Installation and Migration Guide

Appendix E. User-supplied node customization scripts

IBM provides the opportunity to run two different customer-supplied scripts during node installation:

script.cust

This script is run from the PSSP NIM customization script (pssp_script) after the node's AIX and PSSP software have been installed, but before the node has been rebooted. This script is run in a limited environment where not all services are fully configured:

• The installation RAM file system is in place (and not the normal disk file system).
• The node has communications connectivity and routing to its boot/install server only. For example, there is no general connectivity to the control workstation or any internal or external network.
• None of the node's network adapters, with the exception of the installation adapter, are configured and available.
• There is no access to authentication services.

As a result of these restrictions, you should restrict your use of script.cust to function that must be performed prior to the post-installation reboot of the node. An example of appropriate function in script.cust is the installation of an LP that requires a reboot of the node to render it fully functional. See the sample script.cust that follows for additional examples.

Note:

script.cust is also run during the boot of a node that has been set to "customize."

A sample of the script.cust node customization script is located at /usr/lpp/ssp/samples/script.cust.

firstboot.cust

This script is run during the first boot of the node immediately after it has been installed. This script runs in a more "normal" environment where most all services have been fully configured:

• The node's disk file system is in place.
• The node has established its defined communications connections including all routing.
• The css0 adapter has been configured, but is not available.
• The other network adapters configured by PSSP have been started.
• Authentication services are available.

This script is a preferred location for node customization functions that do not require a reboot of the node to become fully enabled.

Note:

firstboot.cust is also run during the boot of a node that has been set to "migrate."

A sample of the firstboot.cust node customization script is located at /usr/lpp/ssp/samples/firstboot.cust.

Note:

Your security environment is not set up during script.cust processing. If you require security function, perform your customization during firstboot.cust processing.

Be aware that the root password is not set if you are installing from a minimal mksysb image. If you want to have the root password set, you can do one of the following:

• Modify the firstboot.cust file by uncommenting the portion of the code to copy the user information from the server to the node.
• If you did not copy the user management files over, then immediately after the node is up without a password, login to the node as root and set the password either through the SMIT panels under Security & Users or with the passwd command.

Name resolution of the control workstation host name is required on the nodes. firstboot.cust shows how to copy /etc/resolv.conf or /etc/hosts, and how to define the node to NIS, if that is being used. If you have created a mksysb image to install on the nodes, and it already has name resolution defined in it, you do not need to do anything additional.

You should use any customizations that were created by using the chdev or chgcss commands, except for those that are already stored in the SDR. For example, customized parameters such as maxuproc, maxmbufs, rpoolsize, spoolsize, and asynchronous I/O should be preserved by using the chdev or chgcss command in these files.