esxcli vsan cluster join – Complete Guide with Commands

Learn how to rejoin an ESXi host to a vSAN cluster using esxcli vsan cluster join with clear commands, UUIDs, and complete configuration steps. Our Live Support Team is always here to help you.

esxcli vsan cluster join – Complete Guide with Commands

Reconnecting an ESXi host to a vSAN cluster is a task that needs accuracy. Missing even a small detail can leave your cluster in an inconsistent state. Using the esxcli vsan cluster join command, you can properly attach a host, add disks, or even build a vSAN cluster without vCenter. Below, you will find all the direct commands and steps without skipping anything.

 

Rejoining an ESXi host to a vSAN cluster

First, make sure the ESXi host is running the same version as the rest of the cluster, preserving the vSAN disk partitions. Then configure the vSAN VMkernel port group on the host and reconnect it to vCenter Server.

After that:

1. Connect to one of the active vSAN cluster hosts via SSH.

2. Identify the vSAN Sub Cluster ID:

esxcli vsan cluster get

3. On the rebuilt ESXi host, run the join command with the Sub Cluster UUID:

esxcli vsan cluster join -u sub_cluster_UUID

Example:

esxcli vsan cluster join -u 5230913c-15de-dda3-045e-f4d510a93f1c

4. Confirm that the host is part of the cluster:

esxcli vsan cluster get

Finally, refresh the vSAN status in vCenter to see all hosts marked Healthy.

Creating a new vSAN cluster

Alternatively, you can create a new vSAN master node directly:

esxcli vsan cluster new

esxcli vsan cluster get

Keep the UUID key, as you will use it to join other hosts later.

Listing and adding disks

Disks must be clean of partitions. Use partedutil or zero out the partition info:

sudo dd if=/dev/zero of=/dev/YOUR_DISK_IDENTIFIER bs=1 count=1024

List eligible disks:

vdq -q

Add them to vSAN:

esxcli vsan storage add -d t10.ATA_____ST3250820AS_________________________________________9QE0BJN3 -s naa.55cd2e414cb98556

Check the storage list:

esxcli vsan storage list

Single node operation policies

To allow write operations on a single node, set storage policies:

esxcli vsan policy setdefault -c cluster -p "((\"hostFailuresToTolerate\" i0) (\"forceProvisioning\" i1))"

esxcli vsan policy setdefault -c vdisk -p "((\"hostFailuresToTolerate\" i0) (\"forceProvisioning\" i1))"

esxcli vsan policy setdefault -c vmnamespace -p "((\"hostFailuresToTolerate\" i0) (\"forceProvisioning\" i1))"

esxcli vsan policy setdefault -c vmswap -p "((\"hostFailuresToTolerate\" i0) (\"forceProvisioning\" i1))"

esxcli vsan policy setdefault -c vmem -p "((\"hostFailuresToTolerate\" i0) (\"forceProvisioning\" i1))"

esxcli vsan policy getdefault

Joining data nodes and witness nodes

To add another data node:

esxcli vsan cluster join -u 5218ef34-de66-cc64-1d0e-f14adba2e0e5 -w

esxcli vsan cluster get

To add a witness appliance:

esxcli vsan cluster join -u 5218ef34-de66-cc64-1d0e-f14adba2e0e5 -w -t -p 585b9979-e2ea-89a5-d1fe-a02bb83182fc

esxcli vsan cluster get

Building a vSAN cluster without vCenter

Start by creating a VMKernel interface for vSAN:

esxcli network vswitch standard add -v vSwitch1

esxcli network nic list

esxcli network vswitch standard uplink add -v vSwitch1 -u vmnic5

esxcfg-vswitch -A vSAN vSwitch1

esxcfg-vmknic -a -i 192.168.100.1 -n 255.255.255.0 -p vSAN

esxcfg-vmknic -l

esxcli vsan network ip add -i vmk1

Repeat on all hosts, then create the cluster:

esxcli vsan cluster new

Get the UUID:

esxcli vsan cluster get

Now join other hosts:

esxcli vsan cluster join -u 52bca225-0520-fd68-46c4-5e7edca5dfbd

Finally, claim disks for cache and capacity:

esxcli storage core device list

esxcli vsan storage add -s <naa for cache disk> -d <naa for capacity disk 1> -d <naa for capacity disk 2> -d <naa for capacity disk 3> -d <naa for capacity disk 4>

[If needed, Our team is available 24/7 for additional assistance.]

Conclusion

Using esxcli vsan cluster join correctly ensures that every host connects safely and that storage is properly claimed. By following these commands step by step, you can set up, rejoin, and expand a vSAN environment with confidence.