How to configure vSAN VMkernel networking
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How to configure vSAN VMkernel networking

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Article ID: 315554

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Updated On:

Products

VMware vSAN

Issue/Introduction

This article provides steps to configure the VMkernel network for vSAN prior to running the vSAN setup wizard in vCenter.

Environment

VMware vSAN 6.1.x
VMware vSAN 8.0.x
VMware vSAN 7.0.x
VMware vSAN 5.5.x
VMware vSAN 6.2.x
VMware vSAN 6.0.x
VMware vSAN 6.5.x

Resolution

Configuring vSAN VMkernel networking on a standard virtual switch

To configure vSAN VMkernel networking on a standard virtual switch:
  1. Open the vSphere Web Client.
  2. Go to the Hosts and Clusters view.
  3. Select the host you want to configure for vSAN.
  4. Click the Manage/Configure tab.
  5. Click Networking.
  6. Select VMkernel Adapters from the dropdown.
  7. Click the Add host networking icon and click Next.
  8. In the Select target device page, select either an existing standard switch or a new vSphere standard switch and click Next.

    Note: If you create a new standard switch, ensure that you attach sufficient physical NICs to the vSwitch.
     
  9. In the Port properties page, select Virtual SAN traffic/vSAN, configure the settings for the VMkernel adapter, and enter appropriate values in these required fields:
     
    • Network label – Enter a label. For example, Virtual SAN.
    • VLAN ID – If you are using VLANs to separate vSAN traffic, enter the relevant VLAN ID.
    • IP Settings – Enter the desired IPv4 network details (DHCP, if applicable).
    • TCP/IP stack – Select the relevant TCP/IP stack.

      For more information on multiple TCP/IP stacks, see VMkernel Networking Layer.  
  10. Click Next.
  11. Review your settings, then click Finish.
  12. Repeat Steps 3 to 10 for each host that is a member of the vSAN cluster.
  13. After all hosts are configured, configure your vSAN Cluster. For more information, see Enabling or disabling a vSAN cluster (2058322).
 

Configuring vSAN VMkernel networking on a distributed virtual switch

To configure vSAN VMkernel networking on a distributed virtual switch:
  1. Open the vSphere Web Client.
  2. Go to the Networking view.
  3. Navigate to the distributed switch you want to modify
  4. Select Manage host networking and click Next.
  5. Click Attached hosts and select from the hosts that are associated with the distributed switch.
  6. Click Next.
  7. Select Manage VMkernel adapters and click Next.
  8. Click New adapter.
  9. In the Select target device page of the Add Networking wizard, select an existing distributed port group, and click Next.
  10. In the Port properties page, select Virtual SAN traffic/vSAN, configure the settings for the VMkernel adapter, and enter appropriate values for these required fields:
     
    • Network label – Enter a label. For example, Virtual SAN.
    • VLAN ID – If you are using VLANs to separate vSAN traffic, enter the relevant VLAN ID.
    • IP Settings – Enter the desired IPv4 network details (DHCP, if applicable).
    • TCP/IP stack – Select the relevant TCP/IP stack.
       
  11. Click Next.
  12. Review your settings and then click Finish.

    You can now enable your vSAN cluster.
Note:
  • The vSAN VMkernel Network should not be used for any kind of external storage (NFS iSCSI, etc) or vMotion traffic. It may cause uneven performance, VM hung, and Host Non-responsive issues.
  • The vSAN data traffic traverses through the dedicated physical network adapters allocated to the VMkernel of vSAN which requires 10 GB or higher dedicated network to work efficiently.
    The routing between the switches connected to the vSAN network may cause reduced bandwidth, resulting in an impact on VMs performance.
     


Additional Information

 
When troubleshooting connectivity between VSAN nodes, it is useful to use the netcat command (nc -z) to test that ports are open between nodes.
 
For example:  
  • In a recent case, a 7th ESXi host was added to the VSAN cluster. 
  • Although the VSAN cluster command line showed that the new node was participating in the cluster, workloads would not move to the new node, and re-balancing did not take place.
  • Entering the "nc -z aa.bb.cc.dd 12321" (where aa.bb.cc.dd was the IP address of the newly added nodes), immediately caused re-balancing to occur and the VSAN cluster began to operate with all 7 nodes functioning as expected.  

The VSAN required ports can be found at https://ports.esp.vmware.com/home/vSAN