HP Integrity NonStop H-Series - Manual (Page 21)

Figure 3 Post Master instances for different TCP/IP providers
IP-CIP TCPIPv6
Post Master Instances
Accessible
NOTE: HP recommends IP-CIP for better scalability.
NSASJ Server for Scalability
A server, in an NSASJ configuration has only one definition but multiple instances of the same
server. The server is configured as a TS/MP serverclass and all the instances of the server share
the same configuration and set of file system resources.
In cases where session beans are serviced, Post Master acts as a Pathsend client and the NSASJ
sever acts as a TS/MP serverclass. In such cases, the NSASJ Server inherits the scalability
functionalities and features of a TS/MP serverclass.
In cases where Message Driven Beans are serviced, NSASJ uses a resource adapter to connect
to the NSMQ message broker. In such cases, NSASJ Server acts as a plain message consumer
and connects to the NSMQ broker over a TCP connection. Each instance of the NSASJ serverclass
now acts as a plain message consumer. However, the system does not guarantee that the messages
in the broker are equally distributed across the instances of the NSASJ serverclass.
If new instances of NSASJ are started, it ensures that there are more message consumers. Thus,
this increases the overall system capacity to consume messages.
Scalability 21