By accident, I found a heartbeat/ VLAN issue on a NetScaler cluster at one of my customers. The NetScaler ADC appliances have three interfaces connected to a switch stack. Two of the three interfaces were configured as a channel (LAG). This is a snippet from the config:
set channel LA/1 -tagall ON -throughput 0 -lrMinThroughput 0 -bandwidthHigh 0 -bandwidthNormal 0
bind vlan 10 -ifnum 1/3
bind vlan 10 -ifnum LA/1 -tagged
bind vlan 54 -ifnum LA/1 -tagged
bind vlan 55 -ifnum LA/1 -tagged
On the switch stack, the port to which interface 1/3 is connected, is configured as an access port. The ports, to which the channel is connected, is configured as a trunk port with some permitted VLANs. The customer is using HPE Comware based switches. The terminology is the same for Cisco. If you use HPE ProVision or Alcatel Lucent Enterprise, translate “access” to “untagged” and “trunk” to “tagged”. Because the channel is configured as a trunk port on the switch, the tagall option was set.