Cisco v2.1 CPF - TTN Backend Config Error: "Server side radio config - Illegal field: lorawan_public"

Hi all,

To keep this brief I’ll skip why, but the gateway was updated successfully to the recent firmware (FW) update from Cisco. This is version which comes with the Common Packet Forwarder (CPF).

Utilising the method provided here: Setting up Basic Station protocol on RAK7240 and RAK7249 industrial gateways , I have jury rigged the Cisco gateway to connect to TTN, but it’s encountering an error when it receives the configuration from TTNs backend.

This error has been diagnosed from the CPF (debug mode) logs accessible on the gateway:

I’ll need to investigate this certificate issue after jury rigging it into working:
2020-10-01 04:46:09.240 [AIO:INFO] tc has no key+cert configured - running server auth only

It connects to TTN here:
2020-10-01 04:46:09.259 [TCE:VERB] Connecting to MUXS…
2020-10-01 04:46:09.367 [TCE:VERB] Connected to MUXS.
2020-10-01 04:46:09.367 [AIO:DEBU] ------------------------------
2020-10-01 04:46:09.367 [AIO:DEBU] sending msg…len=139
2020-10-01 04:46:09.367 [AIO:DEBU] [7|WS] > {“msgtype”:“version”,“station”:“2.0.5(cisco/std)”,“firmware”:“2.0.5”,“package”:“2.0.5”,“model”:“cisco”,“protocol”:2,“features”:“rmtsh gps”}
2020-10-01 04:46:09.367 [AIO:DEBU] ------------------------------
2020-10-01 04:46:09.377 [S2E:DEBU] ------------------------------

Receives config from TTN (error occurs in italics):
2020-10-01 04:46:09.377 [S2E:DEBU] receiving msg…len=1149
2020-10-01 04:46:09.377 [S2E:DEBU] {“msgtype”:“router_config”,“NetID”:null,“JoinEui”:null,“regi
2020-10-01 04:46:09.377 [S2E:DEBU] on”:“AU915”,“hwspec”:“sx1301/1”,“freq_range”:[915000000,9280
2020-10-01 04:46:09.377 [S2E:DEBU] 00000],“DRs”:[[12,125,0],[11,125,0],[10,125,0],[9,125,0],[8,
2020-10-01 04:46:09.377 [S2E:DEBU] 125,0],[7,125,0],[8,500,0],[0,0,0],[12,500,0],[11,500,0],[10
2020-10-01 04:46:09.377 [S2E:DEBU] ,500,0],[9,500,0],[8,500,0],[7,500,0],[0,0,0],[0,0,0]],"sx13
2020-10-01 04:46:09.377 [S2E:DEBU] 01_conf":[{“lorawan_public”:true,“clksrc”:1,“antenna_gain”:0
2020-10-01 04:46:09.377 [S2E:DEBU] ,“radio_0”:{“enable”:true,“freq”:917200000,“rssi_offset”:-16
2020-10-01 04:46:09.377 [S2E:DEBU] 6,“tx_enable”:true},“radio_1”:{“enable”:true,“freq”:91790000
2020-10-01 04:46:09.377 [S2E:DEBU] 0,“rssi_offset”:-166,“tx_enable”:false},“chan_multiSF_0”:{"e
2020-10-01 04:46:09.377 [S2E:DEBU] nable":true,“radio”:0,“if”:-400000},“chan_multiSF_1”:{"enabl
2020-10-01 04:46:09.377 [S2E:DEBU] e":true,“radio”:0,“if”:-200000},“chan_multiSF_2”:{“enable”:t
2020-10-01 04:46:09.377 [S2E:DEBU] rue,“radio”:0,“if”:0},“chan_multiSF_3”:{“enable”:true,"radio
2020-10-01 04:46:09.377 [S2E:DEBU] “:0,“if”:200000},“chan_multiSF_4”:{“enable”:true,“radio”:1,”
2020-10-01 04:46:09.377 [S2E:DEBU] if":-300000},“chan_multiSF_5”:{“enable”:true,“radio”:1,“if”:
2020-10-01 04:46:09.377 [S2E:DEBU] -100000},“chan_multiSF_6”:{“enable”:true,“radio”:1,“if”:1000
2020-10-01 04:46:09.377 [S2E:DEBU] 00},“chan_multiSF_7”:{“enable”:true,“radio”:1,“if”:300000},"
2020-10-01 04:46:09.377 [S2E:DEBU] chan_Lora_std":{“enable”:true,“radio”:0,“if”:300000,"bandwid
2020-10-01 04:46:09.377 [S2E:DEBU] th":500000,“spread_factor”:8},“chan_FSK”:{“enable”:false}}],
2020-10-01 04:46:09.377 [S2E:DEBU] “nocca”:true,“nodc”:true,“nodwell”:true,“MuxTime”:1601527569
2020-10-01 04:46:09.377 [S2E:DEBU] .3780406}
2020-10-01 04:46:09.377 [S2E:DEBU] ------------------------------

2020-10-01 04:46:09.378 [RAL:WARN] Ignoring unsupported/unknown field: gps_conf

2020-10-01 04:46:09.378 [JSN:ERRO] @[0].lorawan_public: Server side radio config - Illegal field: lorawan_public

2020-10-01 04:46:09.378 [RAL:ERRO] Parsing of JSON failed - ‘router_config.sx1301_conf’ ignored

Closes connection to TTN and retries:
2020-10-01 04:46:09.378 [any:ERRO] Closing connection to muxs - error in s2e_onMsg
2020-10-01 04:46:09.378 [AIO:DEBU] [7] ws_close reason=1000
2020-10-01 04:46:09.378 [AIO:DEBU] Echoing close - reason=1000
2020-10-01 04:46:09.387 [AIO:DEBU] [7|WS] Server sent close: reason=1000
2020-10-01 04:46:09.387 [AIO:DEBU] [7] WS connection shutdown…
2020-10-01 04:46:09.387 [TCE:VERB] Connection to MUXS closed in state -1
2020-10-01 04:46:09.387 [TCE:INFO] INFOS reconnect backoff 10s (retry 1)

I have further spoken to ‘Meshed’ who operate the router in Australia for TTN regarding this issue and have been advised to contact Cisco (currently awaiting response, I will update when I receive new info) and TTN.

Unfortunately, this error does not appear to be an issue I can rectify on my end. I suspect it’s due to the FW update from Cisco simply being new and some kinks need to be ironed out.

Thank you in advance for any assistance you can provide and the time you have taken so I can bring this to your attention.


Oh, bummer, I just noticed that the filtered output below still includes lorawan_public So the following probably does not help you, still just in case.

Any chance you see a URL like the following?

And if yes, can you change that to include ?filter=ttn like the following?

This trick feature is also used (at least for EU868) by the Kickstarter The Things Gateway, which would otherwise also fail on unknown fields in the JSON result. (That gateway is not using Basic Station.)

And just in case it helps, the Basic Station implementation in the The Things Indoor Gateway (TTIG) seems to happily ignore unknown fields:

1970-01-01 00:00:16.374 [TCE:VERB] Connected to MUXS.
1970-01-01 00:00:16.685 [S2E:WARN] Unknown field in router_config - ignored: bcning (0x1EE5E245)
1970-01-01 00:00:16.689 [S2E:WARN] Unknown field in router_config - ignored: config (0xF7A3E35F)
1970-01-01 00:00:16.693 [S2E:WARN] Unknown field in router_config - ignored: protocol (0xFD309030)
1970-01-01 00:00:16.701 [S2E:WARN] Unknown field in router_config - ignored: regionid (0xE6FFB211)
1970-01-01 00:00:16.713 [S2E:WARN] Unknown field in router_config - ignored: upchannels (0x7FCAA9EB)

Hi, were you able to get this resolved?

@mpodoski Unfortunately, not yet. I’m still in the process of talking to Cisco about it and I will update if it’s ever resolved.

@arjanvanb It’s not possible, unfortunately.

Though to circumvent this issue I rolled back to FW v2.0.32 to utilise Semtech UDP Packet Forwarder with a cobbled together AS923 template from three different sources for use in Australia as Cisco does not provide the templates, nor provide support for it (hence upgrading to the new firmware where CPF is supported).

For the moment it appears to be working and I’m in the process of testing it.

Thanks Nik393, will do the same…

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We are integrating Cisco IXM v2.1.0.2 (CPF 2.0.5) with LNS v3.10.4 and we are facing the same problem.