VMware Networking Community
davidr78
Enthusiast
Enthusiast

Carrying multiple tagged vlans over a vxlan logical switch

Hi,

I'm currently running a test in my lab trying to carry multiple tagged vlans within 1 vxlan logical switch. There is hardly any documentation out there on this feature except for the following:

- NSX 6.2 and later supports "the ability to keep vlan tags over vxlan"

- In order to use the above feature you must enable the <guestVlanAllowed>true</guestVlanAllowed> feature via API (PowerNSX or API tool such as postman)

My understanding is that all the vlan tags are encapsulated within the vxlan packet and therefore don't require any further vlan trunking on the vds or physical switches

This is what i'm testing in my lab:

- NSX 6.4.1

- <guestVlanAllowed>true</guestVlanAllowed> set on the logical switch- 1 vxlan logical switch called logical-net-1

- 1 virtual network device (Cisco ASR) connected to the above logical switch with tagged vlan 10 (sub-interface 10 which will serve as the default gateway for servers)

- 2 windows 2016 server vm's using vmxnet3 and tagged with vlan 10, default gateway is vlan 10 sub-inerface of the asr

If I don't tag within the windows vm's I can ping between the 2 vm's

If I tag vlan 10 within both windows vm's I can't ping between the 2 vm's

The reason why i'm working on this is to actually use a universal logical switch that will stretch between 2 or more sites and provide layer 2 across datacenters.

0 Kudos
2 Replies
cnrz
Expert
Expert

Cross-Vcenter NSX allows to use universal logical switches that span across multiple DCs, so it could be better if possible to use Vxlan logical switches.

If Vlans need to be extended, and L2 VPN could also be an option for Vlan extension between two sites.

For carrying Vlan tags, through a Universal Logical switch, not sure if more than two sites could be used, similar to bridging  for loop prevention mechanisms

0 Kudos
marknguy
Contributor
Contributor

I have the same requirement and tried the same thing you did but it did not work. 

If I use a distributed port group instead of a logical switch, it works fine (make sure you enable VLAN trunking).  Of course you can't stretch L2 the same way on a DPG.

Have you had any success getting this to work since your original post?

0 Kudos