to one with the same model string72). The following happens, depending on what value you set it to:

0 – A yes/no question is asked: Do you wish to cancel the non-interactive installation in order to respond to the warnings above?. There is no timeout associated with this question; Ignite-UX waits indefinitely for a response.

1 – This message appears: Continuing despite above warnings because INST_ALLOW_WARNINGS=1. The installation/recovery proceeds regardless.

>1 – This message appears: Press <Return/Enter> within <num> seconds to

cancel batch-mode installation: . You have that number of seconds to press Return or Enter to cancel the non-interactive session to enter the user interface.

∙INST_ENABLE_NETWORK—this environment variable is useful when you have created media from which to boot a system, but you need the installation process to start networking (for example, one of the scripts used needs to contact another host). For example, setting this variable to 1 does this:

env_vars += "INST_ENABLE_NETWORK=1"

Unless use_dhcp has been set to FALSE, the system attempts to contact a DHCP server at that point.

∙LOADFILE_RETRY_COUNT—this has the following description in the instl_adm(4) manpage:

This can be used change the default number of times that the internal loadfile command will retry a failed attempt to retrieve data from the server or media. Usually this retry mechanism is used to overcome tftp transfer problems. The default value is 5.

As an alternative, you can use the _hp_tftp_cmds to change the re-transmission and timeout values when tftp is actually used.

Managing configurations with unifdef

You may find when writing configuration files that many of them tend to end up looking the same. There are at least two programs that you can use in conjunction with configuration files to make similar files more maintainable.

The program you can use at is unifdef (The second program is m4, but how to use m4 is not discussed.)

The following example looks at the configuration files discussed in "Configuration examples – Part B". Suppose you have one very long configuration file that you want to save into an LIF, but over time you have finally exceeded the 8KB limit on configuration data so you have a configuration file that looks like the following:

72When you set INST_ALLOW_WARNINGS to a non-zero value and you are performing a non-interactive recovery (especially cloning to the same hardware) or installation, it is possible that the warnings can be extremely important. For example, if you are cloning between systems of the same model but the boot disks are at different hardware paths (especially on a Fibre Channel attached array) and you do not interrupt the boot process in time, the installation/recovery session may have overwritten production data or data belonging to a different system.

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