Scanning the machine on the LAN with my laptop, I got this: gabriele @ osiris { ~ } [ Tue Oct 07 ] [ 08:49 PM] nmap -sP 192.168.1.236 Starting Nmap 6.40 ( http://nmap.org ) at 2014-10-07 20:50 CEST Nmap scan report for ---.homenet.telecomitalia.it (192.168.1.236) Host is up (0.0044s latency). Nmap done: 1 IP address (1 host up) scanned in 0.03 seconds nmap won't recognize the nostname, putting—in place of "mercury" and I assume is not a problem of nmap because it doesn't even access in this way: root@mercury when I changed the hostname I follow these steps sudo nano /etc/hostname and I wrote a single line with "mercury", then: sudo nano /etc/hosts with this configuration: 127.0.0.1 localhost 127.0.1.1 mercury localhost ::1 localhost ip6-localhost ip6-loopback fe00::0 ip6-localnet ff00::0 ip6-mcastprefix ff02::1 ip6-allnodes ff02::2 ip6-allrouters and finally: sudo /etc/init.d/hostname.sh start am I doing something wrong?

I recently changed some stuff with my home network, and the changes sparked a few general networking questions (below is a diagram of what I'm working with): - Context: - For both Setup A and Setup B, the ISP modem is *not* in Bridge mode. - *Setup A*: - local IP of the Pi was 10.0.0.9. - I was able to SSH from my laptop to the Pi using the 10.0.0.9 IP address. - I was able to SSH from the R320 to the Pi using the 10.0.0.9 IP address. - *During the transition from Setup A to Setup B*: - Local IP of wlan0 of the Pi was 10.0.0.9 - Local IP of eth0 of the Pi was 10.0.0.8 - I was able to SSH from my laptop to the Pi using both 10.0.0.9 and 10.0.0.8. - *Setup B*: - According to my router: - 10.0.0.9 is the IP of prodpi (this is what I named the Pi when I installed the OS). - 10.0.0.8 is the IP of Raspberry Pi. I am unable to ping or SSH using this IP address. - According to the TP-Link network: - 10.0.0.10 is the IP of prodpi - I am *unable* to SSH from my laptop or the R320 to 10.0.0.8 - I am *unable* to SSH from my laptop to 10.0.0.9, however I am able to SSH from the R320 to 10.0.0.9. - I am able to SSH from my laptop and the R320 to 10.0.0.10. - Questions: - Do IP addresses point to a specific machine, or do they point to a specific *network interface on a specific machine*? - Why would I be able to SSH to 10.0.0.9 from the R320, but not my laptop in Setup B? - Why does my router say 10.0.0.8 is assoicated with a Raspberry Pi host, but I can't ping it?

I want to use services like Barrier on my university network but LAN is prohibited on it. To fix this, I directly connected an ethernet cable from my laptop to the PC I wanted to control and followed the steps shown in https://askubuntu.com/a/1276657 . It works, but now I would like to route my laptop's wifi internet traffic to my PC. Is there any way to do this using NetworkManager and/or bridges and/or NAT? It does not matter to me if the two computers share a local IP address.

I'm trying to make some simple decentralized DNS for my local network. The trouble is that every time I add a new machine, the other machines on the net can't find its name automatically because it has to be manually added to the resolver's table; I want this to be done automatically. Let's say that I have a computer with the hostname continua that was recently added to the network and has a dynamic IP address, so to connect to that machine from another point on the net via SSH, FTP, ping, etc., I first need to know its IP, what forces me to scan the network for a new device or check the router DHCP table. So instead of calling: ssh continua I have to do it by its dynamic IP: ssh 192.168.1.xxx The simplest way to solve that is to set the new hostname table on the router's DNS, but it becomes impractical if I have to do this many times. I plan to make every computer on my network able to resolve its name via simple DNS running locally and then send this information to the upper DNS on my router. But I don't know how to do this middle step. I actually installed dnsmasq on one of my computers, and it correctly resolves itself over the local network, so what I am thinking is there a way to add broadcast as a DNS server in resolv.conf? Something like 192.168.1.255?

I am currently working with the KSZ9897 Ethernet switch connected to an RSB3720 board. The Ethernet ports have been configured correctly, but I am encountering an issue with the LAN7801 USB-to-Ethernet adapter when attempting to initialize the PHY. Details: Board: RSB3720 Switch: KSZ9897 Adapter: LAN7801 (USB-to-Ethernet) Kernel Version: 5.15 Issue: The LAN7801 is unable to detect the PHY driver, as indicated by the kernel logs. Kernel Logs:

[ 2586.345280] TRACE 1 of_mdiobus_register done
[ 2586.349570] TRACE 1 dev->mdiobus->id -964161520
[ 2586.354204] lan78xx: Remote wakeup capability is enabled
[ 2586.359523] [DEBUG1] the mdiio value is 0000000053e716ae
[ 2586.359529] [DEBUG2] the mdiio value is lan78xx-mdio
[ 2586.364844] [DEBUG3] the mdiio value is 2
[ 2586.370070] TRACE 1 phydev -972208128
[ 2586.377747] TRACE 1 phydev phy_id 0
[ 2586.381239] TRACE 1 phydev drv 0
[ 2586.384470] lan78xx 3-1.2:1.0 (unnamed net_device) (uninitialized): no PHY driver found
[ 2586.392483] lan78xx 3-1.2:1.0 (unnamed net_device) (uninitialized): lan7801: PHY Init Failed
[ 2586.401482] lan78xx: probe of 3-1.2:1.0 failed with error -5

I have added debugging information to trace the issue, and it appears that the phydev pointer is not being initialized properly, resulting in the PHY driver not being detected. Request: Could you please provide guidance or any known solutions for this issue? Specifically, I am seeking advice on: Proper configuration for the LAN7801 PHY driver. Any additional kernel configurations or patches that might be required. Known compatibility or issues with KSZ9897 on kernel version 5.15.

I am trying to set up a GIT server in my LAN & use it with my Android phone through Termux. My PC runs Fedora Silverblue 40. Some tracelogs: * On my PC (all as user git):

$> ip addr show wlp5s0 | grep "inet " | awk '{print $2}' | cut -d '/' -f1
192.168.245.11
$> systemctl list-units | grep sshd.service
	sshd.service	loaded active running	OpenSSH server daemon
$> cat ~/.ssh/authorized_keys
ssh-ed25519 AAAAC3N[...]KBoG user@lan
$> ls -alps ~/.ssh/
total 4
0 drwx------. 1 git git  30 07-04 12:32 ./
0 drwx------. 1 git git 172 07-04 14:41 ../
4 -rw-------. 1 git git  92 07-04 13:07 authorized_keys
$> ls -alps ~/myrepo/user/
total 0
0 drwxr-xr-x. 1 git git 10 07-04 14:05 ./
0 drwxr-xr-x. 1 git git 12 07-04 14:05 ../
0 drwxr-xr-x. 1 git git 16 07-04 14:40 Notes/
$> ls -alps ~/myrepo/user/Notes/
total 4
0 drwxr-xr-x. 1 git git  16 07-04 14:40 ./
0 drwxr-xr-x. 1 git git  10 07-04 14:05 ../
0 drwxr-xr-x. 1 git git 144 07-05 16:34 .git/
4 -rw-r--r--. 1 git git   2 07-04 14:40 init
$> cd ~/myrepo/tsilvs/Notes/ && git status && cd ~
On branch main
nothing to commit, working tree clean
$> tail -n 4 ~/.bashrc
# Modified part
## Shell Session Start Message
CUR_TTY="$(tty)"
[ "$CUR_TTY" != "$SSH_TTY" ] && echo -e "Hello, $(whoami)!\n"

* On my Android device in Termux:

~ $ cat ~/.bashrc
eval "$(ssh-agent -s)"
ssh-add ~/.ssh/user.lan.001
~ $ eval "$(ssh-agent -s)"
Agent pid 6236
~ $ ssh-add .ssh/user.lan.001
Identity added: .ssh/user.lan.001 (user@lan)
~ $ cat .ssh/user.lan.001.pub
ssh-ed25519 AAAAC3N[...]KBoG user@lan
~ $ ssh-keygen -y -f .ssh/user.lan.001
ssh-ed25519 AAAAC3N[...]KBoG user@lan
~ $ ls -l .ssh/user.lan.001
-rw------- 1 u0_a196 u0_a196 399 Jul  4 14:03 .ssh/user.lan.001
~ $ ssh git@192.168.245.11 git-receive-pack /var/home/git/myrepo/user/Notes
00b1e1bbbef5f1220e0dc19be67fc2b6e66c5c5cb4dc refs/heads/mainreport-status report-status-v2 delete-refs side-band-64k quiet atomic ofs-delta object-format=sha1 agent=git/2.44.0
0000^C~ $                                              
~ $ git clone git@192.168.245.11:/var/home/git/myrepo/user/Notes
Cloning into 'Notes'...
fatal: protocol error: bad line length character: ?[47
fatal: the remote end hung up unexpectedly
~ $ ssh git@192.168.245.11
Last login: Sat Jul  6 12:47:58 2024
git@fed-001:~$>
~ $ ssh git@192.168.245.11 true
Hello, git!

Everything seems to be configured properly. For example, SSH sessions work perfectly fine. Why does the git clone terminate with an error?

If I install Windows on a computer, and plug it into my LAN, I can immediately ping it by name from any other computer. If I install MacOS on a Mac, and plug it into my LAN, I can immediately ping it by name from any other computer. If I install Linux on a computer, and plug it into my LAN......depending on the particular flavour of Linux, and what phase of the moon we're on, and whether or not I sacrificed a goat in a ceremonial circle at midnight before installing......I *may* be able to ping it by name, or I may not. The Internet is [full](https://unix.stackexchange.com/questions/323924/cant-ping-to-another-linux-machine-by-hostname) [of](https://unix.stackexchange.com/questions/225315/my-linux-pc-not-pingable-using-hostname) [forum](https://www.linuxquestions.org/questions/red-hat-31/ping-works-with-ip-address-but-fails-if-i-use-hostname-os-is-red-hat-server-6-2-a-948745/) [posts](https://www.linuxquestions.org/questions/linux-newbie-8/not-able-to-ping-hostname-4175615966/) [asking](https://www.linuxquestions.org/questions/linux-newbie-8/i-can-ping-ip-but-not-hostname-4175624845/) [this](https://www.linuxquestions.org/questions/linux-networking-3/can%27t-ping-domain-name-but-can-ping-ip-address-331508/) [exact](https://www.linuxquestions.org/questions/linux-networking-3/can%27t-ping-linux-machine-by-hostname-47268/) [question](https://askubuntu.com/questions/1311363/i-cant-ping-by-hostname-ubuntu-server) . And the Internet is full of answers like "go into your router's settings and add a DNS entry" or "edit the hosts file on every computer and add a line for the new computer". No. Clearly the mechanism exists for automatic configuration, so I want to use that. **My question is, therefore:** What package(s) can I install or configure on Linux – Debian, Alpine, or whatever else I choose to run – that will automatically register the machine's hostname with my router, like happens naturally with Windows and Mac without any user intervention? It must be possible. Some answers suggest avahi-daemon, but I installed and configured it and it still does not work. My own experiences suggest that samba will do it; but I don't want to open up that security hole. I assume that during the installation of samba it also drags a bunch of other stuff in, one part of which actually does the DNS fix....maybe?

I cannot get this one rule working right. My interfaces:

#WAN
auto wan0
iface wan0 inet dhcp

#LAN
auto lan0.7
iface lan0.7 inet static
    address 172.17.7.1
    netmask 255.255.255.0
    vlan-raw-device lan0

#DMZ
auto lan0.17
iface lan0.17 inet static
    address 172.17.17.1
    netmask 255.255.255.0
    vlan-raw-device lan0

The iptables rule I am having trouble with: iptables -A FORWARD -i lan0.17 -o lan0.7 -j DROP The goal here is to block DMZ traffic to LAN, but to allow it the other way around.  The rule above cuts LAN to DMZ too.  What am I doing wrong here? Output of iptables -nvL: Chain INPUT (policy ACCEPT 578 packets, 70339 bytes) pkts bytes target prot opt in out source destination Chain FORWARD (policy ACCEPT 2062 packets, 173K bytes) pkts bytes target prot opt in out source destination 164 13776 DROP 0 -- lan0.17 lan0.7 0.0.0.0/0 0.0.0.0/0 Chain OUTPUT (policy ACCEPT 402 packets, 33334 bytes) pkts bytes target prot opt in out source destination

I'm running Linux Mint 17.3 on my laptop. When docked, I'm connected via Ethernet, but when I undock, I'd like not to break my ssh sessions, ongoing downloads, etc., and to use the same IP address on the Wi-Fi adapter, so that still appears the same to other machines on my network. Bonding in mode 1, active backup, sounds exactly like what I want. I've found a number of resources online about how to set it up, but network configuration seems to vary quite a bit between distributions and even between different versions of each distribution, so that the steps for this vary quite a bit. What's more, most of the instructions I've found rely on static configuration, like hardcoding network addresses and even WPA passwords into /etc/network/interfaces. I take my laptop to other networks, so I rely on Network Manager to store network configuration. By googling "bond eth0 wlan0", I found a sample /etc/networking/interfaces file that more or less works, but I apparently have to disable Network Manager to keep it from doing weird things with my routing table. And while the bond is active, I can't seem to use the Network Manager applet to change Wi-Fi networks. Network Manager 0.9.8 supports bonded interfaces, but only for Ethernet and InfiniBand connections, not for Wi-Fi. Is there a way to bond Ethernet and Wi-Fi connections that's compatible with Network Manager?

I have two network interfaces on a client PC, one wired, one wireless. The wired is connected directly to a server PC running DHCP, which gives the client PC a 10.0... address. The client PC also connects to a wireless router, which gives it a 192.168... address. This was all set up and detected automatically by NetworkManager. I am able to ping the server PC and wireless router. The problem is I want to use the wired connection as a LAN only, and the wireless for WAN access to the wider Internet. But NetworkManager thinks the opposite, and tries to use the LAN to go to the outside Internet. If I unplug the cable it correctly uses wireless. But I'd like to have them both connected at the same time. I'm running Debian unstable if that matters. Is there some way to configure this?

**LAN not working on my Pop OS.** The wifi still works though, it's been a day since this happened. I changed ports and all of the cable and the cable works for others as well but not on my laptop l.

I'm managing a router running Linux 3.10.87-rt80-Cavium-Octeon On the router's GUI, there's a "Switch ports" page where I can see all ethernet ports (4 LAN - 2 WAN) and their corresponding link negotiation info. However there's nowhere I can find which MAC address is connected to each physical port on the router. I've googled and searched here to see if there was a linux command that could achieve this but could not find anything. Any help is much appreciated.

I want to redirect all traffic from my apps and programs (including those that do not support proxy or VPNs in their app configuration) to a local HTTP/SOCKS proxy server, which will then redirect the traffic to an online proxy server. I created the following network topology: However, I want to avoid creating a loop, where the local proxy server redirects traffic to the redirector, which then redirects it back to the local proxy server. Network Topology to Avoid:

I used to be able to ssh user@hostname.local between machines on my LAN but it is no longer working. I can ssh using the IP of course, but it's DHCP so it may change from time to time. Both machines run Debian 9.12, one is a VM in a Windows host, but still, it DID work ; I haven't fooled around with the config files, just regular updates.

ping hostname.local
ping: hostname.local: Name or service not known

(it might not be exactly that message as I translate from French)

ssh hostname.local
ssh: Could not resolve hostname hostname.local: Name or service not known

(ssh outputs in English) From avahi.org : > Avahi is a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite I've looked into /etc/resolv.conf, /etc/avahi/avahi-daemon.conf, /etc/nsswitch.conf but it's standard out-of-the-box config. /etc/resolv.conf (reset by network-manager each time it starts)

# Generated by NetworkManager
search lan
nameserver xx.xx.xx.xx # DNS IPs obtained from DHCP
nameserver xx.xx.xx.xx

man resolv.conf says that the search list contains only the local domain name by default (something like that, I translated from man page in French) ; shouldn't it be localinstead of lan ? I tried to change it and ping or ssh another host on my lan right away (without restarting network-manager), it didn't work. And when I restart network-manager, it rewrites /etc/resolv.conf and sets search lan. /etc/nsswitch.conf (default, I haven't made any change)

# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the glibc-doc-reference' and info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.

passwd:         compat
group:          compat
shadow:         compat
gshadow:        files

hosts:          files mdns4_minimal [NOTFOUND=return] dns myhostname
networks:       files

protocols:      db files
services:       db files
ethers:         db files
rpc:            db files

netgroup:       nis

I've tried to discover hosts and services with avahi-browse and nbtscan, which rely on avahi (zeroconf / Bonjour), but they seem to find only the host on which they run. (I know this is a possible duplicate of other questions, but I didn't find any answer and I don't have enough reputation to do anything)

I have a desktop with windows 10 on it, and I have another desktop with FreeBSD on it. No virtualization. I have shared some folders on Win desktop, which I can access on LAN with other Win10 laptops. But I am unable to access these folders from freebsd desktop, how can I do it? I went through older threads, but none of the solutions worked. All of them are outdated. The samba port of freebsd has been deleted https://www.freshports.org/net/samba

I'm using Fedora 37 on a desktop computer. More detailed system info at the end of the question. The system randomly loses connectivity (shows a yellow excalamation mark with "limited connecivity" message) on the wired connection (wireless keeps working). Disconnecting and reconnecting the wired network does not fix that. Only restart fixes that. - **Question 1**: How can I see the logs that show why this happens? - **Question 2**: Is there a way to fix this without a full restart? #### System info:

Operating System: Fedora Linux 37
KDE Plasma Version: 5.26.4
KDE Frameworks Version: 5.101.0
Qt Version: 5.15.7
Kernel Version: 6.0.12-300.fc37.x86_64 (64-bit)
Graphics Platform: X11
Processors: 32 × AMD Ryzen 9 7950X 16-Core Processor
Memory: 30.5 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 4090/PCIe/SSE2
Manufacturer: ASUS

Motherboard is: ROG STRIX X670E-E GAMING WIFI

I am setting up CI environment where I have two subnets connected by two peered bird routers. My current ipv4 config on one of the routers is as follows:

protocol device {
}

protocol direct {
  interface "eth0";
  interface "eth1";
}

protocol kernel {
  import none;
  export all;
}

protocol bgp {
  import all;
  export all;

  local    10.100.0.9 as 9;
  neighbor 10.100.0.7 as 7;
}

This and the other router are connected over 10.100.0.0/24. LAN instances connect to this router over 10.9.0.0/24. Currently, when I send LAN ethernet packets from e.g. 10.9.0.71 to 10.9.0.72, and the ethernet dst is router's MAC then the packet is delivered to LAN server. What I would like to achieve for LAN packets is: * when dst MAC is router's MAC then the packet does not reach the destination, * when dst MAC is destination server's MAC then the packet reaches that destination, just as it does now. I don't know very much about routing and bird documentation is rather targeted to experienced users. So far I tried using filters and blackholed static routes, but it was more of a guesswork and none of it worked.

I have a small cluster (all nodes run Debian 10) and need to remove the internet connections of all slave nodes. The internet cable connection connects to a computer that acts as a firewall, then, that computer sources a switch. All the cluster computers are connected to the switch. The firewall computer redirects all connections to the master node which is in the switch. The connection between nodes and the cluster is done via ssh. The internet provider changed its policy and now having all those computers connected to the same port is no longer possible. Then, what I want to do is to remove the internet access of all the nodes but keep the connections in the local network. Having internet access in only one node (the master node) is enough. I have tried many different solutions I found in forums and in the internet. Most of them suggest changing or removing the default gateway. This doesn't work because then the node becomes inaccessible from the other nodes. If someone knows how to do this I will appreciate it very much. EDIT: The masking address for the external connection is 168.176. Internally, the connection between nodes starts with 192.168. Basically, each PC goes to a port on the switch. 192.168.1.100, 192.168.1.101, 192.168.1.102, etc. You can log in to the cluster via ssh to the master and then for the type of work we use the cluster for, you need to be able to ssh to the other nodes.

I'm new to SSH and ufw and would like to understand why one type of rule works between two Linux Mint computers on the same home LAN but another does not seem to work. I just wanted to allow one computer to SSH into the other. To start with I checked that it does work if both firewalls are disabled and I can also see that SSH is using the default port 22. Then, using the following example local IP addresses 10.0.0.2 primary machine - where I want to be sitting and typing in the eventual SSH session 10.0.0.7 remote machine - the one that I'm logging into remotely **ATTEMPT #1** I set up this rule on the remote machine and left the firewall on the primary machine disabled: sudo ufw allow from 10.0.0.2 proto tcp to any port 22 but without luck (i.e. SSH times out). **ATTEMPT #2** I then deleted that rule and tried being even more specific - I entered a rule through gufw with "sudo ufw status numbered" showed as To Action From -- ------ ---- [ 1] 10.0.0.7 22 ALLOW IN 10.0.0.2 22 also with no SSH access. **ATTEMPT #3** Finally I reset it again and instead used sudo ufw allow 22/tcp and this finally allowed SSH access. It also works if I re-enable the primary machine's firewall using the default home setting. QUESTION 1 So, I get it that the last rule attempt is much less restrictive but I don't see what was wrong with either of the first two attempts. QUESTION 2 Also, in my travels accross the web I've noticed that attempt 3 is quite commonly advised. In my beginners worldview it seems to me that something that only does exactly what I want and no more should obviously be safer so I don't understand why such a wide open approach is recommended.

In dhcpconf.conf file I have set noipv6 in the section of interface used for the connection, in past this apparently worked, now the device has assigned both IPv4 and IPv6 as I can se from inet6 address in ifconfig output, and if I try to connect to it from another device in the network using IPv6, it connects correctly with the IPv6 assigned normally. How I can make sure only IPv4 is assigned?