Wireless Troubleshooting Tools

Installation

Requirements

The only requirement to run the setup is to have docker and docker-compose installed

Setup

On the Cisco C9800 wireless controller, configure telemetry data:

Code Snippet
Copytelemetry ietf subscription 0
 encoding encode-kvgpb
 filter xpath /wireless-client-oper:client-oper-data/traffic-stats
 source-address 9.9.71.50
 stream yang-push
 update-policy periodic 1000
 receiver ip address 9.9.71.130 57500 protocol grpc-tcp

Then, enable restconf

Code Snippet
Code Snippet - 1
Copyip ssh version 2
aaa new-model
aaa authorization exec default local
username cisco privilege 15 password 0 cisco
restconf
ip http secure-server

Copywireless profile policy my_policy
 no shutdown

wireless tag policy my_tag1
wlan franssid policy my_policy

ap 00a6.ca6c.d590
policy-tag my_tag1

ap f44e.0543.3454
policy-tag my_tag1

Once Docker and Docker-compose are installed, just bring up docker-compose:

Code Snippet
Copydocker-compose up -d

The first the command is executed, the container for pipeline will be built, which will take some minutes. Eventually all 3 containers should come up:

Code Snippet
CopySuccessfully tagged grafana_pipeline:latest
WARNING: Image for service pipeline was built because it did not already exist. To rebuild this image you must use `docker-compose build` or `docker-compose up --build`.
Starting grafana_influx_1   ... done
Starting grafana_grafana_1  ... done
Creating grafana_pipeline_1 ... done

Verification

To verify all 3 containers are up, you can use docker-compose ps to show the current status:

Code Snippet
CopyFSEDANOC-M-C1Z8:grafana fsedanoc$ docker-compose ps
       Name                     Command               State                       Ports
------------------------------------------------------------------------------------------------------------
grafana_grafana_1    /run.sh                          Up      0.0.0.0:3000->3000/tcp
grafana_influx_1     /entrypoint.sh influxd           Up      0.0.0.0:2003->2003/tcp, 0.0.0.0:8086->8086/tcp
grafana_pipeline_1   /bin/bash -c /pipeline/bin ...   Up      0.0.0.0:57500->57500/tcp

Accessing each container

To access each of the container, from the main repository path, use docker-compose exec <container_name> bash, where <container-name> is either grafana, influx or pipeline

Real time logging of raw data

Pipeline is configured to dump the raw data from the controller to the file /data/dump.txt, and the data after filtering to /running_data/metricsdump.txt*. Please note this configuration is not appropiate for a production environment, since the raw data files will grow quickly. Data dump can be disabled by changing pipeline configuration, as described on the following section.

Updating pipeline configuration

The entire pipeline, including it's config file is in the pipeline container, which is built first time docker-compose is brought up, or when docker-compose build is executed.

To change pipeline configuration, from your repository, edit the file pipeline/pipeline_data/pipeline.conf_REWRITTEN

Once that file is update, stop and rebuild the pipeline container with

Code Snippet
Copydocker-compose stop pipeline
docker-compose up -d --build pipeline

Pipeline filters

When pipeline receives gRPC data it runs it thru a filter, which is described via the JSON file /data/metrics.json. This file needs to match the data being received from the wireless controller.

On this example, we'll be plotting client stats (traffic, RSSI). The JSON filter needs to match the YANG data model, and is as follows:

Code Snippet
Copy[
   {
       "basepath" : "Cisco-IOS-XE-wireless-access-point-oper:access-point-oper-data/radio-oper-data",
       "spec" : {
           "fields" : [
               {"name" : "radio-slot-id", "tag" : true},
               {"name" : "radio-type"},
               {"name" : "admin-state", "track" : true},
               {"name" : "wtp-mac", "tag" : true},
               {"name" : "phy-ht-cfg", 
                   "fields" : [
                       {"name" : "cfg-data", 
                           "fields" : [
                               {"name" : "chan-width"},
                               {"name" : "curr-freq"}
                           ]
                       }
                   ]
               }
           ]
       }
   },
  {
          "basepath" : "Cisco-IOS-XE-wireless-access-point-oper:access-point-oper-data/ethernet-if-stats",
          "spec" : {
                  "fields" : [
                          {"name" : "admin-state"},
                          {"name" : "if-name", "tag" : true},
                          {"name" : "rx-total-bytes"}
                  ]
          }
  },
  {
              "basepath" : "Cisco-IOS-XE-wireless-client-oper:client-oper-data/traffic-stats",
              "spec" : {
                      "fields" : [
                              {"name" : "ms-mac-address", "tag": true},
                              {"name": "bytes-rx"},
                               {"name": "bytes-tx"},
                               {"name": "data-retries"},
                               {"name": "mic-mismatch"},
                               {"name": "mic-missing"},
                               {"name": "most-recent-rssi"},
                               {"name": "most-recent-snr"},
                               {"name": "pkts-rx"},
                               {"name": "pkts-tx"}
                      ]
              }
      }
]

Creating graph

Once the containers are brought up, Grafana web interface can be accessed via port 3000 on the instance public IP.

Use admin / admin as the initial user and password.

Datasource definition

Setup a data source as shown on the following capture, the important parameters are:

  • Type: influxdb
  • URL: http://influx:8086
  • Access: Server
  • Database: vwlcdata

Data source configuration

Graph definition

Once datasource is setup, you can define graphs using the interactive builder. An example can be found below:

Graph definition

This is the resulting graph output:

Client RSSI Graph

Changing controller config data from Dashboard

It's also possible to change the controller configuration programatically from the dashboard. The buttons on this example dashboard will trigger a config change to the controller via RESTconf

Buttons

Config change architecture

Config change is implemented using several buttons on the dashboard, which when pressed will cause the browser to send a POST request to a custom application. The flow can be seen here

RESTConf

The custom application listens for any of the following requests from the browser:

  • /start_ap1
  • /start_ap2
  • /stop_ap1
  • /stop_ap2

This application runs on a separate container and, when any of this REST calls is received, will do several operations towards the controller using RESTConf:

  • Get current AP configuration (RESTConf GET)

This is the URL sent to retrieve the current config

Code Snippet
CopyGET /restconf/data/Cisco-IOS-XE-wireless-ap-cfg:ap-cfg-data/ap-tags/ap-tag/

The reply we're getting is as follows:

Code Snippet
Copy{
  "Cisco-IOS-XE-wireless-ap-cfg:ap-tag": [
    {
      "ap-mac": "00:a6:ca:6c:d5:90",
      "policy-tag": "tag2"
    },
    {
      "ap-mac": "f4:4e:05:43:34:54",
      "policy-tag": "my_tag1"
    }
  ]
}

  • Update config in memory

  • Update the config on controller (RESTConf PATCH)

Code Snippet
CopyPATCH /restconf/data/Cisco-IOS-XE-wireless-ap-cfg:ap-cfg-data/ap-tags/ap-tag/
{
 "Cisco-IOS-XE-wireless-ap-cfg:ap-tag": [
   {
     "ap-mac": "00:a6:ca:6c:d5:90",
     "policy-tag": "other-policy-tag"
   },
   {
     "ap-mac": "f4:4e:05:43:34:54",
     "policy-tag": "my_tag1"
   }
 ]
}

At this point, controller config is updated.

Next