Cannot access website from another computer on the same network - firewall

This is odd to me:
I have jupyter notebook installed on a vm machine, it is working fine from localhost:8888/tree. The vm machine has an address of 192.168.112.150, I assume the site can be accessed from my desktop browser by typing: 192.168.112.150:8888/tree
I receive error saying:
This site can’t be reached
192.168.112.150 took too long to respond.
I checked firewall settings on my desktop, it's opened; on the vm machine, I made some adjustment, here is the settings:
I have no problem ping the vm machine from my desktop
Can anyone enlighten me how to fix the issue? Thank you very much.
Updated: I receive this error message when I ran it with --ip=0.0.0.0

By default, the Jupyter Notebook only listens to incoming connections on localhost--it has zero permission checking or built-in safeguards otherwise. Adding --ip=* to the end of the command will have it listen on all of your network interfaces.

Related

Cant hit Node-Red web page on Vultr Machine

I have just finished setting up Node-red on the a cloud machine hosted with vultr ( Ubuntu 20.04 x64 ) and I am wanting to be able to hit the Node-Red web page but I am failing to do so.
I have setup WireGuard so I can VPN into the machine
I am able to ping the servers Local IP address from my Windows PC
But I am still unable to hit the Node-Red Web Page
Even though Node-Red is running
I am fairly new to working with cloud machines so any help would be highly appreciated.
I'm going to guess that you haven't opened port 1880 for the server.
This could be in one of 2 places
Vultr appear to have their own firewall which you will need to ensure a suitable rule to allow TCP traffice on port 1880 exists. How to configure the firewall appears to be documented here https://www.vultr.com/docs/vultr-firewall-quickstart-guide/
You will need to make sure that the port is open in the Ubuntu Firewall as well. Running sudo ufw allow 1880/tcp should do this.

How can I link a C websocket server running on AWS Linux with the client on a virtual machine locally?

I recently wrote an echoserver / echoclient program in C for the online class I'm taking (Graduate Introduction to Operating Systems, here). I was able to complete it with the help of (and modification from Beej's Network guide (here). I can run it just fine on my Ubuntu 20.04 virtual machine, running on my Windows 10 laptop. However, I'm trying to run the echoserver on an AWS Linux instance and the echoclient from the Ubuntu VM, as my end goal is building a client program that has a central server data repository. However, I'm running into issues where I start the echoserver C code on the AWS EC2 instance through SSH-ing by PuTTy, then I run the echoclient on the Ubuntu VM, but it can't connect (the error I receive on the client side is that it failed the connect phase of the socket call). I've tried the following steps:
Editing the inbound rules of the security configuration of the EC2 instance to allow for 'All TCP' connections from the IP address that comes up when I run curl ifconfig.me on my Ubuntu machine
Changing the network setting of my Ubuntu VM from NAT to Bridged Network
Testing port access by telnet <AWS Public IP> <PortNo> - which led to "Connection Refused" error
Ensuring that my outgoing ports aren't blocked by following these instructions
I've looked through the AWS pages (here) as well as multiple developer / SO threads (best one I found so far here) and I just can't seem to figure out out. If anyone could help me out, I'd really appreciate it. I'm happy to post my server & client code if that would be of help.
Figured it out: was missing the following line of code in my server.
hints.ai_flags = AI_PASSIVE;

Localhost not working and running on different network?

Overview
Win 10 pro, 64bit
static-server works from localhost
All other node.js servers stop working on localhost,127.0.0.1 and only works on 172.16.xxx.xxx host
From the source I can see that static-server host is 0.0.0.0 which is the same as mine. I run my server on 0.0.0.0 https://nodejs.org/api/net.html#net_server_listen_port_host_backlog_callback
All this happened suddenly on my windows machine and on several web apps with webpack. I installed windows again and the issue persists.
I use WebpackDevServer with host : 0.0.0.0
Details
I'm running on a brand new win 10 with some vpn installed.
So I have these 3 apps
webpack-app on host 0.0.0.0:9080
static-server on port 9080 (should be localhost as well)
webpack-app with react-create-app on port 3000
I start the webpack-app on port 9080 and I go to the browser and says "This site can’t be reached,localhost refused to connect." (I'm 100% sure is running on 9080 because all my webpack apps stop working at once)
I now start static-server and runs on port 9080, doesn't complain at all! Now I go to the browser and it opens the page on port 9080.
So now I think I'm running on 2 different networks. Here is how it looks in windows:
So now I look if somebody is listening to the port 9080 and I see this:
I turn off the static-server and it disappears. Means that the static-server correctly shows up there.
Also there is no other node.exe process over there. So where did my webpack-app ended up?
Now after some times something popups there on port 3000
Not sure why there are so many on the same port, I go to that url and it works. But doesn't work from localhost:3000.
What is going on? why it doesnt work from localhost anymore?
If you use the Windows Subsystem for Linux, especially WSL2, keep in mind that it runs in a Hyper-V virtual machine with a virtual NIC. In other words, it creates its own virtual network.
According to the WSL2 FAQs:
the new architecture uses virtualized networking components. This
means that in initial preview builds WSL 2 will behave more similarly
to a virtual machine, e.g: WSL 2 will have a different IP address than
the host machine. We are committed to making WSL 2 feel the same as
WSL 1, and that includes improving our networking story.
As a result, the development server will run at a different address than 127.0.0.1 (aka localhost). This is why a connection refused error is returned when calling localhost from the browser.
Here is a possible solution, as suggested by Microsoft.
Ran into the same issues as above. Cleared my browser data and cache, it worked like a charm!!
So very strangely after a few restarts it just works. My node.js server listens on 0.0.0.0 instead of 172.xxx.xxx.xxx. I'm really confused as why it works now and why was not working before. If somebody can figure out would be wonderful. Thanks everybody for the help.
Edit: Happened again and I fixed like this: I disabled all my docker and expressvpn apps to start on windows start and restarted my pc, now works.
Edit 2: Happened again and I fixed by closing express vpn and disabling my wifi. I only use the wired Ethernet cable. No need to restart this time.
I think something is going on with my windows machine. Not sure why there are to networks.

Problems connecting two laptops using a cross-over cable?

I connected two laptops using a cross-over cable. My IP Address is 192.168.1.1 and the other IP Address is 192.168.1.16. We both are able to ping each other and the reply is perfect. There is no loss of packets.
The problem is I shared a file and the other system is not able to open my IP Address using the run command. Even I am not able to open my Shared folder by giving in the run (\\192.168.1.1). A dialogue box with the message \\192.168.1.1, The Network Path was not found opens each time we try this.
But I am able to open his shared folder by giving in run command (\\192.168.1.16). I closed all the firewall services in my system. But still my system is not able to respond. Also we are not able to use remote desktop connection.
Can anyone please help me in solving this?
Additional Details: I use Windows XP and the other machine uses Windows 7. We both are in the same work group.
Here are some steps to solve your problem:
Did you set the static IP by yourself or that come automatically?
If yes then please go and set the IP manually
Then share the file and put the permission of that file to Maximum (If you believe your partner)
Then power down the firewall or antivirus for some moments (say 10 minutes)
Now try to connect using the \192.xxx.xxx.xxx method using the Run window
If the 5th step is not working, then try disabling and reenabling the LAN card, then try the 5th step again.
Hope that solved your problem.
Remote Desktop needs to be explicitly enabled. Right click on "My computer", go to properties and look at the remote settings tab.
I advice you to use Radio Access Point to connect both windows 7 and windowsXP. I think this is best choice of troubleshoting jaringan. why?
Because I already do anything to connect both Operating System but can't solve that problem.

andlinux slirp network failed

I have installed andlinux Beta 2 on my WinXP. Everything works fine until last night, I don't recall that I ever changed anything on network configuration or andlinux setup, the network stop working inside andlinux. With that said, I mean open a KDE console, I do "ping yahoo.com", I see DNS is resolved correctly, however, no response at all.
My andlinux is startup as a WinXP service. Open windows task manager I can see following services are up and running:colinux-daemon.exe colinux-net-daemon.exe colinux-slirp-net-daemon.exe
On andlinux side, there are two network interface eth0 and eth1. eth1 is configured to communicate with local WinXP. I configured it to use samba to access windows directories, no problem. From WinXP side, I can use ssh to login into andlinux box via eth1 IP address.
eth0 is configured as slirp, no port forwarding. eth0 has IP=10.0.2.15, default gateway is 10.0.2.2, netmask=255.255.255.0; These are configured in /etc/network/interfaces. DNS is 10.0.2.3, which as I just mentioned resolve yahoo.com correctly.
On the windows side, internet works fine. I disabled firewall on all network interface. I rebooted my laptop, no luck. I searched over inet, seem no one has this problem. People say network is done if they kill the colinux-slirp-net-daemon. What frustrated me is that this whole thing worked well, but for no reason it's broken all the sudden. Anyone has experience on this issue, please help, appreciate!
I thought I had the same problem, but then found my andLinux system's network connectivity was actually working fine, and that several things made it difficult to tell what was going on.
Test I did to validate connectivity: wget www.yahoo.com
Behavior I observed that made troubleshooting difficult:
Pings from andLinux - not all hosts will respond to pings from the andLinux OS (ie Ubuntu, not the Host Windows OS). According to my packet captures the pings appear as UDP pings instead of ICMP pings once they leave the host OS's adapter. The major IPs/hosts (like yahoo, google, 4.2.2.2 etc.) on the internet I usually ping to test connectivity currently don't respond to these type of pings.
Traceroutes from andLinux - even when successful, these never show more than 2 hops when done from the andLinux OS. If successful, both hops show 10.0.2.2. If unsuccessful, the second hop just times out. Not sure why, I'm sure there is an explanation.
Packet captures - at the host OS level, the capture (eg wireshark) must be done on the physical interface the traffic is going over. I was initially capturing on the TAP-Win32 Adapter but this only showed X Window traffic.
Installed apt sources URLs no longer valid - Ubuntu 9.04 is long out of support by now, so the URLs in the apt sources.list file didn't exist anymore. This is what got me thrown off in the first place, because I didn't troubleshoot this specifically and just tried to test my internet connectivity first, then got confused by the ping and traceroute behavior seen above. Changed http://us.archive.ubuntu.com/ubuntu to http://old-releases.ubuntu.com/ubuntu/ in sources.list and was good to go.

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