Advice needed for network planning (Firewall, Proxy, DNS, DHCP, SMB, FTP, HTTP, SSH, VPN)

Hello folks!

I am administering a small Network with some Linux boxes as servers and some
Windows based clients.
Now i am thinking about expanding this network with some additional
features.
The purpose of my thread is, to get some advice of you guys on how you would
set this whole thing up, concerning the architecture of the network.

************
For the moment the network looks like this:

1. Linux box with 2 NICs:
- Firewalling between NIC1 (Internet Modem) and NIC2 (LAN)
- DNS
- DHCP

2. Linux box:
- Samba, being the fileserver for the network as well as the PDC and
WINS

3.-7.: Windows clients
************

Now my situation is the following:
- I want to add the following servers:
- FTP
- HTTP
- VPN having access to the windows domain of samba
- Proxy
- I have 2 further PCs at my disposal (ranging from 400MHz to 850MHz)

My question is, on how I should design this network to make most sense in
terms of security and network logic. For instance a question would be if I
can set up the Proxy on the same box as the firewall with it's two NICs, or
if I should move it to a sperate PC having also 2 NICs, and to connect it's
NIC1 to the firewall and it's NIC2 to the LAN.

For instance: Does it make sense to do the following:

DSL----(NIC1)[Linux1 being Firewall](NIC2)----(Nic1)[Linux2 being
Proxy](Nic2)----LAN
on the LAN-Switch connected:
- Linux3 being: HTTP, FTP, DNS, DHCP
- Linux4 being: SMB PDC
- 5 Win clients

or is that much to complicated and overkill?
How would you design the network with the given hardware?
Where would you place the VPN-server which should have acess to the shares
on the SMB-fileserver?
Could I still pass via SSH from internet to the Linux boxes everywhere?

Thanks for any idea
Tom

P.S.:

I would also love to get some hints on the following:

- How to plan the network concerning having a DMZ
- Do you know any good sites with images of network toplologies, for
example: http://www.linuxnetmag.com/de/issue7/m7smoothwall1.html
- Do you know any good out-of-the-box solutions as smoothware, in terms of a
linux-solution that comes with all the tools needed?

Thanx
Tom

Tom wrote:
> Hello folks!
>
> I am administering a small Network with some Linux boxes as servers and
> some Windows based clients.
> Now i am thinking about expanding this network with some additional
> features.
> The purpose of my thread is, to get some advice of you guys on how you
> would set this whole thing up, concerning the architecture of the network.
>
> ************
> For the moment the network looks like this:
>
> 1. Linux box with 2 NICs:
> - Firewalling between NIC1 (Internet Modem) and NIC2 (LAN)
> - DNS
> - DHCP
>
> 2. Linux box:
> - Samba, being the fileserver for the network as well as the PDC and
> WINS
>
> 3.-7.: Windows clients
> ************
>
> Now my situation is the following:
> - I want to add the following servers:
> - FTP
> - HTTP
> - VPN having access to the windows domain of samba
> - Proxy
> - I have 2 further PCs at my disposal (ranging from 400MHz to 850MHz)
>
> My question is, on how I should design this network to make most sense
> in terms of security and network logic. For instance a question would be
> if I can set up the Proxy on the same box as the firewall with it's two
> NICs, or if I should move it to a sperate PC having also 2 NICs, and to
> connect it's NIC1 to the firewall and it's NIC2 to the LAN.
>
> For instance: Does it make sense to do the following:
>
> DSL----(NIC1)[Linux1 being Firewall](NIC2)----(Nic1)[Linux2 being
> Proxy](Nic2)----LAN
> on the LAN-Switch connected:
> - Linux3 being: HTTP, FTP, DNS, DHCP
> - Linux4 being: SMB PDC
> - 5 Win clients
>
> or is that much to complicated and overkill?
> How would you design the network with the given hardware?
> Where would you place the VPN-server which should have acess to the
> shares on the SMB-fileserver?
> Could I still pass via SSH from internet to the Linux boxes everywhere?
>
> Thanks for any idea
> Tom
>

One thing to consider is to use virtual servers, especially a
light-weight virtualisation solution like openvz or linux-vserver. I've
got a machine at the office with openvz - using a simple script, I can
set up a new machine with a minimal debian installation (32-bit or
64-bit - they can be mixed as long as the host is 64-bit) in a couple of
minutes. If I decide I've made a mess of the setup of a particular
service, it's only another couple of minutes to delete the virtual
server and start again.

Keeping things in virtual servers has three big advantages that I see.
One is security - you keep your services separate, and any break-in on
your http server (for example) does not affect your other servers.
Since the openvz guests don't have any valid login users (even root can
be locked - you can enter the guest from the host), they are more
difficult to exploit. Secondly, you have scalability advantages - you
make good use of a modern server PC, and when it starts to get
stretched, you can migrate some of the virtual servers onto a new
machine. The third big advantage I see is that with services running on
separate virtual machine, each virtual machine is kept much simpler and
cleaner, and can be updated separately. If one service requires Python
2.4 or above, and another won't work with anything newer than Python
2.3, you've got no conflicts when they are on different virtual servers.

mvh.,

David

Ok, I have found a very nice turn-key solution. It is a Linux
Routing/Firewalling/Gateway security distribution, supporting the
installation of a DMZ and wireless hotspots.
For anybody who is interested in somethin like that:
http://en.wikipedia.org/wiki/Endian_Firewall

Now what remains is a solution for the remaining services as SMB, FTP, HTTP.
I might set up a openSuSE or Kubuntu for that and administer the services
via Webmin. Alternatively I have found this: http://www.eisfair.org/

Many greetings

tomakos

On Sep 22, 6:15 am, "Tom" <n...@void.void> wrote:
> Hello folks!
>
> I am administering a small Network with some Linux boxes as servers and some
> Windows based clients.
> Now i am thinking about expanding this network with some additional
> features.
> The purpose of my thread is, to get some advice of you guys on how you would
> set this whole thing up, concerning the architecture of the network.
>
> ************
> For the moment the network looks like this:
>
> 1. Linux box with 2 NICs:
> - Firewalling between NIC1 (Internet Modem) and NIC2 (LAN)
> - DNS
> - DHCP
>
> 2. Linux box:
> - Samba, being the fileserver for the network as well as the PDC and
> WINS
>
> 3.-7.: Windows clients
> ************
>
> Now my situation is the following:
> - I want to add the following servers:
> - FTP
> - HTTP
> - VPN having access to the windows domain of samba
> - Proxy
> - I have 2 further PCs at my disposal (ranging from 400MHz to 850MHz)
>
> My question is, on how I should design this network to make most sense in
> terms of security and network logic. For instance a question would be if I
> can set up the Proxy on the same box as the firewall with it's two NICs, or
> if I should move it to a sperate PC having also 2 NICs, and to connect it's
> NIC1 to the firewall and it's NIC2 to the LAN.
>
> For instance: Does it make sense to do the following:
>
> DSL----(NIC1)[Linux1 being Firewall](NIC2)----(Nic1)[Linux2 being
> Proxy](Nic2)----LAN
> on the LAN-Switch connected:
> - Linux3 being: HTTP, FTP, DNS, DHCP
> - Linux4 being: SMB PDC
> - 5 Win clients
>
> or is that much to complicated and overkill?
> How would you design the network with the given hardware?
> Where would you place the VPN-server which should have acess to the shares
> on the SMB-fileserver?
> Could I still pass via SSH from internet to the Linux boxes everywhere?
>
> Thanks for any idea
> Tom

On Linux 1 box set up the additional servers = VPN and Proxy

On Linux 2 box set up the additional servers = ftp http

My setups generally go like this:

1) Install Mandriva on Linux 1 box. Set up shorewall(firewall),
squidproxy(proxy), OpenVPN(VPN).
2) Install Mandriva on Linux 2 box. Set up apache(http), proftp(ftp).

Heck, you could use a third Linux 3 box if you wanted strictly for
SAMBA(Windows anthentication and file sharing).

There have been times when I installed the following servers on a
single Linux box: ftp, http, vpn, firewall, email, proxy, and VoIP
(maximum of 6 simultaneous users). The machine was peacemeal with a
rather small hdd and slow processor with 512RAM. The system supported
roughly 30+ users with no complications or degredation - so long as I
remembered to clear out the logs and squid cache from time-to-time.
It really comes down to what you want to "try out" for learning
purposes...

Your plans are quite commendable - good luck!

Deion "Mule" Christopher

Hello Deion!

> 1) Install Mandriva on Linux 1 box. Set up shorewall(firewall),
> squidproxy(proxy), OpenVPN(VPN).
> 2) Install Mandriva on Linux 2 box. Set up apache(http), proftp(ftp).
>
> Heck, you could use a third Linux 3 box if you wanted strictly for
> SAMBA(Windows anthentication and file sharing).

Thank you for your reply!

I have finished today my installations, and am very happy, that my
configuration actually meets your adviced one almost 100%. So I assume, that
I have done the right thing!
I chose the 3 box config.

Thank you for your advice!

Greetings
tom