TCP/IPv6 Migration Guide

Migration Considerations
HP NonStop TCP/IPv6 Migration Guide—524524-004
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Fault-Tolerant Behavior
An application programmatic interface (API) difference in NonStop TCP/IPv6 involves
the error message returned for unresolved host names. TCP/IPv6 uses the
getaddrinfo() routine to resolve the host name instead of gethostbyname()
which returned the error "unknown host." The getaddrinfo() routine returns the
following error when a host name cannot be resolved: "Name does not resolve to
supplied parameters."
Fault-Tolerant Behavior
Most fault-tolerant behavior differences relate to TCP6SAM. Those differences are
described in Section 2, The New Socket Provider. Two additional considerations
concerning fault-tolerant behavior are:
•
Differences in failure information reporting
As in NonStop TCP/IP, in NonStop TCP/IPv6, if the TCP6MON or TCP6SAM
process detects a failure condition, TCP6MON or TCP6SAM dials out the failure
information to the Global Customer Support Center (GCSC) using HP Tandem
Failure Data System (TFDS). However, if the failure is detected in the TCP/IP
library within the application context, the TCP/IP library cannot call TFDS to notify
GCSC.
•
Upon failure of any NonStop TCP/IPv6 processor or TCP6MON process,
applications connected to Guardian TCP sockets which were on that failed
processor or process do not have their TCP connection reset. This behavior is
unlike NonStop TCP/IP.
•
For fault-tolerant socket applications, if the application primary process fails, the
backup application receives an ECONNRESET error upon its first socket request
after takeover.
Firewall Considerations
When considering migration to NonStop TCP/IPv6, ensure that your firewall products
support gratuitous ARP packets.
Management Interfaces
This subsection describes differences in the management interfaces between NonStop
TCP/IP and NonStop TCP/IPv6.
Subsystem Name and ID
The subsystem ID for NonStop TCP/IP is ZTCI. The name for NonStop TCP/IPv6 is
ZTC6.
TCPIPV6 replaces TCPIP as the subsystem name and should be used when
requesting SCF help.