CBRS and SNMP with 20.2+

The 20.2 release notes include reference to SNMP strings relating to CBRS. One in question:

smGrantEirp
.1.3.6.1.4.1.161.19.3.1.14.6.1.13
WHISP-APS-MIB-read-only DISPLAYSTRING

snmpget -v2c -c Canopy -m ALL 169.254.1.1 .1.3.6.1.4.1.161.19.3.1.14.6.1.13.0
SNMPv2-SMI::enterprises.161.19.3.1.14.6.1.13.0 = No Such Instance currently exists at this OID

Any idea how I get these to work?

smGrantEirp is part of the whispApsCbrsSmGrant table, which needs to be indexed using two keys. One is the LUID and other is the start frequency of a grant in kHz. For eg: In case of an SM with LUID 2 and having two 10MHz grants of 3600-3610, 3610-3620 MHz, can be indexed using :
.1.3.6.1.4.1.161.19.3.1.14.6.1.13.2.3600000
.1.3.6.1.4.1.161.19.3.1.14.6.1.13.2.3610000

Note that all parameters available in this table are specific to a grant for an SM, hence we need two keys on the AP.

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I understand what you are saying here. What I am trying to do is by SNMP going through one SM at time determine if any are suspended or at reduced power. Is there an easy way to do that? I thought about just checking TX power but some close in SMs will turn TX power down automatically.

Probably the CBSD level status entries, could serve the purpose if I understand it correctly. Determining using per grant status (smGrantEirp) might need some more processing from your end.

To check if its suspended
cbsdStatus : OID : .1.3.6.1.4.1.161.19.3.1.14.3.1.2

To check if there is a EIRP reduction (resulting in Tx power reduction), you could compare the overall requested and granted EIRP for the SM. Note that these are returned as type string and would need to be converted into a floating point type.
cbsdSasEirpRequested : OID : .1.3.6.1.4.1.161.19.3.1.14.3.1.22
cbsdSasEirpGranted : OID : .1.3.6.1.4.1.161.19.3.1.14.3.1.23

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I just get this on all of those:

SNMPv2-SMI::enterprises.161.19.3.1.14.3.1.22.0 = No Such Instance currently exists at this OID

This does work:

snmpget -v2c -c Canopy -m ALL 169.254.1.1 .1.3.6.1.4.1.161.19.3.3.1.6.0
SNMPv2-SMI::enterprises.161.19.3.3.1.6.0 = STRING: “3.6GHz MIMO OFDM - Multipoint - Subscriber Module”

Am I supposed to get this through AP side?

Yes all SM side CBRS status are available on the AP itself. However you need to specify the LUID of the SM since that is a table for all SMs.
e.g. SNMPv2-SMI::enterprises.161.19.3.1.14.3.1.22.2 might work if there is an SM with LUID 2 which forms the last part of the OID.