ipv4

raise network interfaces – debian 12

raise network interfaces – debian 12 I’m trying to add one main IP, two extra IP and one IP6. Here is my interfaces file located at /etc/network/interfaces: source /etc/network/interfaces.d/* auto lo iface lo inet loopback allow-hotplug ens192 iface ens192 inet static address 23.227.198.250/26 gateway 23.227.198.194 dns-nameservers 8.8.8.8 dns-search deb12.domain.com auto ens192:0 iface ens192:0 inet static …

Total answers: 1

Ipv6 vs Ipv4: is there a way to force ipv6 use?

Ipv6 vs Ipv4: is there a way to force ipv6 use? Ubuntu/Linux beginner here, so I was wondering if there’s any way to force Ubuntu to prefer IPv4 or IPv6 when resolving a name (ex.: google.com has ipv4 and ipv6 addresses. is there any setting which allows me to say that IPv6 should be preferred …

Total answers: 1

dhcpd or dhclient not found

dhcpd or dhclient not found I’m working on a custom Ubuntu 20.04 server and am trying to get a dhcp IP for it. The server has so far run on a static IP and when I run dhcp or dhclient it says dhcpd: command not found and dhclient: command not found. The /sbin has no …

Total answers: 1

Problem with my iptables configuration on reboot

Problem with my iptables configuration on reboot I tried many times to save the iptables configuration to have it start up automatically when I reboot my Raspberry Pi (Ubuntu 22.04.1 LTS) but when I look with this command: $ sudo iptables -L my chain rules are gone after a reboot. I followed this documentation: https://help.ubuntu.com/community/IptablesHowTo …

Total answers: 1

Highest performance way to route traffic from IPv4 to IPv6 on Linux?

Highest performance way to route traffic from IPv4 to IPv6 on Linux? I have a use case where I want to forward certain IPv4 ports incoming into a machine, to to the same ports on another machine that uses IPv6. I assume I can do this with [auto]ssh, but wonder if this is high performance, …

Total answers: 1

ping google.com within the Oracle Linux 9.1 VM is not working

ping google.com within the Oracle Linux 9.1 VM is not working I have installed the Oracle VM VirtualBox in my laptop. Then I downloaded the Full ISO image for Oracle Linux 9.1 version (via https://yum.oracle.com/oracle-linux-isos.html) and used that in order to create an Oracle Linux (64 bit) virtual machine. The installation was successful and I …

Total answers: 1

Change IPv4 address of my server

Change IPv4 address of my server I’ve tried to change de IPv4 address from my Ubuntu Server but when i run the command "netplan apply" an error appear, the error appeared is telling me my gateway isn’t a valid IPv4 Address. Someone can help me please. I’m a beginner with servers. I know this is …

Total answers: 1

How do packets flow through the kernel

How do packets flow through the kernel When it comes to packet filtering/management I never actually know what is going on inside the kernel. There are so many different tools that act on the packets, either from userspace (modifying kernel-space subsystems) or directly on kernel-space. Is there any place where each tool documents the interaction …

Total answers: 1

My Ping result are returning an IPv6 instead of IPv4

My Ping result are returning an IPv6 instead of IPv4 I am new in Linux. So, I am running dual boot Linux and Windows 11. All my OS is on the latest version. I try to ping google.com in Linux, but I get returned IPv6 instead of IPv4. Here is the ping result: $ ping …

Total answers: 1

How can I get the ipv4 address from `ip link` like I used to see with ifconfig?

How can I get the ipv4 address from `ip link` like I used to see with ifconfig? When I run ip to get the ip address, I’m getting $ ip link 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: wlp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 …

Total answers: 1

IPv6 is working, but IPv4 isn't

IPv6 is working, but IPv4 isn't I’ve got a new laptop running Ubuntu 16.04 that worked like a charm for a couple of weeks but has now lost its appetite for connecting to the internet via Wi-fi. I know it’s not a problem with my router or ISP, because I’m writing this post using my …

Total answers: 6

Bash: Extract one of the four sections of an IPv4 address

Bash: Extract one of the four sections of an IPv4 address We can use the syntax ${var##pattern} and ${var%%pattern} to extract the last and first section of an IPv4 address: IP=109.96.77.15 echo IP: $IP echo ‘Extract the first section using ${var%%pattern}: ‘ ${IP%%.*} echo ‘Extract the last section using ${var##pattern}: ‘ ${IP##*.} How we can …

Total answers: 10

wget uses ipv6 address and takes too long to complete

wget uses ipv6 address and takes too long to complete On a server wget-1.16 takes 8 minutes to complete: $ wget http://http.debian.net/debian/dists/stable/Release -O – –2017-06-12 23:44:40– http://http.debian.net/debian/dists/stable/Release [4693/5569] Resolving http.debian.net (http.debian.net)… 2001:4f8:1:c::15, 2605:bc80:3010:b00:0:deb:166:202, 2001:610:1908:b000::148:14, … Connecting to http.debian.net (http.debian.net)|2001:4f8:1:c::15|:80… failed: Connection timed out. Connecting to http.debian.net (http.debian.net)|2605:bc80:3010:b00:0:deb:166:202|:80… failed: Connection timed out. Connecting to http.debian.net (http.debian.net)|2001:610:1908:b000::148:14|:80… …

Total answers: 1

Installing vsftpd – 500 OOPS: could not bind listening IPv4 socket?

Installing vsftpd – 500 OOPS: could not bind listening IPv4 socket? I have to set up a FTP server on my machine. I have installed vsftpd using the command: sudo apt-get install vsftpd I then edited the configuration file vsftpd.conf in the location /etc. The file contains: #Set the server to run in standalone mode …

Total answers: 8

Can I prevent a default route being added when bringing up an interface?

Can I prevent a default route being added when bringing up an interface? I have a system with two NICs on it. This machine, and a few accompanying devices will be moved and attached to different LANs or sometimes it’ll be using dial-up. eth0: – 10.x.x.x address space – no internet gateway – only a …

Total answers: 8

netstat — why are IPv4 daemons listening to ports listed only in -A inet6?

netstat — why are IPv4 daemons listening to ports listed only in -A inet6? I have a computer with: Linux superhost 3.2.0-4-amd64 #1 SMP Debian 3.2.60-1+deb7u3 x86_64 GNU/Linux It runs Apache on port 80 on all interfaces, and it does not show up in netstat -planA inet, however it unexpectedly can be found in netstat …

Total answers: 2

Can TCP provide more than 65535 ports?

Can TCP provide more than 65535 ports? Is it possible to setup a Linux system so that it provides more than 65,535 ports? The intent would be to have more than 65k daemons listening on a given system. Clearly there are ports being used so this is not possible for those reasons, so think of …

Total answers: 3

Detect other machine's address in link local?

Detect other machine's address in link local? I have two machines connected in link local IPv4 over a CAT6 cable. Is there a way from host1 that I can determine host2‘s IPv4 address? I’m on an Debian-derivative running kernel 3.2.0-34-generic. Asked By: Naftuli Kay || Source Yes, already posted in the comments as a verified …

Total answers: 1