Installation of the router with the operating-system RedHat**-Linux** 9
==> RedHat**-Linux** 9 requieres at least a Pentium I processor and a monitor with a resolution of at least 800 x 600 pixels to run the administration-tools under the GUI.
As I wanted to reuse an (silent and low power-consuming) notebook with a 486 processor as a router for an ADSL-internet-connection, I made also a description how to install a router with RedHat**-Linux** 7.1; for the installation-instruction please follow this link.
The
router handles the connection of the internal network to an
Internet-Service-Provider (ISP).
To achieve the connection a
dial-up-telephone-connection (Plain Old Telephone System / POTS), a
ADSL- or DSL-connection (Asymetric Digital Subscriber Line / Digital
Subscriber Line) or a special model for a cable-tv-provider can be
used.
Additionally this machine can be used as a telefacs-server for the workstations on the internal network (intranet).
As the workload is not pretty high on this machine, an PC with a Pentium I with 133 Mhz, 64 Mbyte of RAM and 2,5 Mbyte disk-capacity is sufficient.
All following instructions are for installing RedHat**-Linux** version 9.
Shortly
after the boot-process from diskette or CD beginns, a selection for
text-based or graphical-installation can be done.
As the router
needs neither a mouse nor an expensive video-graphic-adapter, the
following installation-instructions are for text-mode.
Please select the appropriate values according to your configuration.
This
computer is the 'security guard' which has to prevent attacks of all
kind from the public internet to reach the private intranet.
To
avoid the installation of packets causing security holes and to waste
capacity with not used functions, Linux** will be installed as Custom
System..
Select Manually partition with Disk Druid
|
/boot |
100 MByte |
Format partition as: ext3 |
|
Swap |
250 MByte |
Format partition as: swap |
|
/ |
Rest of the disk |
Format partition as: ext3 |
Do not change the default values.
This option is
not shown if the NIC (network interface card) is not detected during
the installation-process.
In that case the instruction for
'Configure the Network Interface Card'
apply after finishing the stardard-installation.
Use
bootp/dhcp: No (do not check)
Activate
on boot: Yes (check)
IP
Adress: 192.168.0.254
Netmask:
255.255.255.0
Default gateway (IP): (leave blank)
Primary
nameserver, Secondary nameserver and Tertiary nameserver:
The
TCP/IP-Addresses of the Domain-Name-Servers (DNS) are provided by
the used Internet-Service-Provider (ISP) .
Here is a list of some
Austrian ISP:
A-ON: 195.3.96.67, 195.3.96.68
UTA:
195.70.224.61, 195.70.224.62
If
there is already a second NIC istalled (for DSL, ADSL or cable-modem
connection), the previous screen appears again. As it depends which
kind of connection is used to connect to an ISP, the instructions
will follow later.
So far leave the values unchanged.
Hostname: router
No firewall (check)
Do not change all other values.
N.B.: The protection of the internal network is done with a script. The description follows under Linux - Firewall and Masquerading .
English(USA) (check)
N.B.: If necessary more than one language can be chosen.
Hardware clock set to GMT: Yes (check)
Europe/Vienna (check) - or wherever the server is located ;-)
Choose a Root Password (for Administrator-functions).
N.B.: Passwords are case
sensitive; so check if 'caps-lock' is enabled when you enter the
Root Password.
My recomendation is, to use only lower case
character for passwords.
Do not change the values.
The following list comprises only those packages which have to be installed.
Printing Support
Text-based Internet
Depending on utilities to
be installed several packages must be selected individually.
After
checking 'Select individual packages' and clicking on the 'Next'
button, groups of packages will be displayed.
According to the
intended services and application-programs the following packages
must be selected (checked):
|
System Environment/Base - iptables-ipv6 |
|
|
SAMBA-Server
|
Applications/System - samba-swat |
It might happen, that further packages habe to be installed to fulfill dependencies. Please confirm the suggestions of the installer.
To create a boot disk is
not absolutely necessary as there are now tools available to recover
from a disk that is no longer bootable.
And my experience told
me, that the Boot Disk is lost when you need it ;-).
So I leave
it up to you to create a Boot Disk or not.
My decision was:
No, I
do not want to create a boot diskette: check.
Under certain
circumstances the TCP-/IP-address defined during
standard-installation is not put to the configuration-file
/etc/hosts.
If you do not find a line starting with the chosen TCP/IP-address
(192.168.0.254 in this example), please insert the missing line.
Here
is an example how the configuration-file /etc/hosts
should look like :
#
Do not remove the following line, or various programs
# that
requiere network functionality will
fail
127.0.0.1 localhost.localdomain localhost
192.168.0.254
router.g2t.office.at router
The above example aasumes, that the TCP/IP--Hostname as described under NetBIOS- and TCP/IP-Setup of a workstation was router.g2t.office.at .
The
configuration of the NICs is highly dependant on the manufacturer and
the type of the NIC.
If there are 2 NICs installed (1 for the
internal network, 1 for the connection to an ISP over ADSL, DSL or
cable-modem), then it is strongly recommended to use different types
of NIC. This simplifies the identification which NIC should be
connected to which cable.
Newer network-interface-cards (NIC) are detected during the standard-installation. If this is so, you will already find the configuration (symbolic i/o and driver) in the file /etc/modules.conf; an example is shown here:
alias
eth0 3c59x
alias eth1 ne
If the card was not
detected during the installation, driver and - if the card has not a
plug-and-play capability - the i/o-parameters must be assigned
manually by editing the file /etc/modules.conf.
If other lines are already exist in this file they must not be
deleted.
A detailed description for a lot of NICs can be found in the Linux Ethernet-HOWTO.
Special procedure for notebooks (pc-card).
NIC-function is available
after starting pc-card-services.
For this reason, NICs can
not be detected during installation but are available after a restart
of Linux.
If the
network-interface-cards (NIC) were detected during the
standard-installation there was also a request to enter the
network-parameter.
The parameters can be verified in the file
/etc/sysconfig/network-scripts/ifcfg-eth0
or /etc/sysconfig/network-scripts/ifcfg-eth1
respectively.
As
the connection to the ISP is dependant on the parameters provided by
the ISP, the following instruction comprise only the connection to
the internal network.
The following instructions assume that the
connection to the internal network is done via eth0
with the TCP/IP-address 192.168.0.254.
The file /etc/sysconfig/network-scripts/ifcfg-eth0 should look like this:
DEVICE=eth0
BOOTPROTO=static
BROADCAST=192.168.0.255
IPADDR=192.168.0.254
NETMASK=255.255.255.0
NETWORK=192.168.0.0
ONBOOT=yes
If the configuration is as planned can be verified after a restart with the command:
ifconfig eth0
Checking for a correct installation of the network:
If the drivers where
installed correctly is shown during startup in the step
'Bringing up interface eth0' ([OK])
or
can be checked
after a restart with the following command:.
modprobe eth0
dmesg |
tail
There are shown the last
lines of the log.
Unfortunately each driver logs its special
message; but if the Hardware-ID of the Network-Interface-Card is
shown (e.g. 0060 97 72 b0 93) it is a good sign.
Then correct setup of the own TCP/IP-Address can be checked with the following command.
ping 192.168.0.254 (where the TCP/IP-Address of the just installed machine must be used - if you did not take the one from the examples)
shows the result:
PING 192.168.0.254
(192.168.0.254) from 192.168.0.254 : 56(84) bytes of data
64 bytes
from 192.168.0.254:
icmp_seq=0 ttl=255 time=2.0 ms
64 bytes from 192.168.0.254:
icmp_seq=1 ttl=255 time=1.3 ms
64 bytes from 192.168.0.254:
icmp_seq=2 ttl=255 time=1.1 ms
64 bytes from 192.168.0.254:
icmp_seq=3 ttl=255 time=0.9 ms
The 'Pinging' can be interrupted with the key-combination CTRL-C and thereafter a statistic is shown (example):
--- 192.168.0.254
ping statistics ---
4 packets transmitted, 4 packets received, 0%
packet loss
round-trip min/avg/max = 0.9/1.2/2.0 ms
If
the computer is already connected to a local area network (LAN),
then the correct connection can be tested by 'Pinging' a known
TCP/IP-Address of another computer connected to the LAN.
ping 192.168.0.1 (where the Operatins-System of the pinged computer must be running - of course)
shows the result:
PING 192.168.0.1
(192.168.0.1)
from 192.168.0.254 : 56(84) bytes of data
64 bytes from
192.168.0.1:
icmp_seq=0 ttl=255 time=3.2 ms
64 bytes from 192.168.0.1:
icmp_seq=1 ttl=255 time=1.4 ms
64 bytes from 192.168.0.1:
icmp_seq=2 ttl=255 time=1.3 ms
64 bytes from 192.168.0.1:
icmp_seq=3 ttl=255 time=1.3 ms
64 bytes from 192.168.0.1:
icmp_seq=4 ttl=255 time=1.3 ms
The 'Pinging' can be interrupted with the key-combination CTRL-C and thereafter a statistic is shown (example):
---
192.168.0.1 ping statistics ---
5 packets transmitted, 5 packets
received, 0% packet loss
round-trip min/avg/max = 1.3/1.7/3.2 ms
If there is a second NIC installed (for connection to a ADSL-, DSL- or cable-modem) the connection will be tested during the setup of the respective protocol. This setup is described under 'Service-applications for the router'.
Further
steps of installation:
Further steps of installation of a Router with RedHat**-Linux** 9 are lined out in the following documents:
Linux-workstation
- file-structure and users.
This
is not absolutely neccessary as the programs to set up a
dial-up-connection or a tunneling-protocol are small enough to be
transferred with a diskette.
But together with Mounting
of directories on a remote computer this
allows a later logon to the router to transfer downloaded programs
to this machine.
This step has to be done later if you installed
the fax-server hylafax and users on workstations should be able to
send faxes out from this machine.