New answers tagged networking
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Why netcat doesn't use the right interface associated with the IP?
Simple answer
Linux Kernel has two packet queues in kernel, one for sending packets, and one for received packets.
And Kernel decides (based on routing table and destination address, to which NIC ...
- 101
1
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Accepted
raise network interfaces - debian 12
There is only one default gateway: the default gateway used in the default route, which is what gateway controls. The second time the network configuration tools attempt to add a default route with ...
- 33.4k
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How do I find out reason of missing packets in response to `sendto` syscall?
There is no guarantee that a machine can hear its own packets, especially UDP packets. So if you ran tcpdump on the same machine as sendto(), then you have found expected behavior even if the sendto ...
- 6,223
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Managing multiple low-quality wifi connections, dynamically switching to whichever has the best quality
I've written a bash script to help with this: https://github.com/waltinator/net-o-matic It watches the connection, and when the connection drops, does a user-specified thing to try to reconnect or do ...
- 4,709
0
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Accepted
Communicate With Multiple Devices Using One IP
Linux has what is called virtual bridge devices, which you can use to make a network consisting of multiple physical and virtual Ethernet interfaces. In your case, you'd set up a bridge with the two y ...
- 25k
0
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Accepted
linux bonding active-backup mode set priority for multiple interfaces?
The kernel documentation on bonding describes how to set the priority of an interface participating in a bonding interface with compatible modes:
prio
Slave priority. A higher number means higher ...
- 33.4k
1
vote
Accepted
Load iptables or nftables rules as fast as possible during boot and before the network interfaces be put online
In Debian 12, iptables is by default a wrapper for the new nftables subsystem. The iptables-persistent package depends on package netfilter-persistent, which creates a service named netfilter-...
- 90.5k
0
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Load iptables or nftables rules as fast as possible during boot and before the network interfaces be put online
Depends on your distro, e.g. Fedora Linux does that for you. It's weird your distro doesn't - that's a security vulnerability absolutely worth reporting and fixing. Systemd has dependencies for ...
- 27.3k
2
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tcpdump doesn't appear to call any libpcap's exported function
strace shows only system calls. ltrace is a tool for showing library calls (see Difference between system call and library call).
If you want to see both system calls AND library calls, you can add ...
- 4,025
0
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Automatically set Linux timezone according to location
Install geoclue. Ubuntu/Debian: sudo apt install geoclue-2.0. Arch Linux: sudo pacman -S geoclue.
If you are using GNOME Classic (for regular GNOME it should be similar):
Go to Settings -> Privacy ...
- 1,179
1
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Finding out all blocked port numbers
You could try to reach an external server that has all ports open like http://portquiz.net/
http://portquiz.net:80/
http://portquiz.net:81/
http://portquiz.net:6881/
This server listens on all TCP ...
- 127
1
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Stay on a port listening to understand why it closes with which error
Based on the tags of the question, you are using bash on a mac. The best way to see what is happening on a port is tcpdump.
Based on the port 8080 being used, I am assuming it is standard http ...
- 147
1
vote
Advertising an HTTP/SOCKS proxy over local network
For the HTTP proxy part this can be done via DHCP.
While you can set the proxy URL in your PAC file to point to a socks server (using the socks scheme) that's somewhat redundant if you have a working ...
- 5,203
0
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Blocking all ports but a few in iptables
Simply specifying a network interface like this:
iptables -N WHITELIST
iptables -A INPUT -j WHITELIST
iptables -i wlan0 -A WHITELIST --protocol tcp --match tcp --dport 4444 --jump ACCEPT
iptables -i ...
- 26
0
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No longer able to enable my network interface in Centos 8
You could try this
nmcli n off
then
nmcli n on
It worked for me when I shutdown an CentOS8 then turn it on, the network interface (in this case ens160) couldn't be up and have error "device lo ...
1
vote
Accepted
How to configure bridged networking for KVM virtual machines in Kali Linux host?
The problem here is not Kali. While I in general agree that Kali is not a good choice if you don't need Kali, it should support bridging.
But bridging with wifi is difficult.
In this case I would ...
- 263
1
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fstab mount wait for network
Instead of fighting systemd assumptions and legacy options which may or may not work, make your service and make your mount target depend on it.
My SMB shares are mounted from 192.168.1.2, change to ...
- 111
0
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SSH Connection into home network without port forwarding
without any port forwarding.
But what you're doing is a port forwarding (through an SSH tunnel)!
So, if you want to achieve that, it would seem intuitive that instead of assigning each RPi its own ...
- 25k
1
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How to route traffic from ethernet interface to another?
Your eth2 IP address starts with 192.168, which means it is not a public IP in the first place. Your eth2 interface must be connected to a router, firewall or some other NAT-capable device that holds ...
- 90.5k
2
votes
Accepted
default gateway not set when using bond0 interface
Among multiple ifupdown implementations, I'll consider it's ifupdown (implementation "v1") and the interfaces(5) configuration as seen on Debian.
The bond0 stanza should not use the keyword ...
- 33.4k
2
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Are Avahi and Bonjour compatible?
Yes, Avahi and Bonjour are both implementations of Multicast DNS (mDNS) and DNS Service Discovery (DNS-SD), which are standardized by the IETF and fully compatible. For printing specifically, CUPS, ...
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-1
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How to measure network transfer speed against a host from the command line?
Many hosts will be on the internet and outside my control.
You basically can't. The other host has to cooperate with you; it can cooperate in the sense that it sends data in response to a HTTP ...
- 25k
0
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Orphaned connections in CLOSE_WAIT state
While the answer of Mikel is likely also correct that kernel-side sockets like NFS can cause this, CLOSE_WAIT - entries without associated FDs are more often:
Connections that were closed by the ...
- 1,691
0
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How to get Wireguard VPN to connect over Tor?
From the Tor project official website support pages:
What about distributed denial of service attacks?
[...]
But because Tor only transports correctly formed TCP streams, not
all IP packets, you ...
- 33.4k
1
vote
Running arbitrary binary program with cluster computers
It sounds like you are looking to merge system resources across multiple Linux instances. This is not totally possible, especially for RAM and CPU. For disk space NFS and other network shares can ...
- 18.4k
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