[c-nsp] 6500 12.2(33)SXI5+ - cbQosClassMapStats missing entries?

[Bernhard Schmidt]

Hi,

is anyone using the cbQosClassMapStats table from
CISCO-CLASS-BASED-QOS-MIB to get graphs for QoS service policies?

I have two pairs of 6500-class systems that have almost the exact same
configuration (minor differences in firmware versions and IP addresses).
These pairs are

Sup720-3BXL 12.2(33)SXJ2 and Sup720-3BXL 12.2(33)SXI5
ME-C6524GT-8S 12.2(33)SXI4 and ME-C6524GT-8S 12.2(33)SXI7

Those four systems have exactly the same CoPP service policy applied. It
always looks the same

class-map match-any CoPP-critical-in
  match access-group name CoPP-critical-in
  match access-group name CoPP-critical-in-IPv6
class-map match-any CoPP-normal-in
  match access-group name CoPP-normal-in
  match access-group name CoPP-normal-in-IPv6
class-map match-any CoPP-unwanted-in
  match access-group name CoPP-unwanted-in
  match access-group name CoPP-unwanted-in-IPv6
class-map match-any CoPP-default-in
  match access-group name CoPP-default-in
  match access-group name CoPP-default-in-IPv6
class-map match-any CoPP-arp-in
  match protocol arp
class-map match-any CoPP-important-in
  match access-group name CoPP-important-in
  match access-group name CoPP-important-in-IPv6
class-map match-any CoPP-reflexive-in
  match access-group name CoPP-reflexive-in
  match access-group name CoPP-reflexive-in-IPv6

policy-map CoPP-in
  class CoPP-critical-in
  class CoPP-important-in
  class CoPP-reflexive-in
  class CoPP-normal-in
   police 128000 16000 16000 conform-action transmit exceed-action drop 
  class CoPP-unwanted-in
   police 128000 16000 16000 conform-action drop     exceed-action drop 
  class CoPP-arp-in
   police 128000 16000 16000 conform-action transmit exceed-action drop 
  class CoPP-default-in
   police 128000 16000 16000 conform-action transmit exceed-action drop 

Diffs of RANCID backups show this as well as comparison of the live "sh
policy-map control-plane" show they are the same. There are no other
policy-maps configured.

I have a monitoring system (check_mk) that looks at the stats in
cbQosClassMapStats (specifically cbQosCMDropByte and
cbQosCMPostPolicyByte). On the two systems with newer firmware (SXJ2 and SXI7) 
this does not work, I only see four class-maps in the cbQosCMStatsTable
table: normal, unwanted, arp and CoPP-default. The ones for critical,
important, reflexive and cm-default are missing. So it looks like
somewhere between SXI5 and SXI7 classes without a policer don't generate
stats anymore in SNMP. Adding a policer with conform/exceed/violate
transit "fixes" it.

Is this a bug or a feature? Can anyone confirm? I haven't found anything
in the release notes or bug toolkit.

Bernhard