swapnode

Use the swapnode command to facilitate maintenance actions that maintain availability without interruptions by using virtualized target ports on a hot spare node. This command is used during hardware replacement procedures, or as alternative to place a node in service state.

Syntax

Parameters

-service | -failover | -failback | -replace

(Required) Specifies the type of service action is being performed on a selected node. The values are:

-service: puts an active online node into service state after the system triggers a failover of N_Port ID Virtualization (NPIV) ports to the partner node in the I/O group. This command can succeed whether or not spare protection is available.
-failover: fails over a clustered node to a standby spare, even if the clustered node is online. The specified node moves into service and the standby spare becomes an online_spare. The command can succeed with or without the optional -spare parameter. When used with the -spare parameter, it defines the standby spare to be used; otherwise, the best fit standby spare node is chosen.
-failback: fails back an online_spare to a standby spare, and the node it protects exits the service mode and returns to the cluster. You must specify the node object ID or name of the online_spare for this command.
-replace: replaces a specified node that is logically offline or in a service state with a candidate node whose WWNN matches the specified node.
Note: This -replace parameter is used in hardware upgrade procedures or when directed by (and along with) IBM support to recover node that is reporting in error code 578 (loss of hardened data).

-force

(Optional) Specifies that a node be removed, even if disruption to host system I/O might occur as a result.

Important: Specifying -force might result in a loss of access. Use it only under the direction of your product support information.

-spare node_id | node_name

(Optional) Specifies the ID or name of the standby spare to be brought online as a temporary stand-in. This parameter can be used only with -failover parameter.

Note: The value for the ID must be greater than 1 because the spare is never the first node in the clustered system.

node_id | node_name

(Required) Specifies the node ID or name that is being swapped or serviced.

Description

Use the swapnode command to facilitate the maintenance actions by failing over a specified node to a hot spare and maintaining availability without interruptions on its virtualized target ports, failing back an online spare to a standby spare, and returning the original node to the cluster. This command can also be used during hardware replacement procedures to complete tasks that require the rmnode and addnode commands or as an alternative to placing a node in service state.

The -replace parameter simplifies the process (commands) required to replace an offline or service node, which is protected by an online_spare. It uses the I/O group and site values that are associated with the offline node as configuration parameters for the replacement. The replacement node must be a candidate node with the same WWNN value as the offline node.

Note: The WWNN of a new replacement candidate node must be changed only to the WWNN of a logically offline node, or node in service state, when that node is physically powered off and disconnected from the system.

Important: NVMe virtualized target ports are not supported on some Fibre Channel adapters. Before you use the CLI, check the spare node configuration. Allows the user to download the cloud usage history.

Note: This command is available during the upgrade process.

An invocation example

The following example lists the steps to put a node into service mode.

Use the lsnode command to list all the nodes in the system. In the following example of lsnode output, the node "node2" with ID 2 is in online state.

lsnode

The resulting output:

id name  UPS_serial_number WWNN             status IO_group_id IO_group_name config_node UPS_unique_id hardware iscsi_name                                        iscsi_alias panel_name enclosure_id canister_id enclosure_serial_number site_id site_name 
1  node1                   500507680C000128 online       0           io_grp0       yes                       SV1      iqn.1986-03.com.ibm:2145.mcr-cay-cluster-23.node1             G71H00P                 1 
2  node2                   500507680C000130 online       0           io_grp0       no                        SV1      iqn.1986-03.com.ibm:2145.mcr-cay-cluster-23.node2             G71H00M                 1
3  spare1                  500507680C000138 online_spare 1           io_grp1       no                        SV1      iqn.1986-03.com.ibm:2145.mcr-cay-cluster-23.node3             G71H00X                 1

Issue the swapnode -service command with the ID or name of the node. The following example changes the node with ID 2 to the service mode.
```
swapnode -service 2
```
The detailed resulting output:
```
No feedback
```

Use lsnode command to verify that the node is in the service state. The following example shows the node "node 2" with ID 2 is in service state.

lsnode

The resulting output:

id name  UPS_serial_number WWNN             status IO_group_id IO_group_name config_node UPS_unique_id hardware iscsi_name                                        iscsi_alias panel_name enclosure_id canister_id enclosure_serial_number site_id site_name 
1  node1                   500507680C000128 online       0           io_grp0       yes                       SV1      iqn.1986-03.com.ibm:2145.mcr-cay-cluster-23.node1             G71H00P                 1 
2  node2                   500507680C000130 service      0           io_grp0       no                        SV1      iqn.1986-03.com.ibm:2145.mcr-cay-cluster-23.node2             G71H00M                 1
3  spare1                  500507680C000138 online_spare 1           io_grp1       no                        SV1      iqn.1986-03.com.ibm:2145.mcr-cay-cluster-23.node3             G71H00X                 1