• Choose a category
• All
• Classic-Fiction

Table 13.20 PPP-related files on HP-UX

Despite their quality, the man pages for these configuration files suffer from a bizarre and unaccountable lapse of naming: the name of each man page has ppp. prefixed to the name of the file it describes. For example, the command man Systems fails, but man ppp.Systems shows a nicely detailed description of the format of the Systems file, including several examples.

The /etc/ppp directory also contains sample files for each configuration file. Here is a snippet from the Systems.ex file; these lines were preceded by hundreds of lines of comments that seemed to include most of the ppp.Systems man page:

# Examples of entries that we use at Morning Star Technologies

#

#roughy Any ACU 19200-PEP 5551212 ogin:--ogin: Premora ssword: \qkjLJHIuD

#manatee Any ACU 38400 5552468 ogin:--ogin: Premora ssword: \qd7DW3KlZ

The directory /etc/ppp/examples contains some specifics regarding terminal servers from various manufacturers.

To run PPP on HP-UX, you must populate the UUCP files with information about your modems and the systems you want to talk to, including the remote login and password that are needed to connect to the terminal server at the other end of your phone line. You must then create and edit the /etc/ppp/Autostart script to start the pppd daemon with the appropriate arguments for your connection. The sample script Autostart.ex is well commented and includes examples. At boot time, one of the files in /sbin/rc2.d will call Autostart automatically.

Networking quirks for HP-UX

HP-UX is testy about hostnames longer than 8 characters. You can use longer names, but you must specify a UUCP-style nodename in /etc/rc.sysconfig.d/NODENAME that is 8 characters or less.

13.14 NETWORK CONFIGURATION FOR RED HAT

Red Hat Linux keeps most network configuration files in the /etc/sysconfig and /etc/sysconfig/network-scripts directories. It supports DHCP, PPP, and IP filtering. The networking stack also includes support for SACKs—selective acknowledgments—which sometimes improve TCP performance on congested links.

Basic network configuration for Red Hat

A Red Hat machine’s hostname is set in the file /etc/sysconfig/network, which also contains lines that specify the machine’s DNS domain and default gateway. For example, here is a network file for a host that has a single Ethernet interface and should not forward IP packets:

NETWORKING=yes

FORWARD_IPV4=false

HOSTNAME=redhat.xor.com

DOMAINNAME=xor.com

GATEWAY=192.108.21.254

GATEWAYDEV=eth0

When you set the hostname in the network file, you should also update the contents of the /etc/hostname file. The hostname file is currently only used for backward compatibility, however.

Interface-specific data is stored in /etc/sysconfig/network-scripts/ifcfg-ifname, where ifname is the name of the network interface. These configuration files let you set the IP address, netmask, network, and broadcast address for each interface. They also include a line that specifies whether the interface should be configured “up” at boot time, which is useful on a laptop or mobile computer.

Typically, files for an Ethernet interface (eth0) and for the loopback interface (lo) are present. For example,

DEVICE=eth0

IPADDR=192.108.21.73

NETMASK=255.255.255.0

NETWORK=192.108.21.0

BROADCAST=192.108.21.255

ONBOOT=yes

and

DEVICE=lo

IPADDR=127.0.0.1

NETMASK=255.0.0.0

NETWORK=127.0.0.0

BROADCAST=127.255.255.255

ONBOOT=yes

are the ifcfg-eth0 and ifcfg-lo0 files for the machine redhat.xor.com described in the network file earlier in this section.

Red Hat provides a couple of handy scripts that facilitate interface management. /sbin/ifup and /sbin/ifdown take the name of a network interface as an argument and bring the specified interface up or down. After changing network information in any of the /etc/sysconfig directories, be sure to do /sbin/ifdown ifname followed by /sbin/ifup ifname. Better yet, reboot the system