# Arista LANZ Consumer Input Plugin

This service plugin consumes messages from the
[Arista Networks’ Latency Analyzer (LANZ)][lanz] by receiving the datastream
on TCP (usually through port 50001) on the switch's management IP.

> [!NOTE]
> You will need to configure LANZ and enable streaming LANZ data, see the
> [documentation][config_lanz] for more details.

⭐ Telegraf v1.14.0
🏷️ network
💻 all

[lanz]: https://www.arista.com/en/um-eos/eos-latency-analyzer-lanz
[config_lanz]: https://www.arista.com/en/um-eos/eos-section-44-3-configuring-lanz

## Service Input <!-- @/docs/includes/service_input.md -->

This plugin is a service input. Normal plugins gather metrics determined by the
interval setting. Service plugins start a service to listen and wait for
metrics or events to occur. Service plugins have two key differences from
normal plugins:

1. The global or plugin specific `interval` setting may not apply
2. The CLI options of `--test`, `--test-wait`, and `--once` may not produce
   output for this plugin

## Global configuration options <!-- @/docs/includes/plugin_config.md -->

Plugins support additional global and plugin configuration settings for tasks
such as modifying metrics, tags, and fields, creating aliases, and configuring
plugin ordering. See [CONFIGURATION.md][CONFIGURATION.md] for more details.

[CONFIGURATION.md]: ../../../docs/CONFIGURATION.md#plugins

## Configuration

```toml @sample.conf
# Read metrics off Arista LANZ, via socket
[[inputs.lanz]]
  ## URL to Arista LANZ endpoint
  servers = [
    "tcp://switch1.int.example.com:50001",
    "tcp://switch2.int.example.com:50001",
  ]
```

## Metrics

For more details on the metrics see the [protocol buffer definition][proto].

- lanz_congestion_record:
  - tags:
    - intf_name
    - switch_id
    - port_id
    - entry_type
    - traffic_class
    - fabric_peer_intf_name
    - source
    - port
  - fields:
    - timestamp        (integer)
    - queue_size       (integer)
    - time_of_max_qlen (integer)
    - tx_latency       (integer)
    - q_drop_count     (integer)

- lanz_global_buffer_usage_record
  - tags:
    - entry_type
    - source
    - port
  - fields:
    - timestamp   (integer)
    - buffer_size (integer)
    - duration    (integer)

[proto]: https://github.com/aristanetworks/goarista/blob/master/lanz/proto/lanz.proto

## Sample Queries

Get the max tx_latency for the last hour for all interfaces on all switches.

```sql
SELECT max("tx_latency") AS "max_tx_latency" FROM "congestion_record" WHERE time > now() - 1h GROUP BY time(10s), "hostname", "intf_name"
```

Get the max tx_latency for the last hour for all interfaces on all switches.

```sql
SELECT max("queue_size") AS "max_queue_size" FROM "congestion_record" WHERE time > now() - 1h GROUP BY time(10s), "hostname", "intf_name"
```

Get the max buffer_size for over the last hour for all switches.

```sql
SELECT max("buffer_size") AS "max_buffer_size" FROM "global_buffer_usage_record" WHERE time > now() - 1h GROUP BY time(10s), "hostname"
```

## Example Output

```text
lanz_global_buffer_usage_record,entry_type=2,host=telegraf.int.example.com,port=50001,source=switch01.int.example.com timestamp=158334105824919i,buffer_size=505i,duration=0i 1583341058300643815
lanz_congestion_record,entry_type=2,host=telegraf.int.example.com,intf_name=Ethernet36,port=50001,port_id=61,source=switch01.int.example.com,switch_id=0,traffic_class=1 time_of_max_qlen=0i,tx_latency=564480i,q_drop_count=0i,timestamp=158334105824919i,queue_size=225i 1583341058300636045
lanz_global_buffer_usage_record,entry_type=2,host=telegraf.int.example.com,port=50001,source=switch01.int.example.com timestamp=158334105824919i,buffer_size=589i,duration=0i 1583341058300457464
lanz_congestion_record,entry_type=1,host=telegraf.int.example.com,intf_name=Ethernet36,port=50001,port_id=61,source=switch01.int.example.com,switch_id=0,traffic_class=1 q_drop_count=0i,timestamp=158334105824919i,queue_size=232i,time_of_max_qlen=0i,tx_latency=584640i 1583341058300450302
```
