HP-UX SNAplus2 R7 NOF Programmer's Guide

Introduction to the NOF API

NOF Indications

• QUERY_NODE

To ﬁnd out which servers are acting as the master conﬁguration ﬁle server and backup master servers, use the

following verb:

• QUERY_SNA_NET

To add new backup master servers to the list or to remove existing servers from the list so that they can no longer

act as master servers, use the following verbs:

• ADD_BACKUP, DELETE_BACKUP

1.5.19 Managing Conﬁguration File Header Information

To add a descriptive comment string to the domain conﬁguration ﬁle, use the following verb:

• DEFINE_DOMAIN_CONFIG_FILE

To obtain information about the SNAplus2 version number for which the domain conﬁguration ﬁle was created or

about the comment string stored in it, use the following verb:

• QUERY_DOMAIN_CONFIG_FILE

There are no corresponding verbs for the node conﬁguration ﬁle because the header information in the node

conﬁguration ﬁle is for SNAplus2 internal use only; do not attempt to modify it.

1.5.20 Managing HP-UX Resource Usage

To set a limit on the amount of kernel memory that SNAplus2 can use for internal data structures or to specify the

maximum amount of memory available for STREAMS buffers, use the following verbs:

• SET_KERNEL_MEMORY_LIMIT, SET_BUFFER_AVAILABILITY

To obtain information about the current limits and usage, use the following verbs:

• QUERY_KERNEL_MEMORY_LIMIT, QUERY_BUFFER_AVAILABILITY

1.6 NOF Indications

A NOF application can use the REGISTER_INDICATION_SINK verb to request information about changes to

the SNAplus2 conﬁguration or to the status of its resources. SNAplus2 then sends an indication message to the

application each time a change occurs.

For a complete list of indications that an application can request, see Chapter 4,

NOF Indications.

Except for CONFIG_INDICATION, NOF_STATUS_INDICATION, and SNA_NET_INDICATION, each indication

is returned when a resource of the speciﬁed type changes its status. For example, if the application registers for

DLC indications, SNAplus2 sends a DLC_INDICATION message to the application each time a DLC becomes

active or inactive.

An indication returns summary information about the change that has occurred. If necessary, the application can

then issue the appropriate QUERY_* verb to obtain more detailed information.

If the local node is short of resources, it can temporarily suppress indications and not send them to applications.

When the resource shortage condition clears, and the local node subsequently generates an indication of a type

that it has previously suppressed, it then sets a parameter on the indication to inform the application that one or

more previous indications of this type have been lost. The application should then issue QUERY_* verbs for the

appropriate resource type to determine the current state of resources.