SDDC Manager Host Commissioning and vSAN Cluster Addition Failure Due to Stale Networking and Faulty Uplink

Products

• VMware vSAN

Issue/Introduction

Symptoms:

• When adding a ESXi host to the VSAN cluster using SDDC manager, the "Create vSAN disk groups" step fails at 64% citing vSAN cluster validation failures.

  

  

• The ESXi host is decommissioned and disconnected from the vcenter server and attempts to recommission the host fails with the below error message

  Found [] portgroups on vSphere standard switch. Allowed portgroups must be [Management Network]


• The SDDC manager prerequisites requires only "Management network" port group on the standard switch of the ESXi host prior to commissioning. However, the ESXi host is missing the default "Management Network" portgroup on the standard switch and retains stale Distributed Virtual Switch (DVS) entries despite being decommissioned from the vcenter server.

  From the host client networking view, it is observed that the host has stale DVS entries.

  

• Restoring the network configurations on the ESXi host by logging into the DCUI and using the network restore options removes all the stale DVS entries and creates the "Management Network" port group on the standard switch 

  

• Commissioning the host using SDDC manager completes successfully after restoring the network configurations to standard switch

  

• However, adding ESXi host to cluster is stuck at 64%

• From the vcenter server, it is observed that the disk groups are created successfully on the newly added ESXi host

  

• However, the VSAN cluster skyline health is unhealthy and reports below issues and the newly added host is partitioned from the rest of the cluster

  - vSAN Basic (unicast) connectivity check

  - vSAN MTU check (ping with large packet size)

  - vSAN cluster partition

  

Environment

VMware Cloud Foundation 9.0

ESXi 8.x

Cause

The newly added ESXi host has a faulty physical uplink which is dropping packets. Even if the MTU is correctly configured uniformly across the environment, the hardware-level drops prevent consistent communication between the new host and the existing vSAN cluster, leading to a partitioned state and SDDC manager VSAN cluster validation failures.

Cause Validation:

• The /var/log/vmware/vcf/domainmanager/domainmanager.log explicitly indicates the ESXi host is partitioned.

2026-05-07T07:03:41.711+0000 DEBUG [vcf_dm,69fc394d62ac929da10bff76d3fa4024,cda3] [c.v.e.s.c.c.v.vsan.VsanManagerBase,dm-exec-11]  VSAN Cluster Status: VsanClusterStatusInfo(numberOfDataDisksInUse=0, numberOfDataDisksEligible=0, numberOfSsdDisksInUse=15, numberOfSsdDisksEligible=15, numberOfHostsInUse=7, lowestNumberOfHostsInClusterNode=6, numberOfHostsInClusterNode=7, pendingObject=<Host fqdn> :PARTITIONED, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, healthVersionInconsistent=false, resourcesAvailable=false)
2026-05-07T07:03:41.711+0000 INFO  [vcf_dm,69fc394d62ac929da10bff76d3fa4024,cda3] [c.v.e.s.c.c.v.vsan.VsanManagerBase,dm-exec-11]  Waiting for a minute to check value: <Host fqdn>:PARTITIONED, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS. Previous pending resource: <Host fqdn>:PARTITIONED, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS,<Host fqdn>:NO_DISKS, <Host fqdn>:NO_DISKS

• vmkping tests to other hosts in the VSAN cluster fails with 100% packet loss

vmkping -I vmk2 -s 1472 -d 10.#.#.#
PING 10.#.#.# (10.#.#.#): 1472 data bytes
sendto() failed (Host is down)

vmkping -I vmk2 -s 8972 -d 10.#.#.#
PING 10.#.#.# (10.#.#.#): 8972 data bytes
sendto() failed (Host is down)

• Executing esxcli network nic stats get -n vmnic# reveals non-zero and increasing values for Receive packets dropped for the uplink used for VSAN connectivity
  
  NIC statistics for vmnic#:
      Packets received: 2220301727
      Packets sent: 1285993360
      Bytes received: 16129589577444
      Bytes sent: 2240189130524
      Receive packets dropped: 83
      Transmit packets dropped: 0
      Multicast packets received: 17110
      Broadcast packets received: 2419
      Multicast packets sent: 4539
      Broadcast packets sent: 569
      Total receive errors: 0
      Receive length errors: 0
      Receive over errors: 0
      Receive CRC errors: 0
      Receive frame errors: 0
      Receive FIFO errors: 0
      Receive missed errors: 0
      Total transmit errors: 0
      Transmit aborted errors: 0
      Transmit carrier errors: 0
      Transmit FIFO errors: 0
      Transmit heartbeat errors: 0
      Transmit window errors: 0

Resolution

To address this issue, engage your fabric vendor and replace the faulty physical uplink

As a workaround, administratively take the faulty uplink down to force traffic to a healthy standby uplink using the below command

esxcli network nic down -n vmnic#