One of the core functions of the Isilon product is scaling. In it’s physical incarnation you can scale up to 144 nodes with over 50 petabytes in a single namespace. Those limits are because of hardware, as drives and switches get bigger, so can Isilon scale bigger. Even so, you can still start with only three nodes. When nodes are added to the cluster, it increases the storage and performance; existing data is re-balanced across all the nodes after the addition. Likewise, you can remove a node, proactively migrating the data from the leaving node without sacrificing data protection; an excellent way to lifecycle replace your hardware. This tenant of Isilon, coupled with non-disruptive software upgrades, means you there is no pre-set life-span to an Isilon cluster. With SmartPools ability to tier storage by node type, you can leverage older nodes for less frequently accessed data, maximizing your investment.

IsilonSD Edge has that same ability, though slightly muted given you’re limited to six nodes and 36TB (for now hopefully). I wanted to walk through the exercise, to see how node changes are accomplished in the virtual version, which is different from the physical version.

This post is part of a series covering the EMC Free and Frictionless software products.
Go to the first post for a table of contents.

 

Adding a Node

Adding a node to the IsilonSD Edge Cluster is very easy, as long as you have an ESX host with all the criteria ready. If you recall from building our test platform, we built a forth node for this very purpose.

*Note there is no sound, this is to follow along the steps.
  1. In the vSphere Web Client, return to the Manage IsilonSD Cluster tab
  2. Select the cluster (in our case, Isilon01)
  3. Switch to the Nodes tab
  4. Click the + button
  5.  The Management server will again search for candidates if found it will allow you to select them.
  6. Again select the disks and their roles, and then proceed; all the cluster and networking information already exists.

 

Just like creating the cluster, the OVA will be deployed, data stores created (if you used raw disks) and the IsilonSD node brought online. This time the node will be added into the cluster, which will start a rebalance effort to re-stripe the data across all the nodes, including the new one.

Keep in mind, IsilonSD Edge can scale up to six nodes, so if you start with three you can double your space.

Removing a Node

Removing a node is just as straight-forward as adding one, as long as you have four or more nodes. This action can take a very long time, depending on how much data you have, as before the node can be removed from the cluster all the data must be re-striped.

*Note there is no sound, this is to follow along the steps.
  1. In the vSphere Web Client, return to the Manage IsilonSD Cluster tab
  2. Select the cluster (in our case, Isilon01)
  3. Switch to the Nodes tab
  4. Select the node to evict (in our case, node 4)
  5. Click the – (minus) button.
  6. Double check the node and select Yes
  7. Wait until the node Status turned to StopFail

 

During the smart fail operation, should you log onto the IsilonSD Edge Administrator GUI, you’ll notice in the Cluster Overview the node you are removing has a warning light next to it. This is also a good summary screen to gauge the progress of the smartfail, by comparing the % column of the node your evicting, to the other nodes. In the picture below the node we choose to remove now is <1% used, while the other 3 nodes are 4% or 5%, meaning we’re almost there. IsilonSD_RemoveNodeClusterOverview

 

 

Drilling into that node is the best way to understand why it has a warning, there you will see the message that the node is being smartfailed. IsilonSD_RemoveNodeSmartFailMessage

When the smartfail is complete, you still have some cleanup activities.

*Note there is no sound, this is to follow along the steps.
  1. In the vSphere Web Client, return to the Manage IsilonSD Cluster tab
  2. Select the cluster (in our case, Isilon01)
  3. Switch to the Nodes tab
  4. The node you previously set to evict should be red in the Status
  5. Select the node, then click on the trash icon.
  6. This will delete the virtual machine and associated VMDKs

 

If you provided IsilonSD unformatted disks, the data stores the wizard created will still exist and you might want to clean them up. If you want to re-add the node, you’ll need to wait awhile, or restart the vCenter Inventory Service as it takes a bit to update.