Scaling out vSAN cluster Compute, File Service Shares and iSCSI Target Service.

Hello Everyone,

Today, we are going to cover up how to scale out the vSAN cluster compute, Storage, File Service Shares and iSCSI Target service.

In my case, I have a cluster of 4 hosts running on vSphere 7 and vSAN 7 and I want to add a new host (ESXi05) to my existing vSAN cluster, expand the vSAN Data store and also expand my vSAN File Services cluster.

Before going forward on this, we need to make sure that this new ESX host has same configuration like the existing ones in terms of CPU, RAM, Network and Disk.

First of all, when you add a host into the cluster you need to make sure that it should be in maintenance mode. If it is not in maintenance mode then vSAN FS will instantly try to clone a vSAN File Services agent VM (FS VM) on it and that process will fail as there’s no disk group yet.

After you added it to the cluster, you have to create the disk group first. Claim all the disks that need to be part of the disk group and create the disk group. When you have done that you can take the host out of maintenance mode. 

Let's do it quickly.

1. Go to the cluster.

2. Add the new host(ESXi05) into the cluster.

3. Add this new ESX hosts in all DvSwitch like other other ones.

Now, it is time to create the disk group for this new host.

1. Click on cluster >> click on Configure then go to vSAN section and choose Disk Management and click on "CLAIM UNUSED DISKS"

Select the disks on this new host for Cache and Capacity tier as shown below.

Click on CREATE and few tasks will initiate on vCenter for disk group creation.

Once the disk group created, vSAN datastore capacity will increase  automatically.

However, one thing you will need to do is expand the IP Pool for the vSAN FS Protocol Stack container. 

• Go to your cluster
• Click on vSAN / Services
• Go to File Service and click Edit on the right
• Go to the IP Pool page by clicking Next twice
• Add that additional IP address and DNS Name

• Click Next / Finish

Exit this new host from Maintenance mode now.

A task will initiate for install a new vSAN File Service Node/Agent on this new ESX host.

So, all looks good.

Now, you can increase the File share size as  the vSAN datastore has enough space available.

Since, vSAN datastore has enough free space available, you can also create/expand iSCSI LUNs if you have enabled iSCSI on vSAN cluster as well.

So, in this post, we have scale out vSAN compute (by add new host with CPU,RAM), vSAN Storage (Add new disks group) as well.

That's all. Have a great day ahead and Cheers..