I am ssh-ing onto a remote desktop. Since I have to connect over the internet, I have exposed the ssh port (22) on the remote side using ngrok, and everything is working great. I connect to the desktop using the command
ssh username#2.tcp.ngrok.io -p portno
where I get the portno from the remote side, when I start the ngrok service from the line that says
Forwarding tcp://2.tcp.ngrok.io:portno -> localhost:22
However, everytime I start a new ngrok session on the remote side, a new portno is generated. Now, unless I have a secondary connection open (typically using teamviewer), I would not be able to know what that port number is.
How can I start the ngrok service with a fixed portno. This is because I want to have the ngrok service on startup as I would have to restart my remote desktop a couple of times and still want to connect to the desktop using ssh.
Thanks.
You'll need to reserve a TCP address on ngrok, which will give you a fixed address.
To associate a tunnel with a reserved TCP address, you should include the remote-addr option in your ngrok config when starting the tunnel.
An example from the docs: ngrok tcp --region=us --remote-addr 1.tcp.ngrok.io:20301 22
Related
I was updating the ssh port of an Oracle Cloud Infrastructure machine
I changed /etc/ssh/sshd_config
The port was
#Port 22
I changed it to
Port 40531
Then
restarted the sshd service systemctl restart sshd
open the port on the OCI Web
however, now I cannot connect.
ssh -vvv -p 40531 -i ~/.ssh/vm.key opc#129.xxx.xxx.xxx
OpenSSH_8.2p1, OpenSSL 1.1.1e 17 Mar 2020
debug1: Reading configuration data /etc/ssh/ssh_config
debug2: resolve_canonicalize: hostname 129.xxx.xxx.xxx is address
debug2: ssh_connect_direct
debug1: Connecting to 129.xxx.xxx.xxx [129.xxx.xxx.xxx] port 40531.
debug1: connect to address 129.xxx.xxx.xxx port 40531: Connection timed out
ssh: connect to host 129.xxx.xxx.xxx port 40531: Connection timed out
I saw a Cloud Shell but I'm not sure if it can be used to connect to the machine to perform maintenance tasks
Is there a way to connect to the VM from the web oci interface to fix the ssh issues?
I used to use a VPS service that has a web console from which you can enter to fix problems like this
is there something like this in OCI?
Note:
SELinux was disabled on the machine
if you are about to do this on your machine, remember to update the SELinux configuration prior restart the sshd service or you will be locked out, another option is to disable SELinux totally (this is what I did)
The changes above described worked well, the only thing that was causing issues on my side
(I don't really know why) is that I was connected from a VPN
After I disconnected the VPN and tried to connected again it worked
Update:
I figured out why the ssh using a different port was not working. The VPN I use is a corporate VPN which has very strict inbound and outbound rules, The VPN outbound rules were blocked by the TCP on port 40xxx.
Update:
if you are struggling with a VM you can connect using the below instruction
Creating the Instance Console Connection
Before you can connect to the serial console or VNC console, you need to create the instance console connection.
To create the console connection for an instance
Open the navigation menu. Under Core Infrastructure, go to Compute and click Instances.
Click the instance that you're interested in.
Under Resources, click Console Connection.
Click Create Console Connection.
Upload the public key (.pub) portion for the SSH key. You can browse to a public key file on your computer or paste your public key into the text box.
Click Create Console Connection.
When the console connection has been created and is available, the state changes to Active.
Thanks to #bmuthuv for the info
You can connect to Serial Console of the VM where you could get access to GRUB Menu during a Reboot operation. You can subsequently use typical Linux commands to get to Shell from Grub. You can subsequently undo anything you would like to.
Serial Console connection can be created on OCI Web Console in the Instance's page.
I'm developing some webhook required direct access public domain to internal machine, thinking use SSH tunnel to forward data, or got alternative solution?
Hosting server & development machine are in same network
192.168.1.2/24 (Hosting server)
2nd machine is virtual mapping using forticlient firewall without static or dynamic IP in visible in hosting server, so is 1 way initial communication right now.
In this case possible to setup SSH tunnel forward all traffic from 192.168.1.2:80 to handle in development machine port 8080?
How to ssh syntax look like?
Thanks.
This could be done by setting up an SSH tunnel to the remote machine:
ssh -L localhost:80:localhost:8080 development-system
Every request to port 80 on the hosting-server is now forwarded to port 8080 on the development-system.
Please note, that the port 80 on the hosting-server could only be used, when you start the SSH command as root. Also note that the port 80 is only accessible from the hosting-server. To access the port 80 on the hosting-server from everywhere use the following:
ssh -L 80:localhost:8080 development-system
Be sure that you want that.
A good introduction to the topic could be found at
https://www.ssh.com/ssh/tunneling/example
https://unix.stackexchange.com/questions/115897/whats-ssh-port-forwarding-and-whats-the-difference-between-ssh-local-and-remot
I want to connect to a remote server (host1) that accessible only from it's private network.
Another server (host2) is accessible from the Internet.
I opened a tunnel to host2 using PuTTY and tested it's working with Firefox (also checked that I got different IP address).
How can I connect to host1 using the tunnel I created?
I tried to configure proxy (to the tunnel I created - localhost) in PuTTY but it's not working.
The error I got: "Server unexpectedly closed network connection"
Pay attention that the host is the computer name in the network.
You connect to the local tunnel end directly, no "proxy" setting is needed.
This typically means that you use "localhost" as a Host Name. And a port according to your tunnel configuration.
See my guide for tunneling SFTP/SCP session. It's for WinSCP, but just use PuTTY instead of WinSCP in section Connecting through the tunnel.
I SSH into my workstation, which is a mac running OS X Yosemite, daily. Unfortunately, I noticed a while back that enabling remote login into my machine has put it under the fire of many automated dictionary attacks trying to log in using the default port, 22.
To make my machine more secure, I changed the SSH port. To do so, I edited the /etc/services file, and changed the following two lines:
ssh 2123/udp # SSH Remote Login Protocol
ssh 2123/tcp # SSH Remote Login Protocol
That greatly reduced the number of dictionary attacks, but now when I try to SSH from my workstation to other machines, I always need to specify the port (which is usually port 22).
This is easy enough for most simple tasks, just specify the port when SSHing in:
ssh -p22 me#another.computer.com
It becomes a pain for more complicated tasks where specifying the port is not an option, but it can still be done by adding an entry in ~/.ssh/config:
Host github.com
Hostname ssh.github.com
Port 443
Between these two options, I could always connect to any machine I wanted to connect to. However, I'm now writing a script that will connect to machines that will have different IP addresses (and domain names), and there is no optional argument to specify the port number.
I have also been getting frustrated that it does not default to port 22 for outgoing connections, but I do not want to change my incoming port back to 22.
Is it possible to change the incoming SSH port, but still have the default outgoing SSH port? That is, can I only allow people to login to my workstation using port 2123, but when I try connecting to other machines, the default port it tries to use is port 22?
I'm running OS X 10.10.2 Yosemite.
Change the ssh port back in `/etc/services' - that sets the defined port for the ssh protocol.
Then change the port that sshd listens on. On OS-X this is more complicated than it need be. See https://serverfault.com/questions/18761/how-to-change-sshd-port-on-mac-os-x
I want to connect to remote amazon aws service(EC2 instance) , and I would like to be able to ssh to it from my laptop while using the campus provided network (which has cyberoam firewall). However, they have pretty much every port blocked and ssh won't work. Is there anything i can do? does ssh run through port 80? I don't really know what to do .
All it says is :
ssh_exchange_identification: read: Software caused connection abort
ssh works elsewhere.
You can set your SSH server to use port 80 (or 443 if 80 is used for a webserver). Just check the configuration file of your ssh server for more details!