CL Command Reference - CRTCRG
CL Command List > CRTCRG Reference
Description:
The Create Cluster Resource Group (CRTCRG) command creates a cluster resource group object. The cluster resource group serves as the control object for a collection of resilient resources. It identifies a recovery domain, which is a set of nodes in the cluster that will play a role in the recovery. Additional characteristics for the cluster resource group, such as the exit program that will be called to perform resource specific processing. The cluster resource group exit program will be called with an action code of Initialize after each group has been created on each node in the recovery domain, if an exit program is specified for the cluster resource group. Successful completion of this command results in a new job started in the QSYSWRK subsystem. This job has the same name as the name of the cluster resource group being created.
To change attributes of the cluster resource group use the Change Cluster Resource Group (CHGCRG) command.
This command will do the following:
. Create the cluster resource group object on all nodes in the recovery domain. The cluster resource group may be accessed by a cluster resource group command running on any node in the cluster.
. Provide users a single system image of the cluster resource group object. That is, any changes made to the cluster resource group will be made on all nodes in the recovery domain.
. Call the cluster resource group exit program with an action code of Initialize after the cluster resource group has been created on each node in the recovery domain, if an exit program is specified for the cluster resource group. The cluster resource group status will be set to Initialize Pending. If the exit program fails, the cluster resource group object is deleted from all nodes in the recovery domain.
. If the exit program is successful, the cluster resource group status is set to Inactive. To change the cluster resource group status to Active, use the Start Cluster Resource Group (STRCRG) command.
. After the exit program is called, this command verifies the queue (CRGMSGUSRQ parameter), used by the Distribute Information (QcstDistributeInformation) API, exists if one was specified. The distributed information user queue must be created with pointer capable messages disabled. This means that pointers are not allowed within the message content.
. After the exit program is called, this command verifies the failover message queue and library on all recovery domain nodes if one was specified.
Restrictions:
1. You must have input/output system configuration (*IOSYSCFG) special authority to run this command.
2. This command cannot be called from a cluster resource group exit program.
3. The cluster resource group name cannot begin with QCST.
4. Cluster Resource Services must be active on the node processing the request.
5. All nodes in the recovery domain must be in the cluster with a status of Active.
6. The cluster resource group exit program must exist on all nodes in the recovery domain if an exit program is specified. It must have the same name and be in the same library on each node.
7. Each node can be specified only once in the recovery domain.
8. The cluster resource group name cannot be used by an existing cluster resource group on any node in the cluster.
9. For application cluster resource groups, the following restrictions apply to the specified takeover IP address:
a. If Cluster Resource Services configures the takeover IP address, all nodes in the recovery domain must be in the same subnet (network address) and the subnet defined on all nodes in the recovery domain.
b. The takeover IP address must be unique. If Cluster Resource Services is responsible for configuring the takeover IP address, it will be added to each node in the recovery domain.
c. The takeover IP address must not be active on any node in the recovery domain.
10. For device cluster resource groups:
a. Only auxiliary storage pool devices are supported.
b. All nodes in the recovery domain must belong to the same device domain.
c. The configuration objects, such as device descriptions, for the devices specified for the cluster resource group must exist on all nodes in the recovery domain and the resource name specified in a configuration object must be the same on all nodes in the recovery domain.
d. If a site name is specified, then a data port IP address must be specified. The reverse applies too, if a data port IP address is specified, then a site name must be specified.
e. If a data base is specified in a configuration object, it must be the same on all nodes in the recovery domain.
f. The server takeover IP address must be unique. It can only be associated with a primary auxiliary storage pool.
g. The same configuration object cannot be specified for more than one cluster resource group.
h. Devices attached to the same input/output processor (IOP) or high-speed link input/output (I/O) bridge can be specified for only one cluster resource group.
i. If devices attached to different IOPs or high-speed link I/O bridges are grouped such as for an auxiliary storage pool, all devices for the affected IOPs or high-speed link I/O bridges must be specified in the same cluster resource group.
j. The IOP or high-speed link I/O bridge controlling the devices specified in a cluster resource group must be accessible by all nodes in the cluster resource group¡¯s recovery domain. This is verified if sufficient hardware configuration has been performed so that all nodes are aware of the new hardware. If hardware configuration is incomplete, this is verified when the Start Cluster Resource Group (STRCRG) command is called.
k. If configuration objects are specified and the primary node does not currently own the devices, this command fails with an error message.
l. A cluster resource group may be created with no device entries. Device entries must be added using the Add Cluster Resource Group Device Entry (ADDCRGDEVE) command before the cluster resource group can be started.
m. If the cluster resource group contains any members of an auxiliary storage pool group, it must contain all members before the cluster resource group can be started. All members do not have to be specifed when the cluster resource group is created. Additional members can be added with the Add Cluster Resource Group Device Entry (ADDCRGDEVE) Command. If the auxiliary storage pool group exists and clustering can determine the members of the group, a warning message is sent if any members were not specified.
n. If the configuration objects specified are for remote independent auxiliary storage pool mirroring, each node in the recovery domain may have a site name and up to 4 data port IP addresses. There can be at most 2 different site names amongst the nodes. If a site name is specified, at least one data port IP address must be specified too. The reverse is also true. If one or more data port IP address is specified, a site name must be specified too.
o. If CPFBB5F message is received, make sure the cluster version is 4 and not 3 when specifying the site name field.
Examples:
Example 1: Creating a CRG with a Two-Node Recovery Domain
CRTCRG CLUSTER(MYCLUSTER) CRG(MYCRG) CRGTYPE(*DEV)
EXITPGM(TEST/EXITPGM) USRPRF(USER1)
RCYDMN((NODE01 *PRIMARY) (NODE02 *BACKUP *LAST))
CFGOBJL(*NONE) TEXT(¡¯IASP for Application 17¡¯)
This command creates a device cluster resource group called MYCRG in the cluster called MYCLUSTER. The recovery domain consists of two nodes. NODE01 is the primary and NODE02 is the only backup. The list of configuration objects is not specified on this command; the Add CRG Device Entry (ADDCRGDEVE) command can be used to add this information.
Example 2: Creating a CRG with a Single-Node Recovery Domain
CRTCRG CLUSTER(MYCLUSTER) CRG(MYCRG) CRGTYPE(*DEV)
EXITPGM(TEST/EXITPGM) USRPRF(USER1)
RCYDMN((NODE01 *PRIMARY *LAST MYSITE (¡¯1.1.1.1¡¯
¡¯2.2.2.2¡¯)))
EXITPGMFMT(EXTP0200)
TEXT(¡¯IASP for Application 17¡¯)
This command creates a device cluster resource group called MYCRG in the cluster called MYCLUSTER. The recovery domain consists of one node, NODE01. The recovery domain sets NODE01 as the primary node in site MYSITE, with 2 data port IP addresses, 1.1.1.1 and 2.2.2.2.
Example 3: Creating a Peer CRG with a Two-Node Recovery Domain
CRTCRG CLUSTER(MYCLUSTER) CRG(MYPEER) CRGTYPE(*PEER)
EXITPGM(TEST/EXITPGM) USRPRF(USER1)
RCYDMN((NODE01 *PEER) (NODE02 *PEER))
APPID(CompanyName.ExPeer)
TEXT(¡¯Peer for ExamplePeer Application¡¯)
This command creates a peer cluster resource group called MYPEER in the cluster called MYCLUSTER. The recovery domain consists of two nodes, NODE01 and NODE02. This cluster resource group is for an IBM shipped application called ExamplePeer.