High Availability Monitors Version A.03.02 Release Notes

Introduction to the NOF API

NOF Indications

Chapter 186

No speciﬁc VCB structure is associated with this indication type.

Instead, when a change to the conﬁguration occurs, SNAplus2 indicates

this change to the application by sending a copy of the completed VCB

from the NOF verb that made the change.

For more information about conﬁguration indications, see

“CONFIG_INDICATION”.

SNA Network File Indications

An application can register to receive information about changes to the

SNA network ﬁle sna.net on the master server. This enables the

application to keep track of changes to this ﬁle that can be made by other

NOF applications or by thecommand-line administration program. To do

this, the application registers as for other indications, specifying

SNA_NET_INDICATION as the requested indication type.

Two VCB structures are associated with this indication type:

• ADD_BACKUP (indicating that a backup server has been added to

the end of the ﬁle)

• DELETE_BACKUP (indicating that an unused backup server has

been removed from the ﬁle)

Registering with a type of SNA_NET_INDICATION will return an

ADD_BACKUP indication when a backup server is added or a

DELETE_BACKUP indication when a server is deleted; the application

does not need to register separately for each of these indications. In each

case, the format of the indication is a copy of the completed VCB from the

NOF verb that made the change.

For more information about SNA network ﬁle indications, see

“SNA_NET_INDICATION”.

NOF Status Indications

SNAplus2 sends a NOF status indication to a registered NOF

application when the application can no longer access its target node or

ﬁle (because the SNAplus2 software on the target computer has been

stopped or because the communications path to this computer has been

lost). If the application is registered to receive indications from the

master conﬁguration ﬁle, this indication is also returned if another

server takes over as master (and therefore the target ﬁle is no longer the

master conﬁguration ﬁle).