These errors are fatal errors, which can impact service for multiple subscribers.

Examples of the error messages:

• Node discovery of SBA fails after query from NRF and local configuration

• Mandatory IE missing in an NGAP message

• Memory cache startup errors

• Endpoint not found

Sample log:

[ERROR] [ApplicationContext.go:1820] [infra.dpd.core] Ping Unsuccessful for client Id 4 Name: amf-protocol-ep0 Setname: amf-protocol-ep Host: amf-protocol-ep Port: 9003 Url:  for [246]

These errors impact few specific call-flows majorly, but not blockers of functionality.

Example of the warning messages:

• Node discovery of SBA fails but we have more options to retry.

• Mandatory IE missing in a NAS message

• RPC timeout

• Procedural timeout

• Validation failure (not critical)

  Example: Registration rejected as Registration request message received registration type as the Reserved registration type.

• External entity sending unexpected or negative response

  Example: Handover Cancel, Hand over Failure, or Initial Context Setup Failure

• Unexpected value of objects maintained by AMF

  Example: NIL value of transaction

• Unable to fetch a subscriber

Sample log:

[WARN] [amf-service.amf-app.messageprocessor] No procedure defined for message type 763

This log level purpose is to know information for cause.

Examples of the information messages:

• Procedural outcome Example: Disabling of ICSR for Registration

• Collision abort, cleanup, suspend, or continue.

Sample log:

[INFO] [amf-service.amf-app.auth] Sending N12 Authentication Request to Rest EP

This log level purpose is to get debug messages.

Example of the debug messages:

• All external exchanged messages

• Sending Registration accept to UE

• State machine changes

• Collision detailed logging

Sample log:

[DEBUG] [process.go:1606] [amf-service.amf-app.reg] [supi:123456789012345] [supi:123456789012345] [1] Preparing registration accept to UE 123456789012345

This log level purpose is to get content of all external tracing messages.

Example of the trace messages:

• Registration request message

• N1N2 transfer message

Sample log:

[TRACE] [process.go:1627] [amf-service.amf-app.reg] [supi:123456789012345] [supi:123456789012345] 
[496] Sending RegistrationAccept:&MsgNas {N1MsgType:154,N2MsgType:0,N1Msg:&MsgNas_MsgRegistrationAccept
{MsgRegistrationAccept:&ngn_nas.PBRegistrationAccept{ExtendedProtocolDiscriminator:126,SecurityHeaderType:
&SecurityHeaderType{HeaderType:PLAIN_5G_NAS,},MessageIdentity:&MessageType{MessageType:REGISTRATION_ACCEPT,}
,VgsRegistrationResult:&VgsRegistrationResult{EmergencyRegistered:false,NssaaPerformed:false,SmsAllowed:false,
VgsRegistrationResultValue:TGPP_ACCESS,}

Use log tags to tag the logs for specific procedures which are part of a flow or an event. Enabling of AMF logging takes place at different log levels for different log tags.