery.

Explanation:

The command show route primary highlights all routes currently marked as the best candidate for a given destination, also known as primary routes. This implies routes that have won the BGP decision process.

Example output:

192.168.1.0/24  via 10.0.0.1 on eth0 [bgp1 2023-10-23] * (100)
192.168.2.0/24  via 10.0.0.2 on eth1 [bgp2 2023-10-23] * (200)

Use case 8: Show all details of all routes from a given prefix

Code:

birdc show route for fd00:/8 all

Motivation:

This usage is significant for network engineers who need to examine all routing entries that fall under a specific IPv6 prefix. It’s a crucial function when verifying or troubleshooting IPv6 routes and ensures all route details for blocks of addresses are checked.

Explanation:

The show route for fd00:/8 all command is telling BIRD to display not just the routes for the IPv6 prefix fd00:/8, but to provide all detailed information for these routes, including attributes and routing decisions.

Example output:

fd00:1::/64     dev eth0 weight 1 [direct1 2023-10-23] * (100) [fd00::1]
fd00:2::/64     via fe80::1 on eth1 weight 1 [bgp1 2023-10-23] * (200) [AS63452]
...

Conclusion:

The birdc command provides network administrators with a robust toolkit to manage and monitor BIRD routing configurations. Each use case offers a specific function that can help maintain the stability, performance, and reliability of the routing infrastructure effectively. Understanding how to leverage these commands optimally can significantly enhance both routine management and troubleshooting endeavors.