Node and Host Name Sizes on HP-UX: Using the Expanded Capabilities of HP-UX

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Summary
HP has provided expanded node and host names in response to the needs expressed by customers.
This feature increases the maximum node and host name lengths from 8 bytes and 64 bytes,
respectively, to 255 (plus terminating null) for both.
Because of the interface changes this involves, an interface version (or level) has been introduced that
includes expansions for the node name and host name-related APIs. The associated system
commands and utilities have been updated to use the expanded APIs themselves.
However, longer names must be used with extreme caution. Programs that are not rebuilt to
accommodate the expanded name interfaces will truncate the names or receive an error. This can
cause programs to exhibit ambiguous output or incorrect behavior (including unexpected and
undetermined aborts). In order to avoid these problems, the default system and product
configuration settings limit names to the original, compatible, maximums. The system administrator
must explicitly enable the expanded name capability through a kernel tunable.
This paper has described how to activate the capability, limitations of specific HP products, how
software developers can determine whether their products have dependencies on node or host name
sizes, and how to enhance the programs to accommodate long names