Can you manually create a vDS after VCF deployment ?

Yes, it is possible to manually create a vDS (vSphere Distributed Switch) after deploying VMware Cloud Foundation but only under certain conditions.

When we deploy VCF on VxRail, we can create only one or two vDS officially during deployment.

The network traffic is split based on the deployment type.
1) System Traffic – Management, vSAN, and vMotion
2) Overlay traffic – Host, Edge, and uplinks

VCF Environment with only one vDS:
vDS -> All system traffic and Overlay traffic is carried on the same vDS.

VCF Environment with two vDS:
vDS1 – Only System traffic
vDS2 – Only Overlay traffic

VCF does support manual creation of an additional vDS but it can be used only for backup or VM traffic.

VCF Environment with one or two vDS but with an additional vDS:
vDS1 – System traffic
vDS2 – Overlay traffic
vDS3 – Backup/VM traffic

How to manually create vDS under VCF:
VCF includes vCenter Server which can be used to create and manage VDS. However, you should be familiar with vSphere networking and the VDS feature before attempting to create one manually, as it can be complex and may have unintended consequences if not done correctly. It is also recommended to consult VCF documentation and best practices before proceeding.

Steps: https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.networking.doc/GUID-D21B3241-0AC9-437C-80B1-0C8043CC1D7D.html

NOTE:

1. The manually created vDS on vCenter cannot be used for system or overlay traffic and is not managed by VMware Cloud Foundation.
2. If you add new hosts to the system, you must manually add them to the vDS.
3. Anything other than VM/backup traffic for the manually created distributed switch is an unsupported config
4. VCF provides a higher level of abstraction and automation to manage the underlying vSphere infrastructure, so while you can create additional VDS switches, it’s not always necessary and sometimes it’s recommended to use the existing VDS switches or other network abstractions provided by VCF such as NSX-T.
5. During VCF upgrade, it is advised to upgrade the vDS manually if needed.

Manually Upgrade the vDS:
Steps: Upgrade a vSphere Distributed Switch to a Later Version (vmware.com)

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