Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [tap]

59 questions
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How to know if a network interface is tap, tun, bridge or physical?

As far as I know, there are 4 main types of network interfaces in Linux: tun, tap, bridge and physical. When I'm doing sys admin on machines running KVM, I usually come across tap, bridge and physical interfaces on the same machine, without being…
user368507
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Making /dev/net/tun available to qemu?

I have created a tap device (tap0) which I would like to provide as a network interface to qemu. I created the device with the following command and attached it to a network bridge I set up: tunctl -t tap0 ifconfig tap0 up brctl addif virbr0 tap0 I…
Nathan Osman
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How to know if a process is attached to a tap interface?

I sometimes come upon machine with tap interfaces (eg, when KVM is running). How can I know which process is attached to the TAP interface?
user368507
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Why is CAP_NET_ADMIN insufficient permissions for ioctl(TUNSETIFF)?

I'm trying to write a tun/tap program in Rust. Since I don't want it to run as root I've added CAP_NET_ADMIN to the binary's capabilities: $sudo setcap cap_net_admin=eip target/release/tunnel $getcap target/release/tunnel target/release/tunnel =…
Teague Lasser
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difference tun/tap, is the interfaces that handle protocols or the OS?

I have difficulties to understand difference between tap and tun interface. I know it is an often asked question and I apologize for that. I asked the same questions on stackoverflow and someone told me to try this forum so I hope I'm in a good…
user2199104
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How to properly configure a tun/tap Interface in linux?

Basically I am trying to create a custom TCP Stack. As you might know I cant use eth0 because linux kernel TCP stack uses that, Due to that I need to create a tun/tap interface and use it for my Custom TCP Stack. /etc/network/interfaces: auto…
Mr. Nobody
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Why are incoming packets on a TAP interface seen with tcpdump but not with iptables?

A program injects packets on a Linux TAP interface (these packets are coming from a virtual machine). Specifically, these are DHCP requests (so they're UDP). I can see the packets with tcpdump but not with iptables, and they don't reach the local…
Gilles 'SO- stop being evil'
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Unable to connect vm to IPv6 internet via virtual tap interface

I'm having trouble connecting a vm to the IPv6 internet through a virtual tap device on the host. I.e., I cannot ping ipv6.google.com or the public IPv6 host global primary interface address. Ex: -bash-4.2$ ping6 ipv6.google.com PING…
waffles
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Create Network Interface from SSH Tunnel

To route your network traffic through SSH, most people would tell you to pass the -D option to create a SOCKS proxy on localhost that you can configure your applications to use. However, a simple proxy isn't the most practical solution for me. Is…
Billy
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How to find the connection between tap interface and its file descriptor?

I have a qemu VM started by an orchestration script, which creates transient tap interfaces. When I inspect the command line arguments of the qemu-system-x86_64 process, then I can see, that the process connects to already opened tap interface with…
Martin
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How can I find out the ownership of a tap interface?

I can set up a persistent Linux tap interface and make it owned by a specific user and group with one of these: tunctl -u someuser -g somegroup -t example.tap ip tuntap add dev example.tap mode tap user someuser group somegroup I can confirm the…
cpbs
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For some reason "sudo ssh -w any -o Tunnel=ethernet root@remote" creates tun devices instead of tap devices

To connect multiple tunnel endpoints to a common bridge interface, I have to create a Layer 2 tunnel over ssh. The server is Ubuntu 10.04, the client is Ubuntu 14.04. I have enabled PermitTunnel yes PermitRootLogin yes in the servers…
jpo234
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Cannot ping a tap device with ipv6 address

I'm running CentOS 7. First I created a tap device: ip tuntap add dev tap2 mode tap Then I assigned ipv6 address to it: ip -6 addr add dev tap2 fd00:4::1/64 ip link set tap2 up Its state generated from ip addr shows: tap2:…
xywang
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how to intercept IP packets on linux

I am trying to achieve this goal on Linux (not sure if it is possible and how if so): I need to write a program to intercept all IP packets on an interface, and deliver this packet to a specific set of user-space programs. By intercept I mean, an…
user2975098
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Theoretical: TAP interface w/ WIFI parent interface

I'm trying to create multiple Linux TAP interfaces and allow them to send/receive packets over a single WIFI adapter. For all intents and purposes I'd like the TAP interfaces to act as full fledged network adapters. They should be able to request…
TheFunk
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