Tagged Questions

0
votes
2answers
59 views

Debian router drops connection

I have a home network with a debian server running kernel 3.8 setup as a router, doing DHCP, DNS-caching, samba and Squid. The motherboard is a Gigabyte GA-Z77X-UD5H with two ethernet ports, one Intel ...
2
votes
1answer
107 views

Configuring ufw or iptables to allow only outbound traffic to the Internet from an internal IPv6 network

How do I configure ufw or iptables to allow only outbound traffic from an IPv6 network to the Internet? I have an office network with a traditional NAT setup for IPv4. I would like to add a PC ...
-1
votes
2answers
122 views

how to forward all traffic from one pc with iptables on router with dd.wrt [closed]

I have been looking for the solutions for days, and I guess it must be fairly easy. I have setup a VNP using a CENTOS box and a router flashed with dd-wrt firmware. I am able to establish the VPN ...
-1
votes
1answer
450 views

CentOS Dual WAN - Load Balance and Failover

I am setting up a Linux server (CentOS) to act as a router with load balacing and failover (when one internet line is down, another one should take over). The clients conected to eth1 ( LAN ) should ...
0
votes
1answer
39 views

IP Tables though Simple Router Machine

I have being setting myself up a router, for mainly for dns+dhcp functionality (mess about with alot of virtual machines). I have two interfaces eth0 and eth1. Eth0 can be see as the WAN with eth1 for ...
1
vote
1answer
845 views

How do I configure iptables in DD-WRT to block Skype on br1 only?

Using DD-WRT on a Linksys router, I've got a private network set up as br0 and a guest network set up as br1. I want to block access to Skype on only the guest network, and the easiest way I've seen ...
1
vote
2answers
246 views

Configure DD-WRT as a router

Here's what I've got in my small office: - a static public IP address - 8 IP subnet configured like this xx.xx.xx.16 - network xx.xx.xx.17 - gateway xx.xx.xx.18 - 22 usable ...
3
votes
2answers
222 views

How can private IPV4 addresses get past iptables NAT (tcp RST,FIN)

I've got a router performing simple NAT translation using iptables iptables -t nat -o -j MASQUERADE This works fine almost all of the time except for one particular case where some TCP RST and FIN ...
2
votes
3answers
136 views

iptables intercept local traffic

I hope someone can help me out with a somewhat simple task. I'm trying to redirect a client in my router through my desktop PC, so I can dump the traffic and analyze it (its potential source of ...
1
vote
0answers
152 views

Connect two networks

Connecting two different offices with a wireless link and linux boxes. Hardware: 2 CISCO RV42, 2 Dual Homed Linux Boxes running debian, 2 2Wire and 2 AirMax 5 Configuration is: Office A LAN A ...
0
votes
1answer
360 views

Outside to port 80 doesn't work with IPTables with Squid

IPTables rules : # RESET iptables -F iptables -t nat -F iptables -t mangle -F iptables -X # Pas de filtrage sur l'interface lo iptables -A INPUT -i lo -j ACCEPT # Debut des reles de firewall ...
-1
votes
2answers
1k views

Destination NAT Onto the Same Network from internal clients

I have a DSL router which acts as NAT (SNAT & DNAT). I have setup a server on internal network (10.0.0.2 at port 43201). DSL router was configured to "port forward" (or DNAT) all incoming ...
2
votes
1answer
210 views

iptables gateway not working on clients

I am not sure what's going on, but I have setup a gateway debian box with iptables and dhcpd server. The server is handing out the ip addresses to the clients just fine, gateway being set to the ...
1
vote
2answers
804 views

backup static route on linux router

How do I set up a backup static route on a linux router. For example if I have 2 routers R1 and R2, connected through a switch, through two links: R1(eth1)->switch->R2(eth1) R1 ...
1
vote
1answer
376 views

Redirect external router port to external IP and port

I have a WRT54GL home router and I want requests coming to the router public IP address on port 97 to be redirected to an external IP and port, for example 209.85.148.99 (google.com) and port 80. The ...
8
votes
1answer
706 views

Limit ICMP Per Source IP with IPTables

I have mistakenly thought that the limit module is per source ip, but it appears to be based on all requests: 577 36987 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/0 ...
0
votes
1answer
237 views

Bridging and routing IPv6 Router Advertisements

I have a bridge called "br01" in which the interfaces "eth1" and "eth0" are participating. There is a rule in the broute table of ebtables that drops RAs when they arrive in the interface eth1, so the ...
1
vote
2answers
196 views

Simple Port Forwarding

I have searched and searched and tried several different things and have not been able to fina solution. Here's my situation: node1 has 2 interfaces: eth0 (Public IP: 56.X.X.X), and eth1 (Private ...
1
vote
1answer
182 views

looks like conntrack utility is installed but i cannot find it

Ive been told to use the 'conntrack' utility (http://linux.die.net/man/8/conntrack) for some purpose. now as in the description writen: conntrack -L Dump the connection tracking table in ...
2
votes
3answers
2k views

Purpose built router/firewall vs Linux iptables/Shorewall

I'm in the process of figuring out what types of devices I'll want to use at a new colo install. We have some experience configuring Cisco routers but our knowledge is much deeper on the Linux ...
2
votes
5answers
249 views

Linux Traffic Logging

I'm looking for a good free method of logging IP heading information (src/dest IP with timestamp) passing through a Linux router. I know I can do this with tcpdump -i eth0 > log.txt However I'm ...
0
votes
1answer
660 views

writing an iptables rule which forward OSPF packets from one interface to another

In a given machine I have got two interfaces eth0 and eth1. Cisco routers are connected, to both interfaces, eth0 and eth1 and I want OSPF packets which arrives on eth0 to be forwarded to eth1 and ...
1
vote
2answers
200 views

How to get rid of NAT in a LAN?

Currently the LAN I manage is organized as follows: internal network (192.168.1.0) which uses a Linux server as a gateway (internal address on interface br0 192.168.1.1, external address on interface ...
4
votes
2answers
1k views

Using iptables to block ALL outgoing traffic from one NIC?

I must pretty bad at Googling as this seems like a very basic question but I can't seem to find the answer anywhere... and man iptables is a very long read! I have two NICs - eth0 and eth1 - on a ...
0
votes
1answer
146 views

SCEP routing using iptables

Does anyone know about SCEP routing table on linux? I would like to know if it is possible using software routing to scep requests go to another machine then usually goes using 443 or 80? tks
2
votes
2answers
561 views

Public IP behind NAT firewall

I have a Linux NAT Firewall serving a virtual machine infrastructure. Right now all the VMs use NAT, but I'd like to have some of them to use a public IP that is not NATed. I have a range of IPs: ...
2
votes
2answers
4k views

How to forward UDP Wake-on-Lan port to broadcast IP with IPTABLES?

I'm trying to setup Wake-on-Lan for some of the LAN computers at home and it seems that I need to open a UDP port (7 or 9 being the most common) and forward all requests to the broadcast IP, which in ...
3
votes
2answers
2k views

Port forward localhost:port to lan:port using iptables - how?

Is there a way I can map 127.0.0.1:3389 to 192.168.1.2:3389 (with iptables? That is, all connections to localhost:3389 will be redirected to my LAN machine? The reason for that is as follows: my ...
0
votes
3answers
1k views

iptables on dd-wrt for church network

I'm attempting to set up a firewall on my church's WRT54GL running dd-wrt v24. I've not found many good guides at setting up a firewall, and nothing that seems to be recent enough with these routers. ...
2
votes
5answers
286 views

problem with NAT in a multiple uplink scenario

I'm trying to configure a linux pc-router that must deal with routing and using NAT to provide connectivity to an internal network (it's also the DHCP server and firewall). In the external side the ...
2
votes
1answer
510 views

Cisco ACL Style Rules for IP Tables on a Linux Router

I have more of a Cisco background than Linux when it comes to routers. When designing my firewall rules I am used to thinking of in our out ACLs attached to specific interfaces. I am thinking I can ...
11
votes
3answers
888 views

Can you recommend a good intro to iptables?

I have to setup a firewall on a Linux server (all my previous experience is with Windows). My rules are meant to be pretty simple - forbid all, allow some ports with all, allow some ports for specific ...
1
vote
3answers
873 views

Bridge 2 routers

I have 2 Linksys WRT54GL routers flashed with DD-WRT. On each I have a different ISP, and thus a different private network. I would like to be able to talk to either network regardless of what network ...
1
vote
2answers
1k views

routing specific IP to ppp0 tunnel

I feel I've struggled with this long enough and need some help. I have a pptp tunnel and am trying to route destination traffic from 208.85.40.20 to the pptp tunnel (ppp0). (Keen observers may ...
1
vote
2answers
1k views

Monitoring traffic on linux router for syn-flood

We have a linux server (Debian-Lenny) with solid-state drive, without hard disk classic. He's use as a router, so traffic is only for forward. We want to monitor connexions in able to find some ...
2
votes
1answer
1k views

Why isn't ICMP routing with iptables nat routing

I'm using iptables on Ubuntu server to route a public IP to a private IP. I want to nat all traffic, including 80, 443 and ICMP. However, it appears that ICMP isn't routing. I have a steady ping ...
1
vote
1answer
2k views

How to use virtualbox to simulate a sub network with the host as router?

I am currently working on QoS router functions using iptables and tc on Linux. I would like to use virtualbox to simulate a computer plug on my router (The router would be the host) Physically, I ...
6
votes
7answers
2k views

How do you manage your Linux iptables configuration on a machine acting as a router?

I have a couple Linux machines that act as routers/firewalls for my networks and I have a script that runs all the iptables commands to set my rules. This seems to me like a really silly way to do it ...