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zeebahi
Enthusiast
Enthusiast

NIC Teaming: Standby NIC

Hi everyone.

Please consider following scenario:

VM----PG-A---vSW---vmnic1-------f1-Physical SW

                             |-----vmic2------f2

 

PG A has following NIC teaming policy:

vmnic1 active

vmnic2 standby.

Let say physical SW  transmits a ARP for VM's IP on f2.  What will VSW do next? Will it discard this ARP because it is received on standby vmnic2? Or will it transmit it to VM ?

Thanks and have a good day!!

 

 

       

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3 Replies
a_p_
Leadership
Leadership

With the mentioned settings (even with default failover&teaming), a VM's virtual network adapter will be mapped to a vmnic at power on, and will only send/receive traffic through that vmnic.

André

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zeebahi
Enthusiast
Enthusiast

Thanks for your response!!

But I see different behavior:

Test set up:

ESXI 6.5

Capture-23.PNG

VMNIC2 is active, VMNIC 3 is stand by.

VMNIC2--------gig0/13 Physical SW
VMNIC3--------gig0/14


Physiacl sw set up:
int gig 0/14
switchport mode trunk
switch trunk encapsulation dot1q
switch trunk allowed vlan 24
int vlan 24
ip address 24.24.24.1/24


Ubuntu wire shark machine:
24.24.24.24.24
Ping issued to 24.24.24.24 from physical SW, is send out of gig 0/14, connected standby port VMNIC3.
Ubuntu does see arp packet from  physical  switch

So we do see traffic received on standby uplink is forwarded to attached VM. Is this expected behavior ?

 

Capture-34.PNG

 

 

 

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harry89
Enthusiast
Enthusiast

Do you see mac address of vmnic3 in the capture 

can u use esxtop and type n to see to which network card vm is mapped to

Harry
VCIX-DCV6.5 ,VCIX-NV6 , VCAP-CMA7
Mark answer as correct/helpful if it solves your query
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