DOCSIS Device Event Log¶

Provides Access To A Cable Modem’s Device Event Log For Operational And Troubleshooting Insight (Ranging, T3/T4, Profile Changes, CM-Status).

Endpoint¶

POST /docs/dev/eventLog

Request¶

Use the SNMP-only format: Common → Request TFTP parameters are not required.

Response¶

This endpoint returns the standard envelope described in Common → Response (mac_address, status, message, data).

data.logs is an array of log entries reported by the device.

Abbreviated Example¶

{
  "mac_address": "aa:bb:cc:dd:ee:ff",
  "status": 0,
  "message": null,
  "data": {
    "logs": [
      {
        "docsDevEvFirstTime": "2025-10-19T18:39:24",
        "docsDevEvLastTime": "2025-10-19T18:39:24",
        "docsDevEvCounts": 1,
        "docsDevEvLevel": 6,
        "docsDevEvId": 67061601,
        "docsDevEvText": "US profile assignment change.  US Chan ID: 42; Previous Profile: 12; New Profile: 11.;CM-MAC=aa:bb:cc:dd:ee:ff;CMTS-MAC=aa:bb:cc:dd:ee:ff;CM-QOS=1.1;CM-VER=4.0;"
      },
      {
        "docsDevEvFirstTime": "2025-10-19T18:40:09",
        "docsDevEvLastTime": "2025-10-19T18:40:09",
        "docsDevEvCounts": 3,
        "docsDevEvLevel": 6,
        "docsDevEvId": 74010100,
        "docsDevEvText": "CM-STATUS message sent.  Event Type Code: 5; Chan ID: 13; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=aa:bb:cc:dd:ee:ff;CMTS-MAC=aa:bb:cc:dd:ee:ff;CM-QOS=1.1;CM-VER=4.0;"
      },
      {
        "docsDevEvFirstTime": "2025-10-19T18:41:24",
        "docsDevEvLastTime": "2025-10-19T18:49:14",
        "docsDevEvCounts": 35,
        "docsDevEvLevel": 6,
        "docsDevEvId": 74010100,
        "docsDevEvText": "CM-STATUS message sent.  Event Type Code: 5; Chan ID: 13; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=aa:bb:cc:dd:ee:ff;CMTS-MAC=aa:bb:cc:dd:ee:ff;CM-QOS=1.1;CM-VER=4.0;"
      },
      { "...": "additional log entries elided" }
    ]
  }
}

Response Field Details¶

Field	Type	Description
`mac_address`	string	MAC address of the cable modem returned in the common envelope.
`status`	int	Operation status (`0` = success; non-zero indicates failure).
`message`	string	Human-readable status or error message (nullable).
`data.logs`	array	Array of device log entry objects.
`docsDevEvFirstTime`	string	First occurrence of the event (ISO-8601 timestamp).
`docsDevEvLastTime`	string	Most recent occurrence of the event (ISO-8601 timestamp).
`docsDevEvCounts`	int	Number of times the event has occurred.
`docsDevEvLevel`	int	Syslog-style severity (`0`=Emergency, `1`=Alert, …, `7`=Debug; lower = more critical).
`docsDevEvId`	int	Numeric event identifier.
`docsDevEvText`	string	Human-readable message; often includes CM/CMTS MACs, profiles, versions.

Common Event Codes¶

Event ID	Description
67061601	US profile assignment change.
74010100	CM-STATUS message sent.
74010200	Ranging request sent.
74010300	Ranging response received.
74020100	T3 timeout occurred.
74020200	T4 timeout occurred.
74030100	Upstream channel change completed.
74030200	Downstream channel change completed.
74040100	Ranging success.
74040200	Ranging failure.
74040300	Ranging aborted.
74050100	Power adjustment performed.
74060100	Cable modem reset (power cycle).
74060200	Firmware download initiated.
74060300	Firmware download completed.

CM STATUS¶

Event Type Code	Description
0	Reserved (no use)
1	Secondary Channel MDD Timeout (the MDD timer on a secondary channel expired)
2	QAM / FEC Lock Failure (loss of QAM or Forward Error Correction lock on downstream)
3	Sequence Out-of-Range (a packet sequence number was out of the expected range)
4	Secondary Channel MDD Recovery (receipt of MDD on a secondary channel)
5	QAM / FEC Lock Recovery (channel regained lock)
6	T4 Timeout (station maintenance / broadcast failure)
7	T3 Retries Exceeded (ranging retries maximum exceeded)
8	Successful Ranging After T3 Retries Exceeded (ranging recovery)
9	CM Operating on Battery Backup (loss of A/C power for > 5 seconds)
10	CM Returned to A/C Power (came back from battery to A/C)
11	MAC Removal Event (one or more MAC addresses removed, e.g., in port transition)
12-15	Reserved for future use
16	DS OFDM Profile Failure (FEC errors exceeded limit on a downstream OFDM profile)
17	Primary Downstream Change (lost primary downstream, switched to backup)
18	DPD Mismatch (Some mismatch in DPD change count vs NCP odd/even bit)
20	NCP Profile Failure (FEC errors exceeded limit on NCP profile)
21	PLC Failure (FEC errors exceeded on PLC)
22	NCP Profile Recovery (FEC recovered on NCP)
23	PLC Recovery (FEC recovery on PLC channel)
24	OFDM Profile Recovery (FEC recovery on OFDM profile)
25	OFDMA Profile Failure (modem unable to support a received profile)
26	MAP Storage Overflow (maps in CM overflow buffer)
27	MAP Storage Almost Full
28-255	Reserved / for vendor extensions

Notes¶

Event levels follow syslog conventions: 0 (Emergency) … 7 (Debug).
Entries are semi-structured; downstream analytics may parse docsDevEvText for fields like channel IDs, profiles, and MACs.
Devices may cap or rotate stored logs; poll and archive if long-term history is required.