1. On Release 7.x, per-VLAN counter is NOT supported on Nexus 3000. This is because SVI TCAM carving support is NOT available on Nexus 3000 platform and on Release 7.x, SVI TCAM carving support is necessary for per-VLAN counter to function correctly.
Starting with Release 7.0(3)I2(1) and later releases, there is a single image for booting the Cisco Nexus 3000 Series platforms. The kickstart and system images are not required anymore.
The single image binary now boots up on both Cisco Nexus 3000 and 3100 Series platforms and Cisco Nexus 9000 Series platforms.
And On Nexus 9000 platform, per-VLAN counter feature is acheived by carving a new TCAM region for SVI, such behaviour is inherited on Nexus 3000 platform,
Therefore, from Release 7.0(3)I2(1), SVI TCAM carving support is necessary for per-VLAN counter to function correctly.
Please see below for the TCAM carving options of Nexus 3000 Series Platform, we can see that option "SVI" is NOT available:
Nexus_3064(config)# hardware profile tcam region ?
arpacl Configure tcam for arpacl region
e-qos Configure tcam for e-qos region
e-racl Configure tcam for e-racl region
e-vacl Configure tcam for e-vacl region
ifacl Configure tcam for ifacl region
ipsg Configure tcam for ipsg region
ipv6-e-racl Configure tcam for ipv6-e-racl region
ipv6-pbr Configure tcam for ipv6-pbr region
ipv6-qos Configure tcam for ipv6-qos region
ipv6-racl Configure tcam for ipv6-racl region
ipv6-sup Configure tcam for ipv6-sup region
nat Configure tcam for NAT region
pbr Configure tcam for pbr region
qos Configure tcam for qos region
qoslbl Configure tcam for qoslbl region
racl Configure tcam for racl region
sup Configure tcam for sup-tcam region
vacl Configure tcam for vacl region
2. Per-VLAN counter feature is supported on Release 5.x, and it is also supported from day one in Release 6.x
On Release 5.x, it has a section clearly stating SVI and VLAN counters are supported:
3. Although per-VLAN counter is supported on both Release 5.x and Release 6.x, the support is limited. Please see below for the limitations:
Not all multicast packets will be counted, known control plane multicast packets (e.g. OSPF, EIGRP Hello Message etc) are NOT counted as they are punted to the CPU using CoPP queues.
The counter value shown under “In UnicastPackets” counts all packets (including Unicast, Multicast and Broadcast) ingressing on that particular Layer port.
At the time when this article is written, there is no fix or workaround available for Nexus 3000 Series Platform, however,per-VLAN counter featurewill be supported without theabove-mentionedlimitations on Nexus 3100 Series Platform if TCAM is carved for SVI.
Nexus 3000 Series Platform has Broadcom Trident + ASIC
Nexus 3100 Series Platform has Broadcom Trident 2 AISC
The limitation on counting Multicast packets is due to a limitation on ASIC (Broadcom), therefore, it is not a software defect.