I am very confused on how to get accurate readings for SNR and other statistics on a per-interface basis on the Cisco CMTS platform.
Here is the problem: I get the cable interface information, and use that same ID to correlate and walk
DOCS-IF-MIB:docsIfSigQSignalNoise
The problem is this upstream channel is really down so I do not understand why it is reporting a value for SNR
$ snmpwalk 1.3.6.1.2.1.2.2.1.2.190510
IF-MIB::ifDescr.190510 = STRING: Cable1/0/0-upstream6
$ snmpwalk 1.3.6.1.2.1.10.127.1.1.4.1.5.190510
SNMPv2-SMI::transmission.127.1.1.4.1.5.190510 = INTEGER: 286
CBR8_CMTS#sh int cable 1/0/0 upstream 6
MAC domain upstream impairment report: 0x0
Cable1/0/0: Upstream 6 is up
Description:
Received 120227940 broadcasts, 16231561 multicasts, 28442379 unicasts
108275 discards, 1939920 errors, 0 unknown protocol
164901880 packets input
Codewords: 4130183473 good 83486120 corrected 13856708 uncorrectable
0 noise, 0 microreflections
Total NON-MTC Modems On This Upstream Channel : 19 (18 active)
Total MTC Modems On This Upstream Channel : 88 (88 active)
CBR8_CMTS#sh controllers upstream-Cable 1/0/0 us-channel 6
Controller 1/0/0 upstream 6 AdminState:DOWN Opstate: DOWN (Reason: Default)
Frequency NA, Channel Width 1.600 MHz, Symbol Rate 1.280 Msps
