Defining_cluster_nodes_on_System_P

• Defining Cluster Nodes
  • Using the mkdef command
  • Using an xCAT stanza file
  • Discovering and defining pre-existing LPARs
    • Using rscan to discover LPARs
    • Using mkdef after rscan
  • Creating new LPARs and node definitions
    • Define the nodes
    • Create new LPARs using mkvm
  • Using a cluster configuration file.
  • Discover HMCs/frame/CECs, and define them in xCAT DB
    • Using the lsslp command

Defining Cluster Nodes

There are several ways to create xCAT cluster node definitions. Use the method listed below that best fits your situation.

Using the mkdef command

You can use the xCAT mkdef command to create basic xCAT node definitions.

For example:

    mkdef -t node -o clstrn27 mgt=hmc os=AIX nodetype=ppc,osi hwtype=lpar groups=lpar,all,compute

To get a description of all the valid attributes that may be specified for a node definition you can run the lsdef command as follows.

    lsdef -t node -h | pg

See the mkdef man page for more examples. (mkdef )

Using an xCAT stanza file

A stanza file contains information that can be used to create xCAT data object definitions. A stanza file can be used as input to several xCAT commands. The stanza file contains one or more stanzas that provide information for individual object definitions.

For example, a node definition stanza could look like the following.

    compute02:
       objtype=node
       groups=lpar,all,compute
       hcp=c98m6hmc01
       id=102
       mac=163D0D02C202
       mgt=hmc
       nodetype=ppc,osi
       hwtype=lpar
       os=AIX

See the xcatstanzafile man page for more information and examples. (xcatstanzafile )

Once you have created a stanza file you can pass the information to the mkdef command as follows.

    cat mystanzafile | mkdef -z

Discovering and defining pre-existing LPARs

Using rscan to discover LPARs

This method assumes that LPARs were already created using the standard HMC interfaces or the xCAT System p Direct FSP Management (xCAT DFM) support.

Use the xCAT rscan command to collect node information from one or more hardware control points.

The following example uses the "-z" option to create a stanza file that contains the information gathered by rscan. The information in the stanza file will also include some default values that could be used for the node definitions. (See the rscan man page for more information. rscan)

To write the stanza formated output of rscan to a file called "mystanzafile" run the following command.

    rscan -z hmc01 > mystanzafile

This file can then be checked and modified as needed. For example you may need to add a different name for the node definition or add additional attributes and values etc.

Note: The stanza file may contain stanzas for objects other than the LPARs. This information must also be defined in the xCAT database. It is not necessary to modify the non-LPAR stanzas in any way.

Using mkdef after rscan

The information gathered by the rscan command can be used to create xCAT node definitions.

Since we have put all the node information in a stanza file we can now pass the contents of the file to the mkdef command to add the definitions to the database.

    cat mystanzafile | mkdef -z

You can use the xCAT lsdef command to check the definitions (ex. "lsdef -l node01"). After the node has been defined you can use the chdef command to make any additional updates to the definitions, if needed.

Creating new LPARs and node definitions

You can use the xCAT mkvm command to create additional logical partitions.

See the mkvm man page for more details and usage. (mkvm)

Also see the following for a description of using mkvm with the xCAT DFM support. [xCAT_System_p_Hardware_Management_for_DFM_Managed_Systems]

Define the nodes

Before running the mkvm command you must define the corresponding xCAT node definitions.

At a minimum the "mgt" and "groups" attribute of the node definitions must be set.

For example, to create a set of new node definitions you could run a command similar to the following.

    mkdef -t node -o clstrn04-clstrn10 groups=all,aixnodes mgt=hmc

Note: In some cases you may want to use the xcatsetup command and a cluster configuration file to define the cluster nodes. See the section below for more information on using cluster configuration files.

Create new LPARs using mkvm

To create the new partitions based on the partition profile for node clstrn01 you could run the following command.

    mkvm -V clstn01 -i 4 -n clstrn04-clstrn10

Note: In some cases it is necessary to re-boot the hardware after running the mkvm command. Refer to the man page and documentation listed above for a more complete description.

Using a cluster configuration file.

**This support will be available in xCAT 2.6 and beyond.**

A cluster configuration file contains information that can be used to create initial xCAT cluster definitions for a new cluster. It can include hardware descriptions, node definitions, site information, naming conventions, IP addresses etc.

A cluster configuration file can be used with the xCAT xcatsetup command to "prime" the xCAT database.

The format of a cluster configuration file is described in the man page for the xcatsetup command. (xcatsetup)

Once you have created the configuration file you can run the xcatsetup command as follows:

    xcatsetup > <cluster_config_file>

Discover HMCs/frame/CECs, and define them in xCAT DB

The xCAT lsslp command is used to discover the cluster hardware components such as the HMCs, frames, and CECs.

This command is normally used during the System P hardware discovery phase of the cluster bring-up.

See the lsslp man page for more details. (lsslp)

Also see the following document for a complete description of the hardware discovery and management support. [XCAT_System_p_Hardware_Management_for_HMC_Managed_Systems]
[xCAT_System_p_Hardware_Management_for_DFM_Managed_Systems]

Using the lsslp command

The recommended process is to run the lsslp command to discover the hardware component and create a stanza file. Then pass the stanza file to the mkdef command to create the xCAT definitions.

For example, to gather the HMC information and write it to a stanza file

    lsslp -m -s HMC -z -i 192.168.200.205 > /defs/hmcstanzafile

Note: You need to execute the -m (multicast) flag to reference later supported HMC V7R35x/V7R71 levels.

Review the stanza file and make modifications if necessary.

You will need to include the username and password attributes being used by the target HMC node. Make sure that the HMC host name and ip address is resolvable in the xCAT cluster name resolution (/etc/hosts or DNS).

Create the xCAT definitions using the mkdef command.

    cat /defs/hmcstanzafile | mkdef -z