Display and Manage Network Data with OT CLI

View source on GitHub

Thread Network Data contains information about Border Routers and other servers available in the Thread network. Border Routers and devices offering services register their information with the Leader. The Leader collects and structures this information within the Thread Network Data and distributes the information to all devices in the Thread Network.

Border Routers may register prefixes assigned to the Thread network and prefixes that they offer routes for. Services may register any information relevant to the service itself.

Border Router and service information can be stable or temporary. Stable Thread Network Data is distributed to all devices, including Sleepy End Devices (SEDs). Temporary Network Data is distributed to all nodes except SEDs.

Network Data Commands

For a list of netdata commands, type help:

netdata help
help
full
length
maxlength
publish
register
show
steeringdata
unpublish
Done

`full` commands

The full commands report the flag status or resest the flag tracking whether the "net data full" callback has been invoked.

This command requires OPENTHREAD_CONFIG_BORDER_ROUTER_SIGNAL_NETWORK_DATA_FULL.

`length` and `maxlength` commands

The length command gets the current length of Thread Network Data, reported as number of bytes. maxlength commands gets the maximum observed length, or resets the tracked maximum length.

`publish` commands

The Network Data Publisher provides mechanisms to limit the number of similar Service and Prefix (On-Mesh Prefix or External Route) entries in the Thread Network Data by monitoring the network data and managing when to add or remove entries.

The Publisher requires OPENTHREAD_CONFIG_NETDATA_PUBLISHER_ENABLE.

Form network and configure prefix

Generate new network configuration.
```
dataset init new
Done
```

Display the network configuration.

dataset
Active Timestamp: 1
Channel: 13
Channel Mask: 0x07fff800
Ext PAN ID: d63e8e3e495ebbc3
Mesh Local Prefix: fd3d:b50b:f96d:722d::/64
Network Key: dfd34f0f05cad978ec4e32b0413038ff
Network Name: OpenThread-8f28
PAN ID: 0x8f28
PSKc: c23a76e98f1a6483639b1ac1271e2e27
Security Policy: 0, onrcb
Done

Commit the new dataset to the Active Operational Dataset in non-volatile storage.
```
dataset commit active
Done
```
Enable the Thread interface
```
ifconfig up
Done
thread start
Done
```

Display IPv6 addresses assigned to the Thread interface.

ipaddr
fd3d:b50b:f96d:722d:0:ff:fe00:fc00
fd3d:b50b:f96d:722d:0:ff:fe00:dc00
fd3d:b50b:f96d:722d:393c:462d:e8d2:db32
fe80:0:0:0:a40b:197f:593d:ca61
Done

prefix add fd00:dead:beef:cafe::/64 paros med
Done
netdata register
Done

Display Thread Network Data.
```
netdata show
Prefixes:
fd00:dead:beef:cafe::/64 paros med dc00
Routes:
fd49:7770:7fc5:0::/64 s med 4000
Services:
44970 5d c000 s 4000
44970 01 9a04b000000e10 s 4000
Done
```
Prefixes and routes include argument mappings and the RLOC value.

Service records include otServiceConfig values, including mEnterpriseNumber, mServiceData, otServerConfig::mServerData, and s to indicate otServerConfig::mStable. The RLOC is also appended to the end of the record.
Display the current length, in number of bytes, of Partition's Thread Network Data.
```
netdata length
23
Done
```

Display IPv6 addresses assigned to the Thread interface, including the added prefix.

ipaddr
fd00:dead:beef:cafe:4da8:5234:4aa2:4cfa
fd3d:b50b:f96d:722d:0:ff:fe00:fc00
fd3d:b50b:f96d:722d:0:ff:fe00:dc00
fd3d:b50b:f96d:722d:393c:462d:e8d2:db32
fe80:0:0:0:a40b:197f:593d:ca61
Done

Attach to existing network

Only the Network Key is required for a device to attach to a Thread network.

While not required, specifying the channel avoids the need to search across multiple channels, improving both latency and efficiency of the attach process.

After a device successfully attaches to a Thread network, the device retrieves the complete Active Operational Dataset.

Create a partial Active Operational Dataset.

dataset networkkey dfd34f0f05cad978ec4e32b0413038ff
Done
dataset commit active
Done

Enable the Thread interface.
```
ifconfig up
Done
thread start
Done
```

After attaching to the existing network, display Thread Network Data.

netdata show
Prefixes:
fd00:dead:beef:cafe::/64 paros med dc00
Routes:
Services:
Done

Display the current length, in number of bytes, of Partition's Thread Network Data.
```
netdata length
23
Done
```

Display IPv6 addresses assigned to the Thread interface.

ipaddr
fd00:dead:beef:cafe:4da8:5234:4aa2:4cfa
fd3d:b50b:f96d:722d:0:ff:fe00:fc00
fd3d:b50b:f96d:722d:0:ff:fe00:dc00
fd3d:b50b:f96d:722d:393c:462d:e8d2:db32
fe80:0:0:0:a40b:197f:593d:ca61
Done

Debugging & diagnostics

Network Data has a limited size of 254 bytes. If Border Routers keep adding entries (for example, prefixes, routes, or service entries) to Network Data it can get full. When this happens, new requests from a Border Router to add new items will be rejected or ignored by the leader. The leader does not necessarily signal the rejection to the Border Router so the Border Router may not immediately realize that Network Data is getting full. However, there is a method available to detect when Network Data is getting full.

The detection method, implemented on both Border Routers and the leader, uses a callback API mechanism and allows users to be notified when Network Data is full. The callback can be used to take action, such as removing stale prefixes or service entries. The netdata full commands are used for the flag that tracks whether the "net data full" callback has been invoked. These commands can report the flag's status or reset it.

For the typical use cases of Thread, it is unlikely that Network Data will get full, even in the scenario where there are many Border Routers and they are all adding route prefixes.

It is technically possible for Network Data to get full, however this is often due to misconfiguration or an issue on the Border Router. The netdata length and netdata maxlength commands can help debug Network Data full errors. length gets the current length of Network Data, reported as bytes and maxlength gets the maximum observed length and can also reset the tracked maximum length.