frr_exporter

Free Range Routing (FRR) Exporter

Prometheus exporter for FRR version 3.0+ that collects metrics from the FRR Unix sockets and exposes them via HTTP, ready for collecting by Prometheus.

Getting Started

To run FRR Exporter:

./frr_exporter [flags]

To view metrics on the default port (9342) and path (/metrics):

http://device:9342/metrics

To view available flags:

usage: frr_exporter [<flags>]

Flags:
  -h, --[no-]help                Show context-sensitive help (also try --help-long and --help-man).
      --[no-]collector.bgp.peer-types
                                 Enable the frr_bgp_peer_types_up metric (default: disabled).
      --collector.bgp.peer-types.keys=type ...
                                 Select the keys from the JSON formatted BGP peer description of which the values will be used with the
                                 frr_bgp_peer_types_up metric. Supports multiple values (default: type).
      --[no-]collector.bgp.peer-descriptions
                                 Add the value of the desc key from the JSON formatted BGP peer description as a label to peer metrics. (default:
                                 disabled).
      --[no-]collector.bgp.peer-hostnames
                                 Add the value of the hostname key from the JSON formatted BGP peer description as a label to peer metrics.
                                 (default: disabled).
      --[no-]collector.bgp.peer-descriptions.plain-text
                                 Use the full text field of the BGP peer description instead of the value of the JSON formatted desc key (default:
                                 disabled).
      --[no-]collector.bgp.advertised-prefixes
                                 Enables the frr_exporter_bgp_prefixes_advertised_count_total metric which exports the number of advertised prefixes
                                 to a BGP peer. This is an option for older versions of FRR that don't have PfxSent field (default: disabled).
      --frr.socket.dir-path="/var/run/frr"
                                 Path of of the localstatedir containing each daemon's Unix socket.
      --frr.socket.timeout=20s   Timeout when connecting to the FRR daemon Unix sockets
      --[no-]frr.vtysh           Use vtysh to query FRR instead of each daemon's Unix socket (default: disabled, recommended: disabled).
      --frr.vtysh.path="/usr/bin/vtysh"
                                 Path of vtysh.
      --frr.vtysh.timeout=20s    The timeout when running vtysh commands (default: 20s).
      --[no-]frr.vtysh.sudo      Enable sudo when executing vtysh commands.
      --frr.vtysh.options=""     Additional options passed to vtysh.
      --collector.ospf.instances=""
                                 Comma-separated list of instance IDs if using multiple OSPF instances
      --[no-]collector.bfd       Enable the bfd collector (default: enabled, to disable use --no-collector.bfd).
      --[no-]collector.bgp       Enable the bgp collector (default: enabled, to disable use --no-collector.bgp).
      --[no-]collector.bgp6      Enable the bgp6 collector (default: disabled).
      --[no-]collector.bgpl2vpn  Enable the bgpl2vpn collector (default: disabled).
      --[no-]collector.ospf      Enable the ospf collector (default: enabled, to disable use --no-collector.ospf).
      --[no-]collector.pim       Enable the pim collector (default: disabled).
      --[no-]collector.vrrp      Enable the vrrp collector (default: disabled).
      --web.telemetry-path="/metrics"
                                 Path under which to expose metrics.
      --web.listen-address=:9342 ...
                                 Addresses on which to expose metrics and web interface. Repeatable for multiple addresses.
      --web.config.file=""       [EXPERIMENTAL] Path to configuration file that can enable TLS or authentication.
      --log.level=info           Only log messages with the given severity or above. One of: [debug, info, warn, error]
      --log.format=logfmt        Output format of log messages. One of: [logfmt, json]
      --[no-]version             Show application version.

Promethues configuraiton:

scrape_configs:
  - job_name: frr
    static_configs:
      - targets:
        - device1:9342
        - device2:9342
    relabel_configs:
      - source_labels: [__address__]
        regex: "(.*):\d+"
        target: instance

Docker

A Docker container is available at:

• Docker Hub: tynany/frr_exporter
• GitHub Container Registry: ghcr.io/tynany/frr_exporter

Example

Mount the FRR socket directory (default /var/run/frr) inside the container, passing that directory to FRR Exporter via the --frr.socket.dir-path flag:

docker run --restart unless-stopped -d -p 9342:9342 -v /var/run/frr:/frr_sockets tynany/frr_exporter "--frr.socket.dir-path=/frr_sockets"

If using the --frr.vtysh flag (not recommended)

Mount the FRR config directory (default /etc/frr) and FRR socket directory (default /var/run/frr) inside the container, passing those directories to vtysh options --vty_socket & --config_dir via the FRR Exporter flag --frr.vtysh.options if using:

docker run --restart unless-stopped -d -p 9342:9342 -v /etc/frr:/frr_config -v /var/run/frr:/frr_sockets tynany/frr_exporter "--frr.vtysh --frr.vtysh.options=--vty_socket=/frr_sockets --config_dir=/frr_config"

Collectors

To disable a default collector, use the --no-collector.$name flag, or --collector.$name to enable it.

Enabled by Default

Disabled by Default

Sending commands to FRR

By default, FRR Exporter sends commands to FRR via the Unix sockets exposed by each FRR daemon (e.g. bgpd, ospfd, etc), usually located in /var/run/frr. If the sockets are located in a folder other than /var/run/frr, pass that directory to FRR Exporter via the --frr.socket.dir-path flag.

VTYSH

If desired, FRR Exporter can interface with FRR via the vtysh command by passing the --frr.vtysh flag to FRR Exporter. This is not recommended, and is far slower than FRR Exporter's default way of sending commands to FRR via Unix sockets. The default timeout is 20s but can be modified via the --frr.vtysh.timeout flag.

BGP: Peer Description Labels

The description of a BGP peer can be added as a label to all peer metrics by passing the --collector.bgp.peer-descriptions flag. The peer description must be JSON formatted with a desc field. Example configuration:

router bgp 64512
 neighbor 192.168.0.1 remote-as 64513
 neighbor 192.168.0.1 description {"desc":"important peer"}

If an unstructured description is preferred, additionally to --collector.bgp.peer-descriptions pass the --collector.bgp.peer-descriptions.plain-text flag. Example configuration:

router bgp 64512
 neighbor 192.168.0.1 remote-as 64513
 neighbor 192.168.0.1 description important peer

Note, it is recommended to leave this feature disabled as peer descriptions can easily change, resulting in a new time series.

BGP: Advertised Prefixes to a Peer

This is an option for older versions of FRR. If your FRR shows the "PfxSnt" field for Peers in the Established state in the output of show bgp summary json, you don't need to enable this option.

The number of prefixes advertised to a BGP peer can be enabled (i.e. the frr_exporter_bgp_prefixes_advertised_count_total metric) by passing the --collector.bgp.advertised-prefixes flag. Please note, older FRR versions do not expose a summary of prefixes advertised to BGP peers, so each peer needs to be queried individually. For example, if 20 BGP peers are configured, 20 'sh ip bgp neigh X.X.X.X advertised-routes json' commands are sent to the Unix socket (or vtysh if the --frr.vtysh is used). This can be slow, especially if using the --frr.vtysh flag. The commands are run in parallel by FRR Exporter, but FRR executes them in serial. Due to the potential negative performance implications of running vtysh for every BGP peer, this metric is disabled by default.

BGP: frr_bgp_peer_types_up

FRR Exporter exposes a special metric, frr_bgp_peer_types_up, that can be used in scenarios where you want to create Prometheus queries that report on the number of types of BGP peers that are currently established, such as for Alertmanager. To implement this metric, a JSON formatted description must be configured on your BGP group. FRR Exporter will then use the value from the keys specific by the --collector.bgp.peer-types.keys flag (the default is type), and aggregates all BGP peers that are currently established and configured with that type.

For example, if you want to know how many BGP peers are currently established that provide internet, you'd set the description of all BGP groups that provide internet to {"type":"internet"} and query Prometheus with frr_bgp_peer_types_up{type="internet"}). Going further, if you want to create an alert when the number of established BGP peers that provide internet is 1 or less, you'd use sum(frr_bgp_peer_types_up{type="internet"}) <= 1.

To enable frr_bgp_peer_types_up, use the --collector.bgp.peer-types flag.

OSPF: Multiple Instance Support

OSPF Mulit-instace is supported by passing a comma-separated list of instances ID to FRR Exporter via the --collector.ospf.instances flag.

For example, if /etc/frr/daemons contains the below configuration, FRR Exporter should be run as: ./frr_exporter --collector.ospf.instances=1,5,6.

...
ospfd=yes
ospfd_instances=1,5,6
...

Note: FRR Exporter does not support multi-instance when using vtysh to interface with FRR via the --frr.vtysh flag for the following reasons:

• Invalid JSON is returned when OSPF commands are executed by vtysh. For example,
  show ip ospf vrf all interface json returns the concatenated JSON from each OSPF instance.
• Vtysh does not support vrf and instance in the same commend. For example,
  show ip ospf 1 vrf all interface json is an invalid command.

Development

Building

go get github.com/tynany/frr_exporter
cd ${GOPATH}/src/github.com/prometheus/frr_exporter
go build

This project uses https://golangci-lint.run in GitHub Actions. You can lint your code locally before submitting a PR by following the installation instructions at https://golangci-lint.run/usage/install/ and run prior to submitting changes:

golangci-lint run 

TODO

• Collector and main tests
• OSPF6
• ISIS
• Additional BGP SAFI
• Feel free to submit a new feature request