HP-UX HB v13.00 Ch-09 - Networking Basics

HP-UX Handbook – Rev 13.00 Page 14 (of 27)
Chapter 09 Network Basics
October 29, 2013
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lan0 UP 0x00306EF30764 igelan 1000Base-T
lan1 UP 0x001A4B066052 iether 1000Base-T
lan2 UP 0x001A4B066053 iether 1000Base-T
lan900 DOWN 0x000000000000 hp_apa hp_apa
These commands can also be used to change the network settings on a running system. But
please keep in mind that some programs/applications may have problems changing the network
environment during runtime.
To check your basic installation or to test settings, it helps to configure a new interface manually.
Please check the examples (following later in this chapter) on how to use those commands.
Sometimes it is required to change the default network behavior of the HP-UX kernel to interact
with specific network environments. This can be done with the following commands:
ndd (HP-UX 11.X)
nettune (HP-UX 10.X)
These commands allow you to change the kernel settings without a reboot. To make the changes
permanent (surviving a reboot) on HP-UX 11.X we have to write the appropriate entries into the
file.
/etc/rc.config.d/nddconf
Refer to the man page ndd and/or check:
http://teams3.sharepoint.hp.com/teams/esssupport/InsideESSSupport/InsideWTEC/NETUX-
XPORT/Pages/NDD%20parameters/nddparams.aspx, (HP internal).
Installation Hints
Here are some descriptions and installation hints to avoid known problems.
Special HP-UX Feature: Usage of RFC 1122 – Subnet Issue
According to RFC 1122 not all possible subnet address combinations are allowed. The HP-UX
operating system tests those conditions upon activation of the IP address with ifconfig. You will
see ioctl error messages, if this problem occurs. Since newer RFCs impose fewer restrictions,
you can turn off this test on HP-UX 11.X with the following ndd command (and corresponding
ndd.conf entries):
# ndd -set /dev/ip ip_check_subnet_addr 0
Duplex Modi
Most of the currently used network interfaces and switches have configurable speed and duplex
settings. Even if all involved parties use algorithms to check and set the best values for speed
(via auto-sensing) and duplex (via auto-negotiation) automatically, we have often seen problems
with auto-negotiation in the past. Please do not forget the following rules:
A network interface and the switch port to which it is connected must use the same settings,
either using AUTO or using the same specific value