1000v supports up to eight active links in a port-channel. With LACP, there can be 8 active and 8 standby links.
There are a series of compatibility checks that are done before an interface can join a port-channel.
- Speed
- Duplex
- Port Mode
- Access VLAN
- Trunk Native VLAN
- Tagged or Untagged
- Allowed VLAN list
- MTU Size
- SPAN (cannot be a SPAN port)
- Storm Control
Load Balancing
The default method is source MAC address. There are a variety of methods that can be configured
conf t
N1000v-L3(config)# port-channel load-balance ethernet ?
LACP Offload
LACP offload to the VEM module(s) is supported.
N1000v-L3(config)#lacp offload
Pinning
Pinning is a mechanism that allows a vEthernet interface or control/packet VLAN to a specific port channel subgroup. Subgroups are logically smaller port channels which can consist of one or more uplinks to the physical switch. If CDP is enabled on the upstream switch, the subgroups are automatically created.
Note - for virtual Ethernet interfaces Static Pinning can be used - Allows virtual ports behind a VEM to be set to use a specific subgroup within the port channel.
N1000v-L3(config)#port-profile type vethernet STATIC-PIN
N1000v-L3(config)#pinning id <subgroup> backup <subgroup>
There are four methods using in pinning port channels; CDP, Manual, MAC and MAC Relative.
When multiple uplinks are attached to the same subgroup, the upstream switch must be configured in a port channel, the links bundled together.
Command syntax
port-profile type name channel-group auto mode on [sub-group {cdp | manual}] [mac-pinning [relative]]
CDP - If the upstream Switch supports CDP, the CDP option can be used where CDP automatically creates subgroups
N1000v-L3(config)#channel-group auto mode on sub-group cdp
Non CDP - If the upstream Switch does not support CDP, the manual method can be used
N1000v-L3(config)#channel-group auto mode on sub-group manual
MAC Pinning - Used when connecting to multiple upstream switches that do not support port channels. MAC pinning divides the uplinks from the server into standalone links and pins the MAC address of those links using round robin.
N1000v-L3(config)#channel-group auto mode on mac-pinning
MAC Pinning Relative - This uses a scheme where the port channel uses the port number (vmnic number) as the subgroup ID for the Ethernet member port.
N1000v-L3(config)#channel-group auto mode on mac-pinning relative
Network State Tracking for vPC-HM
This feature verifies that L2 connectivity exists and detects link failures.One uplink interface is selected in each subgroup and packets are broadcasted to a tracking VLAN. The packets that are received back are tracked and if the threshold is exceeded, the port channel is considered to be in split mode. In split mode, the interfaces are marked as inactive, and traffic is pinned to active interfaces
Configuration
Single Upstream Switch
port-profile type ethernet SINGLE-SWITCH
channel-group auto mode on
Multiple Upstream Switches
port-profile type ethernet MULTI-SWITCH
! use CDP if supported on upstream switch for automatic subgroup creation
channel-group auto mode on sub-group cdp
! use manual to create the subgroup manually
channel-group auto mode on sub-group manual
! if you use manual, pin using ID on the vEthernet interface
interface Vethernet2
pinning id 2
! use MAC pinning and relative when connecting to upstream switches that do not support port channels
channel-group auto mode on mac-pinning
Network State Tracking
track network-state
track network-state interval 3
N1000v-L3# sh network-state tracking configuration
Tracking mode : enabled
Tracking Interval : 3 sec
Miss count threshold : 5 pkts
Split-network action : re-pin
