Ubuntu Security :: Firewall Without Router - No DHCP
Feb 15, 2011I want to have a firewall that is connected to my modem and router and have it function as just a firewall no dhcp no routing is that possible?
View 3 RepliesI want to have a firewall that is connected to my modem and router and have it function as just a firewall no dhcp no routing is that possible?
View 3 RepliesIn an effort to learn more about firewalls and iptables I have left behind gui set-up tools and have setup a firewall using iptables that logs to its own file. The firewall is as follows:
Code:
*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [0:0]
:TCP - [0:0]
[Code]...
I get all my traffic from my router, as this computer seldom moves. So is there a use for a firewall?I am not sure, because when I scan my IP address with nmap, no matter what the changes I make in the firewall, it is always the same scan...cannot fingerprint OS...and all closed ports.The all closed ports thing only changes when i torrent, then i get a wide open port.
View 14 Replies View RelatedI am trying to setup a firewall using Centos 5.5. The machine has 2 NICs, one connecting to the ISP/Modem and the other connected to a DIR-655 wireless router. The nic is connecting to the internet port on the router.
I do not want DHCP on the Firewall machine but on the wireless router.
[ISP/Modem]<--->[machine eth0]<--->[machine eht1]<--->[DIR-655 internet port]
IP from ISP Dynamic 192.168.1.1 192.168.1.2
IP's on the DIR-655 LAN will be 124.168.0.0/24 network lets say.
I have setup routes on the eth0 192.168.0.0/24 and 124.168.0.0/24
and added 124.168.0.0/24 to eth1.
I can ping eth0 and eth1 but cannot ping 192.168.1.2.
this setup is not actually connected to the internet so I disabled iptables to try testing the ping and still no good.
There are routers with firewalls which you cannot configure - you just use those routers and get some protection from Internet attacks. Is it possible to configure iptables on GNU/Linux machine so that you'll get better protection than the protection you get from those kind of routers?
View 4 Replies View RelatedWithin the documentation of example OpenVPN setups there is a setup that shows an OpenVPN Server with two network interfaces. One interfaces is plugged into the public internet network and the second interface is plugged into the private network.
Normally I assume that it would be best to place the OpenVPN system inside the network behind the router and firewall and open only the ports needed on the router to allow access to the OpenVPN system. All other router ports would be closed. This is the first example they show. To see what I am talking about see page(s) 6-7 here -> [URL]
If one were to use the two interface public facing setup, when would that setup best be justified? I guess if you didn't want to open any ports on the router/firewall then this could be justified but then you have to lock down this public system individually instead of having it protected by the network firewall.
I would like to know the blocking methode In a Firewall or a Router.whether i will be done by Protocol wise, ho? or it will done through Host wise, How ?
View 2 Replies View RelatedCan we use iptables as firewall instead of Juniper firewall
View 2 Replies View RelatedI want to setup a router with firewall on ubuntu box that will connect windows pcs one serving as outside source and one serving as inside target.
View 2 Replies View RelatedMy isp gave me a router which has wifi.
I added an ubuntu box acting as a router, so the layout is this:
Now, the lan has 192.168.2.0 subnet, and the external interface of the router is in the 192.168.1.0 subnet
So the problem is that the wifi assigns 192.168.1.0 ip's which doesnt belong or get filtered through my router/firewall...
I have seen tutorials on setting up a secured firewall/router/gateway using ubuntu server as the platform. However, I am wondering if anyone has had experience with using an aircard (wireless broadband card via usb) to set up a router.
Which card do you recommend? Any precautions? Any specific code already written to automatically recognize mobile broadband cards and restart the connection if it goes stale?
I have linux server setup on a network with 2 interfaces. One (eth0) is connected to the regular network and the other (eth1) has a DHCP server and transparent web cache listening on it. The machines connected on the eth1 side are on a different subnet and the linux server is there gateway. Untrusted machines are introduced to this network to keep them isolated.
This isolation works well, too well. There are a small set of resources on the regular network I would like to make available to machines on untrustworthy network. I think I need to use iptables but alas I've had no luck in piecing together the command I need (in one case looking myself out and having to physically reset the machine).
post the "perfect" tutorial for setting up a router and firewall for Ubuntu 10.10 Server 64-bit? I'm kind of a n00b when it comes to Linux, so I get really confused with some things, I have seen things on the ubuntu wiki about this... but it really confuses me =
I'm trying to setup my ubuntu sys as a router and firewall... Internet -> Ubuntu (Router) -> Switch (no DHCP on it) -> Computers I've already setup bind and dhcp3 and got those working perfectly... I've also setup Squid3 and Dansguardian for content filtering (blocking ads and such) and got them working too... I want to set it all up to be transparent, and allow the system itself to function as a powerful firewall router, giving absolutely NO issues to client computers connected, and no speed reduction at all.... I want to setup the firewall to allow all outgoing connections, but block everything incoming (stealth the network)... Forcing all http/s traffic to pass through dansguardian, then to squid...
But am very confused on how to pull this off... The system is running Ubuntu 10.10 Server 64-bit, with 4 GB of RAM, 320 GB SSD, and two 1Gb NIC cards... Sorry if I'm not very clear, I do speak english perfectly, but just kinda new to the "Linux world", I was using SONICWALL but that's getting a little too costly to my network and wanna do a free alternative... Something completely CUSTOM, not using some network security distro.
So what I want to do is setup a gateway(or router, idk what Ubuntu refers to it as.). So my set up would be Modem>Server>Switch>Router. I know that I need to set up it up as a DHCP server as well. I would also like to setup it up as a firewall too. I already have two Gbit cards that are already configured. So how do I do this? I already tried one tutorial, but it was old and was for Debian. I also installed ebox, but I couldnt figure that out either.
View 1 Replies View RelatedI want to do is setup a gateway(or router, idk what Ubuntu refers to it as.). So my set up would be Modem>Server>Switch>Router. I know that I need to set up it up as a DHCP server as well. I would also like to setup it up as a firewall too. I already have two Gbit cards that are already configured. So how do I do this? I already tried one tutorial, but it was old and was for Debian. I also installed ebox, but I couldnt figure that out either.
View 2 Replies View RelatedI am establishing ad hoc connection between two PCs
1. LAPTOP: WIFI adapter OS: Ubuntu 9.10 Connection name: trial Address: 192.168.1.36 Subnet: 255.255.255.0 Gateway: 192.168.1.1
2. PC with wired Internet connection + WIFI adapter OS: Windows XP Connection name and parameters same as above except ip: 192.168.1.40
I can see trial is getting connected with excellent strength. When i try to run an Internet on Ubuntu it is not working. Firewall is not active and Router is enabled.
My ISP provides my internet via DHCP. I have a home wireless router to provide internet access, wired for my desktop machine and wireless for my laptop. My question is: Is it possible to configure the router (the Access Point) to provide internet to the desktop and the laptop via static IP? Currently I have managed to configure the internet to them via DHCP and it works. I am just curious to know whether it is possible to provide the internet for them by static IPs, given that the internet that actually goes into the Access Point (the wireless home router), is DHCP.I fiddled with this a lot yesterday, but I only managed to get a working configuraton by DHCP for both the desktop and the laptop. If I supply them with static IPs, I can only ping the Access Point, but not beyond it. So does it at all make any sense to try to configure them by static IPs, i.e. is that virtually possible?
View 10 Replies View Relatedswitched recently to 11.2 and it works fine for me as workstation I want to set up a router separating a part of the network and also acting as a firewall/proxy... Configured 2 Ethernet Interfaces, checked Ip forwarding in Yast but it does not forward the packets from the "internal" to the "external" network. Hovewer after I set up my router as default for machines on internal network I can ping the external interface but no adress on external network (particularly the one of the default router) !!! From the router I can reach both networks and the net via default gateway on external. Tried to:
a) switch firewall completely off
b) iptables -P FORWARD ACCEPT
c) masquarading internal adresses to the external network
my interfaces configuration looks like:
eth0 Link encap:Ethernet HWaddr 00:13:D4:E3:A2:7B
inet addr:192.168.1.34 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::213:d4ff:fee3:a27b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
[Code].....
Fresh install of 10.04.1 server; installs seamlessly; finds network no problem.
However, establishing static connection is driving me batty. Will not take. I've reconfigured "interfaces" file several times. My fingers are numb ifdown-ing and ifup-ing and /etc/init.d/network restart-ing.
I have two files in /etc/network ... interfaces and interfaces~ (one static and the other dhcp). I can switch them in and out of play. The dhcp works and pings out like a champ. static is dead, just dead. Cannot ping router ... nothing.
My router is crap. If I use DHCP it sets all the computers DNS to itself and all DNS requests get cached in the router. It even starts to loose some DNS request if to many are made at once. On my windows PCs this isnt a problem I just set DNS to google's public DNS servers (8.8.8.8 & 8.8.4.4) and bypass my router and ISP alltogether but when i go to pref>network_connections i have to either set DHCP or manual, there is no option to set DHCP with custom DNS.
I'm sure there must be a way to do this in terminal, can someone tell me how?
I'm using ubuntu 10.10.
when I change the hostname on my Ubuntu server, the DHCP clients table in my router is dropped.I'm running 32-bit Ubuntu Server 10.10. My router is a Linksys WRT54GL with firmware version 4.30.15. I'm changing the hostname by modifying /etc/hosts and /etc/hostname. I've also tried changing the hostname using the Linux hostname command in a terminal, but this does not seem to behave correctly according to the manpages (it does not actually change the hostname, or update either of the aforementioned files).
I've also tried using a different router - a Linksys BEFSR41 - but the DHCP table is still dropped when I change the hostname on my server (although this router is not all that different from my other one).
I installed PCLOS 2010.07 into my laptop and dual booting with windows vista. Now I got a weird problem that is when I connected linux to my wifi router, it cannot obtain IP! (it still work correctly in windows, problem just with linux) I had to manually set ip and that worked. Now i wonder what is happening, because I didn't see this problem with PCLOS 2009 borrowed from my friend few months ago.
View 4 Replies View RelatedI am trying to set up a DUAL WAN Load balancer on linux. All i want is just the dual wan loadbalancing and nothing else not even the firewall service. Also what would be the ideal configration for that system
View 2 Replies View RelatedI have a Suse11 box with 2 network cards:
I have squid as a proxy on the Suse box, and with the default firewall I have to enable masquerading to allow clients on the eth3:1-3 to send and receive mail through the Suse box. I found the Suse firewall completely inadequate (all P2P software/connections are allowed once you enable masquerading) and had to install ConfigServer Security & Firewall. In die configuration of csf I could get my way around getting smtp to work for the eth3:1-3 clients, but pop3 connections does not go through the box. I know I need to allow port 110 and 995 to masquerade of NAT (or something) and then the same for port 22
could set up a firewall on my linux machine? I have is to connect my router wired to the linux machine and then from the linux machine to my main computer, and obviously routing the internet connection through the linux box as a firewall. I use a Netgear DG834G router
View 9 Replies View RelatedI am looking for a solution for our LAN traffic monitoring and would like to use some opensource linux application. I have a linux box with two NIC cards and what I thought is the following: Our setup is as follows. Internet comes in through the router and into the firewall. From the firewall it goes into our switch and distributed among the workstations.
I have no access to the router or the firewall as they are centrally configured. I would like to place a device into the loop through which I could monitor the LAN traffic.
Can I put a linux box between the firewall and the switch and have all packets going through registered and logged? I have a proxy server (non transparent) and that captures some but not all. I would like to get all packets registered without interfering with the LAN etc.
I want to connect my home network with the iPhone via UMTS to the internet. I'm searching a Router and Firewall Distribution, which is able to use the iPhone in modem-mode to connect to the internet.
Does anybody know such a Distro which can realize that?
I am trying to do my graduation project, it's labeled under "linux secure router", and I should build a linux based router equipped with firewall and ACL management...Some people advice me to use linux ubuntu distribution todo this I try to do that but I don't know where to start form
View 3 Replies View RelatedI'm mentoring my local high school's IT club as they prepare to participate in a cyberdefense competition (see IT Olympics). Generally we are given four boxes and need to set up a network that provides certain services (which services change from year to year, but usually include a web server, email server, FTP server, and an application server of some sort) and support client PCs that connect from the WAN. The red team then tries to break into our network to steal "flags" from our servers and to set their own "flags" on our servers.
Generally we set up the firewall with two network interface cards (one to the WAN and one to our LAN), and connect the LAN NIC to a router, which then connects to the other three boxes. But we do have the option of installing additional NICs in the firewall and configuring it as a router. I can't shake the feeling that there is a security advantage to such a configuration, but I can't say what that advantage is. Perhaps something with configuring ipTables on the internal boxes to accept connections only from the firewall's NIC, and then only for the services we want that box to support (to prevent an intruder from connecting directly from one box to another)?
I am trying to make a vnc connection from pc #2 to pc #1. Pc #1 is a debian pc behind a zyxel router (P-2602HW-D1A). Pc #2 is a windows xp pc another place at the internet.I have configured the zyxel router to forward incomming trafic on port 5902 to the local ip-adress of the debian box. The debian box is running a vnc server, listening on port 5902.But i dosn?t work.I have tryed to scan the zyxel routers ipadress on port 5902 from the internet, but the scanner says that the port is closed.The vnc server on pc #1 is working fine on the local network. I can connect to the server from a pc on the same side of the zyxel router.Is it deffenitly a router problem, or could it have something to do with debians own firewall?
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