Small network setup

I've got:

• 10 windows workstations,
• 1 Linux server,
• 1 Westell 327W modem/router,
• 2 8-ports swithes

Can anyone help me setup network, something like:

[Internet]---[DSL modem/router]---[Linux Server]--[10 Windows workstations]

How far did you get? Is the Linux server connected and running DHCP?

Hi gneeot,

Your Linux server can act as a Firewall , Proxy Server,DHCP server , Windows Sharing Server, any VPN application and port forwading to any of the internal machines.
I think you have 3 options to setup a network
First Option

The Linux Server could be linked to router and from the Linux to the switch and connect all the workstations to the Switch.( Linux server should 2 Lan Card )

Second Option
Connect your Modem / router to the Switch and All the workstations including the Linux server is connected to the Switch

Third Option
Linux itself can act as router so that you can connect the Linux to modem from Linux to Switch and all other workstations to the switch, but network applications are highly susceptile for network attacks So firewall in Linux should be tailored strong and rigid
(Linux server should have 2 Lan card )

The Second option could have a performance drop in
network aspect.

Please let me know if your need further help
Regards

Philix
Jesus Loves you

Thanks Moloko and philix!

Now everything is working like philex's second option, but I want switch it to philix's first or third option. I know how to setup DHCP, samba, apache, but I need some help with routing table, ethernet cards configuration, dns, ssh, firewall. Also I want switch distribution from Fedora Core 3 to Debian.

Hi Gneeot,

Linux can act as router if configured its various parameters,
route -n [ Displays the present details of routing table ]
route add default gw <GW IP Address> will inform the Linux server the external host it has to contact to access internet. The workstations should have its gateway configured to the internal IP address of the linux server. While the <GW IP Address> of the linux server should be the IP provided by your ISP.
Routing & Nat using iptables.
iptables --table nat --append POSTROUTING --out-interface eth0 -j MASQUERADE
iptables --append FORWARD --in-interface eth1 -j ACCEPT
echo 1 > /proc/sys/net/ipv4/ip_forward

Implementing the forwarding Permanently
edit /etc/sysctl.conf
change the net.ipv4.ip_forward = 1

DNS
Do you want this Linux server to be DNS client or server ?
If it is DNS client , you should edit the /etc/resolve.conf
with an entry like
nameserver <DNS IPaddress>
nameserver <DNS Second IPAdress>
DNS server configuration is a long process, Please confirm whether you need the DNS server.

SSH
Please disable the Permit root entry to NO in the sshd_config
Allow only certain users to remote login the SSH, who username is to be little complicated and password to be mixture of alphanumeric characters.
Disable SSH protocol 1 which is a buggy one

Ethernet card can be configured from the ifconfig command or by editing the /etc/sysconfig/networking-scripts/ifcfg-eth0 or ifcfg-eth1
ethtool and mii-tool command gives the link status and Card HW configuration details.

Debian is considered much more stabler and debugged as soon as bugs are informed as lots of Linux lovers are genuniely working on it.

Thanks
Philix

Thanks Philix!
I can't find any good SSH tutorial. Do you know any good one?
How can I disable SSH root entry? SSH protocol 1 ?

Hi Gneeot,

You can find the SSH configuration file under /etc/ssh/sshd_config
Comment the Host Key of the Protocol version 1
Port 22
Protocol 2,1
ListenAddress 0.0.0.0
#ListenAddress ::

# HostKey for protocol version 1
#HostKey /etc/ssh/ssh_host_key# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key

Place the value No for the gievn below entry
PermitRootLogin No

Some link for SSH details
http://www.suso.org/docs/shell/ssh.sdf
http://yolinux.com/TUTORIALS/LinuxTu...urity.html#SSH

Thanks
Philix
Jesus Loves you too