If there are compatibility restrictions between new nodes and the existing nodes in a node pool,
OneFS cannot autoprovision the new nodes. To enable new nodes to join a compatible node pool, add the new node type to the existing node pool. Modify node pool compatibilities using the command-line interface.
Add new node type to existing node pool
For example, suppose that your cluster has an X410 node pool and you add a newer X410 node.
OneFS attempts to autoprovision the new node to the X410 node pool. However, if the new X410 node has different RAM than the older X410 nodes, then
OneFS cannot autoprovision the new node. To provision the new node into the existing X410 node pool, add the new X410 node type to the existing X410 node pool.
Use the
isi storagepool nodetypes list command to view the node types and their IDs, then
isi storagepool nodepools modify <nodepool_name> --add-node-type-ids=<new_nodetype_id>
to add the new node type to the existing node pool.
For example, suppose that your X410 node pool name is x410_nodepool and
isi storagepool nodetypes list shows the new node type ID as 12:
Can you add A300/A3000 nodes to an A200/A2000 node pool?
If you want to add a half chassis of A300 or A3000 to a given cluster of A2000 or A200, what are the requirements? Are you required to add a full chassis of A300 or A3000, or is the option of using a half-populated chassis of A300/A3000 or correspondingly A300L/A3000L feasible?
The answer is that it is possible to add just two nodes, however the drive capacities need to match. In addition, the A300s that you are adding must be configured so that the cache to L3 matches the A200s.
If you are using SSDs for cache, then they do not need to match, because mismatched SSDs perform correctly if you are using L3 cache. See the following table for compatibility requirements.
Compatibility Requirements (to add A300/A3000 nodes to an existing A200/A2000 node pool)
Node type
Compatible
Node Type MLK
Cache Compatibility
Compatibility Requirements
A200/A2000
Yes
A3000L/A300L
Compatible: Nodes are hard coded with L3
SATA disk capacity needs to match
SSD cache disksdo not need to match
A200/A2000
Yes
A3000/A300
Compatible: Nodes must switch cache disks to L3
SATA disk capacity needs to match
SSD cache disks do not need to match
Remove a node type from a node pool
You can also remove a node type from a node pool, for example, if you want to move that node type into its own pool. Using the above example, to remove the X410 nodes with a different RAM capacity and node type ID 12 from the X410 node pool:
Performance considerations and incompatible node types determine compatibility restrictions. For example:
Performance can be affected by adding a particular node type to an existing node pool.
A particular node type can be incompatible with the nodes in an existing pool.
In that case,
OneFS generates a message describing the compatibility issue.
NOTE: SSD compatibilities require that L3 cache is enabled on all nodes. If you attempt to move nodes with SSDs into a node pool on which L3 cache is not enabled, the process fails with an error message. Ensure that L3 cache is enabled for the existing node pool and try again. L3 cache can only be enabled on nodes that have fewer than 16 SSDs and at least a 2:1 ratio of HDDs to SSDs. On Generation 6 nodes that support SSD compatibilities, SSD count is ignored. If SSDs are used for storage, then SSD counts must be identical on all nodes in a node pool. If SSD counts are left unbalanced, node pool efficiency and performance can be less than optimal.
For example, the
PowerScale F200 and F600 node types are incompatible with each other and with previous node types. You cannot add F200 or F600 nodes to a node pool containing any other node types (for example, S210 or F800 nodes). They are not hybrid nodes, so enabling L3 cache is not an option. They can be used as storage only.
The following table shows the compatibilities between specific
PowerScale archive and hybrid nodes. Nodes in the same row of the table are compatible. Compatible nodes can be provisioned into the same node pool. Nodes that are not compatible cannot be provisioned into the same node pool.
PowerScale node
Compatible PowerScale node
A2000
A3000 (OneFS 9.2.1.0 and later)
A200
A300 (OneFS 9.2.1.0 and later)
H400
A300 (OneFS 9.2.1.0 and later)
H500
H700 (OneFS 9.2.1.0 and later)
H5600
H7000 (OneFS 9.2.1.0 and later)
A300 nodes are compatible with A200 and H400 nodes. However, A200 and H400 nodes are not compatible with each other.