Ethernet connection setup fails

I have been working with a robot via ethernet connection for the past few weeks. Everything worked fine until today.

The robot (UR5) has a modbus/internet port with a ethernet cable connected to my laptop (latest version Ubuntu). The setup settings of the robot are:

  • ip address: 192.168.1.151
  • subnet mask: 255.255.255.0
  • default gateway: 192.168.1.1
  • preferred DNS server: 192.168.1.1
  • alternative DNS server: 0.0.0.0

When I try to ping the ip address of the robot I get:

$   ping 192.168.1.151 PING 192.168.1.151 (192.168.1.151) 56(84) bytes of data. From 192.26.169.225 icmp_seq=1 Packet filtered ^C --- 192.168.1.151 ping statistics --- 230 packets transmitted, 0 received, +1 errors, 100% packet loss, time 234474ms 

From

ipconfig

I get:

enp0s25   Link encap:Ethernet  HWaddr 28:80:23:d6:28:d5             inet6 addr: fe80::2a8d:3ae1:e449:1bc1/64 Scope:Link           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1           RX packets:130 errors:0 dropped:0 overruns:0 frame:0           TX packets:1258 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:43570 (43.5 KB)  TX bytes:254399 (254.3 KB)           Interrupt:20 Memory:d0700000-d0720000   lo        Link encap:Local Loopback             inet addr:127.0.0.1  Mask:255.0.0.0           inet6 addr: ::1/128 Scope:Host           UP LOOPBACK RUNNING  MTU:65536  Metric:1           RX packets:8886 errors:0 dropped:0 overruns:0 frame:0           TX packets:8886 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:1239779 (1.2 MB)  TX bytes:1239779 (1.2 MB)  wlo1      Link encap:Ethernet  HWaddr 80:86:f2:69:4d:08             inet addr:10.10.6.78  Bcast:10.10.7.255  Mask:255.255.252.0           inet6 addr: fe80::202:cd06:772f:14fd/64 Scope:Link           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1           RX packets:84136 errors:0 dropped:0 overruns:0 frame:0           TX packets:29266 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:107879600 (107.8 MB)  TX bytes:5012810 (5.0 MB) 

How come the connection is suddenly lost?

Ubuntu 18.04 and ethernet connection

I installed Ubuntu 18.04 today but I can’t use the internet.

But Ubuntu 18.04 does recognize that the ethernet cable is connected. When I go to the Settings – Network, it says ‘Ethernet (enp3s0) Connected – 100Mb/s’ and ‘Ethernet (enp4s0) Cable unplugged’.

I know people have asked questions like this with what the ‘ifconfig’ command printed in cmd. However, I can’t download ifconfig since there is not internet connection in the first place. In this case, is the problem a hardware problem?

Private networking with direct crossover Ethernet cable failing

I have two home computers. One is running 16.04 and the other had 14.04 installed. The 14.04 machine has since been upgraded to 18.04.

When it was 14.04 and 16.04, connecting the two computers directly with an Ethernet cable was a straightforward matter. I’d set static IPs via an dialog like the one below and I’d be ready.

enter image description here

It’s not as straightforward with 18.04, apparently. Before my attempt to pair the two computers with the cable, I was using a Wired connection 1 to connect to the Internet on the 18.04 machine — I’d just plug it in and I’d be online in seconds. After the pairing attempt, not only were the two machines not seeing each other on the private network as I was expecting, but Wired connection 1 is no longer connecting to the Internet when I switch to it.

Here is the dialog I’m struggling with on 18.04. As can be seen, it’s different from the first image which is the dialog on both 14.04 and 16.04.

enter image description here

So how do I do it?

Ubuntu 18.04.2 Ethernet Bonding

This question is quite unique and different from other guides and documentations out there.

I don’t see any point in bonding two NICs that are connected to the same source because if the source goes down, then bond0 will be rendered useless.

What I’m doing is, I’m trying to bond two NICs with each one having a different source (ISP) so it’s obvious that each one of them will have a different IP address, different gateway etc.

My question is: following almost “every guide” on the internet shows that bond0 needs to be static and i need to set an IP address for it as well as a gateway. How on earth am I supposed to set a static IP address with a static gateway FOR TWO DIFFERENT SOURCEs?

Can someone please explain this?

let’s say NIC1 have: IP_ADDRESS=192.168.1.3 GATEWAY=192.168.1.1

NIC2 have: IP_ADDRESS=192.168.2.14 GATEWAY=192.168.2.1

BOND0 should be static based on what? What am I supposed to write in /etc/network/interfaces

Can connect to server on the university network with ethernet but not with wifi

In my lab, we set a dell server with the idea to connect via wifi to it. The server is located on the university and connect to the Internet with ethernet, using an static ip.

The server is running Linux server and i’m using windows 10 on my laptop. I set up to xrdp remote desktop and to ssh to connect to it. I can be connected and use the server when my laptopis connected with ethernet, but it is not possible with wifi, which was the main point of the server. This is the same for xrdp and ssh, i can connect with ethernet but not with wifi.

I’m really lost since this is the first time that I set up a remote connection. I have not clue what the problem could be.

Thanks for your answers!

PS: The network is eduroam.

Is it practical to have several subnets under a ethernet port for a dhcp configuration?

Does it make any sense to set several subnets on a ethernet port of DHCP server. The configuration on dhcpd.conf is listed below and the server has no complain, but it is doubtful:

subnet 192.168.10.0 netmask 255.255.255.0 { #ethernet port enp5s0; range 192.168.10.100 192.168.10.120; range 192.168.10.200 192.168.10.220; option domain-name-servers 1.1.1.1, 2.2.2.2; option routers 192.168.10.1; default-lease-time 86400; max-lease-time 259200; } subnet 192.168.30.0 netmask 255.255.255.0 { #ethernet port enp5s0; range 192.168.30.100 192.168.30.120; range 192.168.30.200 192.168.30.220; option domain-name-servers 1.1.1.1, 2.2.2.2; option routers 192.168.30.1; default-lease-time 86400; max-lease-time 259200; } subnet 192.168.40.0 netmask 255.255.255.0 { #ethernet port enp7s0; range 192.168.40.100 192.168.40.120; range 192.168.40.200 192.168.40.220; option domain-name-servers 1.1.1.1, 2.2.2.2; option routers 192.168.40.1; default-lease-time 86400; max-lease-time 259200; }

Sharing PC WiFi internet to USB Ethernet device (raspberry Zero USB connected)

I connected my Pi Zero to my PC ( Linux LMDE 3 Cindy) via USB port successfully, SO i want to connect to internet via my laptop which is connected to internet by its WIFI.

I found this instruction or this question via raspberrypi.stackexchange but those are working for window or MAC OS,but i don’t find it for Linux!!!!

SO i need the similar instruction for enabling sharing my internet via USB enp0s20f0u1 device (PI Zero) in Linux. for example in windows we need to :

In the WiFi Properties window, click on the “Sharing” tab : similar to this photo:

i could assist one IP (192.168.7.2) for my raspberry by running this code in my raspberry based this instructions :

sudo nano /etc/network/interfaces allow-hotplug wlan1 iface wlan1 inet manual    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf  allow-hotplug usb0 iface usb0 inet static         address 192.168.7.2         netmask 255.255.255.0         network 192.168.7.0         broadcast 192.168.7.255         gateway 192.168.7.1 

I have this (sudo ifconfig) in my Linux:

 enp0s20f0u2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500         inet 169.254.27.126  netmask 255.255.0.0  broadcast 169.254.255.255         inet6 fe80::cff5:f703:7327:dd9  prefixlen 64  scopeid 0x20<link>         ether 6e:2f:15:92:bd:a8  txqueuelen 1000  (Ethernet)         RX packets 2936  bytes 244294 (238.5 KiB)         RX errors 0  dropped 0  overruns 0  frame 0         TX packets 2113  bytes 174942 (170.8 KiB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0    wlp2s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500         inet 192.168.1.105  netmask 255.255.255.0  broadcast 192.168.1.255         inet6 fe80::373d:1b7f:5b9e:8ddc  prefixlen 64  scopeid 0x20<link>         ether c8:3d:d4:3c:23:63  txqueuelen 1000  (Ethernet)         RX packets 33305  bytes 31322783 (29.8 MiB)         RX errors 0  dropped 0  overruns 0  frame 0         TX packets 26405  bytes 4264995 (4.0 MiB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0 

the enp0s20f0u2i2 is my Raspberry zero which is using IPV4 Link-local only method but i could change its IP to static IP like 192.168.7.2 as described above.

And in my raspberry:

pi@raspberrypi:~ $   ifconfig -a lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536         inet 127.0.0.1  netmask 255.0.0.0         inet6 ::1  prefixlen 128  scopeid 0x10<host>         loop  txqueuelen 1000  (Local Loopback)         RX packets 72  bytes 6840 (6.6 KiB)         RX errors 0  dropped 0  overruns 0  frame 0         TX packets 72  bytes 6840 (6.6 KiB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0  usb0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500         inet 169.254.183.232  netmask 255.255.0.0  broadcast 169.254.255.255         inet6 fe80::d7db:e53b:407d:8d65  prefixlen 64  scopeid 0x20<link>         ether ee:70:24:ba:2d:57  txqueuelen 1000  (Ethernet)         RX packets 182  bytes 28198 (27.5 KiB)         RX errors 0  dropped 0  overruns 0  frame 0         TX packets 172  bytes 15872 (15.5 KiB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0 

so when i do this site instruction I run this code in my Linux:

# Bring both interfaces into promiscuous mode sudo ip link set wlp2s0 promisc on 

and this code in my raspberry:

sudo ip link set usb0 promisc on 

when i run this code in my LINUX OS (laptop):

# Creating a new bridge interface sudo brctl addbr br0  # Set the forwarding delay to 0. # While this is not necessary, I learned that it help with faster configuration sudo brctl setfd br0 0 

SO when running next step (sudo brctl addif br0 wlp2s0 enp0s20f0u2) i get this error:

can't add wlp2s0 to bridge br0: Operation not supported 

so i doing this :sudo iw dev wlp2s0 set 4addr on from here to solve this bug, but i lose my internet connection :

so@notebook:~$   ping www.google.com ping: www.google.com: Name or service not known 

ans also lose my connection with my Raspberry zero (USB Ethernet).

SO what i must t to do to make a bridge for sharing my laptop internet with raspberry zero?

  • I have this kind of question in raspberrypi.stackexchange site and based on those comments,I asked this question here

Thanks a lot.

Multiple vpn clients sharing to multiple ethernet ports

I have a intel Atom mini pc that I will use to connect to internet (via wifi antenna). I will also configure two vpn clients on that pc connecting to servers in two different countries. The mini pc has two ethernet ports. I want to set it up to forward the country 1 vpn connection to a first wifi router and the country 2 connection to a second wifi router, by connecting the wan port of each router to one of the ethernet ports on my mini pc. I will then have two secured networks at home that directly go through the vpn’s in other countries (one is for Netflix).

I mainly do this to avoid the router vpn speed bottleneck caused by the lack of AES encryption hardware acceleration on consumer grade cheap routers. The Intel Atom will take care of all the encryption necessary.

Is this doable without digging deep into IP Tables? it not, where can I start?