Questions tagged [tunneling]

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How do I configure OpenVPN as a Gateway client for Witopia?

I have the following setup: Witopia SSL account Synology 409 NAS (with OpenVPN and Apache etc) PS3 Mac Apple AirPort router (configured for NAT) Locked IPT-box (using DHCP and NAT traversing) &...
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0answers
89 views

How to unwrap a tunneled packet in iptables/netfilter and process the tunneled packet

I have a specific question regarding the Linux netfilter/iptables interaction. Let's say I have an IP packet P1 inside of another IP packet P2 (that is, P1 is tunneled). Now, the question is as ...
3
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1answer
138 views

What is the best way to create remote tunnel?

I have 3 Linux servers: 10.0.0.0/24 - (10.0.0.10) Linux server inside my LAN. 20.0.0.0/24 - (20.0.0.10) Linux server with HTTP Apache server 50.50.50.50/32 - Server on Amazon AWS which see both ...
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0answers
320 views

using udptunnel with openvpn

I'm trying to tunnel openvpn traffic (UDP protocol) over a firewall using udptunnel I can't use openvpn itself on TCP protocol. On the server I'm running udptunnel like this: udptunnel -s 9999 127....
2
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0answers
177 views

Multiqueue tun/tap interface

I am trying to understand how Multiqueue tuntap interface works. Following the instructions provided at: https://www.kernel.org/doc/Documentation/networking/tuntap.txt I was able to create multiple ...
2
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1answer
563 views

SSH Configuration Help / Can't tunnel

I have a stock install of Ubuntu 16.04.2 with key based authentication setup and working fine. I've also installed an unmodified mysql-server 5.7.17. I cannot seem to connect to the mysql server via ...
2
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0answers
544 views

Why could policy routing on iptables marks applied in FORWARD or OUTPUT chains be inconsistent?

I am routing HTTPS connections down a SSH tunnel (-w) using iptables marks and iproute2 rules, the reasons I need to do it this way are contrived, to say the least, so most alternate solutions may not ...
2
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0answers
744 views

More than 255 Linux GRE tunnels

Is it possible to set up more than 255 GRE tunnels in Linux? It seems that 255 is the default maximum, but is there any way to increase the limit?
2
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0answers
186 views

debugging iptables when tunneling one VPN through another

I seek to tunnel one SSL VPN (F5, running on my debian laptop==client) through another (OpenVPN, running on a debian linode==server), but lose all client networking (including, e.g., ping) after the ...
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0answers
2k views

how to open up socks/SSH on different network interfaces?

iptables -A PREROUTING -i usb0 -t mangle -p tcp --dport 8080 -j MARK --set-mark 1 iptables -L Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD ...
2
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0answers
1k views

IPsec Tunnel mode - RoadWarriors configuration

I've the need to configure IPsec tunnel mode between a gateway with static NAT (let's say its public IP is 172.31.0.105) and a number of clients that are behind dynamic NAT. Reading through some ...
2
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1answer
1k views

Dynamic port forwarding using socat

I'm trying to replicate the functionality of ssh -D <PORT> user@machineX to tunnel all my traffic from my current machine via machineX. I do not need the ssh shell open at all, I simply wish to ...
1
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1answer
672 views

Error using openssl with socat - SSL3_CHECK_CERT_AND_ALGORITHM:dh key too small

Short Version of Question Assuming the existence of the relevant files, why does the following sequence of commands not work? socat tcp-listen:10001,fork exec:'/bin/cat' & socat openssl-listen:...
1
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1answer
282 views

OpenVPN or IPtables for split tunnel control?

I have been plugging away but not luck, but from what I understand what I am trying to split tunnel. I have a VPN in place (and working) where all traffic from my LAN heads out to the internet via ...
1
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0answers
161 views

How to keep reversed SSH tunnel alive and safe

I need to SSH to a computer that is behind a NAT. To this end a reverse SSH tunnel from that computer (with SSH server installed) is established to my publicly visible server (middleman.example.org): ...
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0answers
291 views

SSH Tunnel broker over IPV4 for machines behind CNAT

I am not sure if I should be asking this in Unix & Linux or Network Engineering Here is the physical scenario [Host 1]----[Carrier-grade NAT]---->AWS<----[Carrier-grade NAT]----[Host 2] ...
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0answers
977 views

Replace ip tuntap by /etc/network/interfaces (or how to create a tun interface in /etc/network/interfaces)

I'm using a sh script (pasted below) to create an IPv6 tun interface using iproute with the tun mode. #!/bin/sh # Create a new TUN interface for WPAN interaction. ip -6 tuntap add mode tun tun0 # ...
1
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1answer
450 views

How to rsync between two server via their common windows host

We are migrating 100s of gigs of data from in house server to external server. We tried a lot but still those two servers can't talk to each other, probably due to corporate security. The current ...
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0answers
245 views

ip tunnel from subnet to local host

I'm very new to Linux networking. I need to set up an IP tunnel so that all udp traffic coming to the 12.x.x.x subnet gets tunneled to a specific ip and port on the same box so that my application ...
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0answers
451 views

IPv6 packets injected on tun interface go up to IPv4 stack

I have a problem about tun interfaces and the IPv6 handling by the kernel. I'm trying to provide IPv6 to the end-users of my network over a pure IPv4 network. Summarizing (just a tunneling background ...
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0answers
480 views

Trying to “reverse proxy” requests to a VPS IP to an internal server over OpenVPN, how to do the routing tables automatically?

Brief description I've got two systems, a VPS which is connected directly to the internet, and a system in my basement behind my router (NAT). I'd like to take the VPS and forward all requests on one ...
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0answers
284 views

How to create a GRE tunnel from IPv4 address to IPv6 address?

Is it possible to tunnel from an IPv4 address to IPv6 address? The IPv6 server is a large server allowed a single IPv4 address but virtually unlimited IPv6 addresses, so I want to connect IP ...
1
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1answer
540 views

TCP over TUN: SYN/ACK is received, but no ACK is generated, and socket remains in SYN_SENT state

I am tunneling an outgoing TCP connection over a TUN interface set up by a program I wrote. The TUN interface basically just relays the packets to/from a proxy server, with minimal modifications (...
1
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1answer
1k views

tun2socks (badvpn) - having trouble with setup

I am attempting to use tun2socks/badvpn to force all traffic through the tun device, but am having some issues. From wireshark, it appears that traffic is indeed going out properly, but not coming ...
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0answers
122 views

Can I change owner of a tunnel after creating it?

I've been trying to finagle pytun to do my bidding in creating persistent ssh tunnels, but I very much do not want these to be owned by root and unless I modify the python package myself (which as a ...
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0answers
138 views

Why is a Linux Tun interface not returning ICMPv6 Echo replies?

I wrote a program which connects to a TUN interface and replies to ICMPv6 Echo Requests. Even though I can successfully observe the echoes and replies with tcpdump on the TUN interface, it appears ...
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0answers
79 views

Tunslip deactivates WiFi in raspberry pi B+ board

I'm using Contiki operating system with Cooja to simulate a sensor node network. And I'm trying to capture the ip packets it's sending in a Raspberry Pi B+ board (through USB) using tunslip6 and a ...
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0answers
387 views

It is possible to make an IPSEC VPN Bonding?

I wanted to know if It is possible to bound two IPSEC tunnels ? I've already done a VPN bonding of SSH tunnels, but It will be better if I use IPSEC.
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0answers
604 views

SFTP connect through an other server

I want to connect to my account in a server of my university. When I’m there I only have to do ssh user@FinalServer/home/user or create a folder using sftp://user@FinalServer/home/user But the ...
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0answers
121 views

Transparent proxy to other IP of thousand ports

I was bought a service that only allow a IP, the IP that i say, only one, but I need use this from more IP's. I think that I can install in this computer a system to do a transparent proxy for ...
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0answers
586 views

Establish IPSEC Tunnel between two Ubuntu 12.04 PCs over LAN

I have two ubuntu 12.04 32 Bit PCs between which I want IPSec Tunnel to be setup. I have setup ipsec in both systems and ipsec verify runs fine on both. Since I have no prior experience of openswan, I ...
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0answers
251 views

How to get information from sshd about established remote tunnels

I have a server running on which from many different places people log on via ssh and open remote ssh-tunnels to other places behind different firewalls. Now I want to try to get an overview, which ...
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0answers
717 views

Packets sent through TUN interface not routed

I have a C program attached to a TUN interface. In my C program, I'm building packets and writing them to the TUN interface. Now to check if packets are really sent from my TUN interface I use ...
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0answers
296 views

Local Client/Server communication using TUN interfaces

I want to establish a local communication between a client and a server using TUN interfaces. The client program will be attached to interface TUN1 and we suppose that it has IP address @IP1. The ...
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0answers
1k views

How to redirect/forward between a tun/tap device and a socket using linux tools?

I have a socks5 proxy that is bind to eth0. It opens two ports, Port1 is used to connect to remote (for example a http server), Port2 is to listen for clients to connect. Then I created a tun device. ...
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0answers
1k views

Packets not received by TUN device

I created a TUN device(nat64) and created a route so that all the required packets are forwarded to the TUN device from an eth device. But, I see that many packets are not received by the TUN device. ...
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0answers
30 views

Tunneling TCP via ICMP slowness

There is: Server "A" Server "B" I have root permission on both. They can ONLY ping each other. I installed ptunnel on both. On Server "A", I tried to: ptunnel -p SERVER-B-IP -lp 6969 -da SERVER-...
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0answers
29 views

Forward traffic between two hosts, first with a few IP, second with 1 IP and lxd containers

I have a task to create connections between host A with a few IP addresses, say: 1.2.3.4, 1.2.3.5, 1.2.3.6, 1.2.3.7 host B with 1 IP 2.3.4.5 On host B there two lxd containers lx1, and lx2. The goal ...
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0answers
47 views

Pernament tunnel at every boot in CentOs 7

I want to have my tunnel UP at every system restart. It is my non persistent solution: ip tunnel add vti0 local 222.222.22.222 remote 33.333.333.333 mode vti key 41 ip link set vti0 up ip addr add ...
0
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1answer
129 views

How do I create a persistent tunnel device in sles15 (with or without wicked xml config)

I'm trying to simplify some of my configs for sles15, pushing out tunnel configs to my machines via ansible. Currently whenever I configure a tunnel, I do it on the fly using ssh from the machine ...
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0answers
34 views

ipsec per user id routing

could someone point me out how should look the config of ipsec (libreswan) the way that i could assign a static public ip per user id we use ipsec xauth/psk left (client) ipsec identifier based on ...
0
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1answer
90 views

SSH: instruct backgrounded tunnel to exit on broken pipe?

I frequently start background SSH tunnels using the ... -f -N -L ... options. This works great, until for example I sleep my machine, or my VPN credentials expire, when the tunnels stop working and I ...
0
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1answer
1k views

Can't forward traffic from eth to TUN/TAP

I'm trying to forward traffic from a physical interface enp5s0 to a virtual one tun0. The goal is to make tun0 receive essentially all packets from enp5s0. First, I enable forwarding with a command ...
0
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0answers
59 views

Using two IP connections in parallel for resilient delivery

I have a mobile Linux server with two LTE connections to the internet, via different providers. The mobile server also acts as a router for other devices, currently using masquerading on just a ...
0
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1answer
45 views

Two OpenVPN tunnels to different networks configuration setup to work simultaneously for Linux

I have 1 machine that has OpenVPN tunnel setup with 1 external network computer. Now i want to add another external network computer with a new tunnel. Config file for currently operating tunnel ...
0
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1answer
580 views

ssh reverse tunnel & gateway ports: forwarding users real (public) IP address?

I'm using a reverse tunnel to a public vps so users can connect to my machine at home. However, due to the reason the reverse tunnel works, their IP addresses are shown as local (127.0.0.1) to my ...
0
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1answer
203 views

Security of a SSH tunnel

We have a cluster (currently 10 machines) behind a NAT. There is a NAT gateway/jump-host between the private network and the regular company network. Users can ssh to the jump-host and then get into ...
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0answers
515 views

wget probelm with a tunnel connection using ssh

I know this is not a new question, but I have researched a bit and so far none of the answers I've seen gave me the answer. I have this situation: I´m working on a campus where the network is highly ...
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0answers
115 views

How to get informed about EVERY incoming ssh connection (e.g. with no remote command specified)

The case I'm used to set up automatic reverse ssh tunnels to remote computers via my server with cron. Usually I use the following entry: @reboot sleep 300 && ssh -MNf -R xxx22:host:22 user@...
0
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1answer
522 views

Redirect traffic through the server

My task is to redirect traffic (port range) through the server. Here is the schema: Why NAT is not appropriate here: If NAT is set to "Tunnel Server", then all users will be assigned the same IP. ...