TCP/IP (Parallel Library) Configuration and Management Manual

Introduction
HP NonStop TCP/IP (Parallel Library) Configuration and Management Manual—522271-006
2-9
Architectural Overview
selected by the application. In this case, static routes need to be added to both
subnets of the pair if both LIFs are to participate.
•
Ethernet failover may not function when directly connected to a firewall that uses
Ethernet address (MAC) to IP address filtering. This problem can be overcome by
adding a router between the LIFs and the firewall.
•
When configuring multiple shared-IP failover pairs, the reserved IP address cannot
be shared between pairs.
•
If you use IP alias addresses, they must be added to both SUBNETs of a failover
pair to preserve their availability during a failure. Also, alias IP addresses can only
be shared between SUBNETs configured as a failover pair.
•
When a pair of LIFs has been configured for Ethernet failover, separating them for
use on distinct subnets requires a manual deletion of the SUBNET objects to
disassociate them. The LIFs can then be used in the non-failover configuration
(that is, one LIF per subnet).
To configure your Parallel Library TCP/IP environment for Ethernet failover, you must
use both the ADD SUBNET and ALTER SUBNET commands. See the ADD SUBNET
Command for TCPMAN on page 5-21 and ALTER SUBNET Command for TCPMAN
on page 5-30.
Architectural Overview
These are the product modules for Parallel Library TCP/IP:
•
TCP/IP Manager Process (TCPMAN)
•
TCP/IP Monitor Process (TCPMON)
•
TCP/IP Socket Access Method (TCPSAM)
•
TCP/IP Shared Runtime Library (SRL) (TCPLIB)
•
TCP/IP Ptrace Product Module
•
TCP/IP SCF Product Module
For product numbers, see the TCP/IP (Parallel Library) Migration Guide.
Some components of the Parallel Library TCP/IP subsystem are not involved in the
data path; they exist for management purposes only. These components include the
TCPMAN, TCPSAM, SCF, and PTrace product modules. Figure 2-3 on page 2-10
shows the data paths in Parallel Library TCP/IP and compares them to the data paths
in conventional TCP/IP.