Nexus 5596 + SPAN + Port-channel

[kmothukuri]

Hi Experts ,

I have a small doubt regarding the span of ethernet ports , which are part of port-channel on nexus 5596 switch.

As per Cisco documentation , we can SPAN port-channel and only RX traffic can be monitored.

I have 2 port-channels on Nexus 5596 ( VPC+ is configured between nexus 5596-1 and nexus 5596-2 ) as below.

Port-channel 10  - eth 1/1 , eth 1/2 and eth 1/3 (Trunk ports allowed multiple vlans)

Port-channel 11   - Eth 2/1 , eth 2/2 and eth 2/3 (Trunk ports allowed multiple vlans).

I have below questions.

1. Can we configure SPAN for individual ethernet ports, since they are part of port-channels?

2. If yes, can we enable monitor both TX and RX traffic?

If we monitor multiple VLANs (span multiple VLANs), was there any limitations like how many VLANs can be monitored? 

Monitoring is only for RX traffic in case of multiple VLANs monitoring using SPAN.

Please provide me few configuration examples as we got the requirement to configure SPAN for multiple VLANs and individual ethernet ports, which are part of port-channels as above.

[kmothukuri]

OS version of the nexus 5596 switches are 6.2(2a) , does it supports SPAN of port-channles in both directions ?

[balaji.bandi]

below guide will help you :

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/configuration/guide/cli/CLIConfigurationGuide/Span.html

[kmothukuri]

Hi Balaji ,

Thank you for the information.

as per the link shared by you we could see below info.

o configure the source channels for a SPAN session, perform this task:

Command Purpose

switch(config-monitor)# source { interface {port-channel | san-port-channel } channel-number rx | vlan vlan-range | vsan vsan-range}

Configures port channel, SAN port channel, VLAN, or VSAN sources. The monitored direction can only be ingress and applies to all physical ports in the group. For VLAN or VSAN sources, the monitored direction is implicit.

The following example shows configuring a port channel SPAN source:

switch#configure terminal
switch(config)# monitor session 2 
switch(config-monitor)# source interface port-channel 1 rx 

But as per version 6.x guide we could see below info.

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5500/sw/system_management/6x/b_5500_System_Mgmt_Config_6x/b_5500_System_Mgmt_Config_602N12_chapter_010000.html

Configuring Source Port Channels, VSANs, or VLANs

You can configure the source channels for a SPAN session. These ports can be port channels SAN port channels, VSANs and VLANs. The monitored direction can be ingress, egress, or both and applies to all physical ports in the group.

Procedure

  Command or Action Purpose

Step 1	switch# configure terminal	Enters global configuration mode.
Step 2	switch(config) # monitor session session-number	Enters monitor configuration mode for the specified SPAN session.
Step 3	switch(config-monitor) # source {interface {port-channel |san-port-channel } channel-number [rx | tx | both ] | vlan vlan-range | vsan vsan-range }	Configures port channel, SAN port channel, VLAN, or VSAN sources. For VLAN or VSAN sources, the monitored direction is implicit.

Example

The following example shows how to configure a port channel SPAN source:

switch# configure terminal
switch(config)# monitor session 2
switch(config-monitor)# source interface port-channel 1 rx
switch(config-monitor)# source interface port-channel 3 tx
switch(config-monitor)# source interface port-channel 5 both ------> Both tx and rx monitoring is done
switch(config-monitor)#

Looks like OS 6.2 supports SPAN of port-channel is both directions ,
Can someby please confirm it ?