Is it possible to use tunneling to connect to a ssh server via telnet? I'm using an API that can only telnet to a host, but that host will only accept ssh connections. If it is possible, what do I need to do to set that up?
Use netcat and ssh
$ nc -l -p 12345 -c "ssh someone#remotehost.com"
make sure that you have RSA auth setup, since you cannot enter a password.
i think what would work would be to run a telnet server on a local port on the host and use ssh to forward that locally where the api could connect to it; but that's just a bit silly
Related
My organisation makes us connect to our AWS environments using a "bastion" host so my openssl .ssh config file looks a bit like this:
Host bastion.*.c1.some.com
User bastionuser
ProxyCommand none
StrictHostKeyChecking no
ForwardAgent yes
Host *.c1.some.com 12.345.* 456.12.1.*
User awsuser
StrictHostKeyChecking no
ForwardAgent yes
ProxyCommand ~/.ssh/proxy_command.sh %h %p
I want to use an ssh client built into the CLion IDE to connect to my AWS environment but it does not support this kind of configuration.
Can I setup a port forward using openssl and then establish an ssh connection over that tunnel from within CLion?
I was able to setup a port forward using PuTTY and afterwards I was able to establish a second ssh connection over the port forward using Intellij. For some reason I couldn't establish the second ssh connection over the OpenSSH port forward, perhaps because the Git Bash environment is sandboxed or something?
Presumably this will also work with any other SSH client that doesn't support tunneling out of the box.
I have a requirement to tunnel NETCONF (typically TCP-22) connections over a jumphost, but for a dynamic host.
I understand I can do remote SSH tunneling for defined hosts, e.g.:
ssh -R 2201:jumphost:22 rtr1
ssh -R 2202:jumphost:22 rtr2
But I'd like to be able to connect to a dynamic host, by tunneling over a jumphost, something like:
ssh -R 2201:jumphost:22 *
And then to be able to make a NETCONF connection such as:
connect rtrN port 2201
Is this doable via SSH tunneling? I don't want to use dynamic SSH tunnels, as I'd have to specify a proxy port whenever I make the connection, which I can't really do when I make the connection.
I've actually figured out how to do this in case anyone is interested:
In SSH config file:
Host *.*
ProxyCommand ssh user#jump nc %h %p
Then anything you SSH to, will forward over the jump connection, then nc to the host.
Here's the thing. I'd like to access a remote host by ssh, and make a tunnel as a proxy. I did it on my windows computer with Putty. In putty, there is a "tunnels" options, add a dynamic tunnel would do the trick. That is, a (dynamic, that is in the putty's option, I don't really know what it means)tunnel at port 1111, and then I can access the internet though socks5 proxy 127.0.0.1:1111.
But now I want to make the tunnel on my openwrt router, 192.168.1.1, and access the proxy as 192.168.1.1:1111. I want to know how. There are two major question:
1.the proper command of ctl ssh to make a tunnel just as the putty did. I googled a few, but because of the 2nd question, I never know which one is correct.
2.how can I access the tunnel on the router though 192.168.1.1:1111. As I tried before with ss_local(another proxy program), I established a socks locally but it can never be accessed by my another LAN host. Are there some firewall things to do?
Does anyone know the answers? Thank you!
This is what I did to access remotely to my AP.
I used a SSH Reverse Tunnel to a remote server. Here I dump a simple script to achieve it.
key_ssh=/root/.ssh/id_rsa
user=root
ip='YOUR_SERVER_IP'
port='THE_PORT_YOU_WANT_TO_CONNECT_THROUGH'
#connect ssh
ssh -f -N -i $key_ssh -R 0.0.0.0:$port:localhost:22 $user#$ip
And in your remote server you type:
sudo su
ssh -p THE_PORT_YOU_WANT_TO_CONNECT_THROUGH localhost
You will be asked for the root password, type it and you're in.
I am running Ansible on my machine. And my machine does not have ssh access to the remote machine. Port 22 connection originating from local machine are blocked by the institute firewall. But I have access to a machine (ssh-tunnel), through which I can login to the remote machine. Now is there a way we can run ansible playbook from local machine on remote hosts.
In a way is it possible to make Ansible/ssh connect to the remote machine, via ssh-tunnel. But not exactly login to ssh-tunnel. The connection will pass through the tunnel.
Other way is I can install ansible on ssh-tunnel, but that is not the desired and run plays from there. But that would not be a desired solution.
Please let me know if this is possible.
There are two ways to achieve this without install the Ansible on the ssh-tunnel machine.
Solution#1:
Use these variables in your inventory:
[remote_machine]
remote ansible_ssh_host=127.0.0.1 ansible_ssh_port=2222 ansible_ssh_user='username' ansible_ssh_private_key_file='/home/user/private_key'
hope you understand above parameters, if need help please ask in comments
Solution#2:
Create ~/.ssh/config file and add the following parameters:
####### Access to the Private Server through ssh-tunnel/bastion ########
Host ssh-tunnel-server
HostName x.x.x.x
StrictHostKeyChecking no
User username
ForwardAgent yes
Host private-server
HostName y.y.y.y
StrictHostKeyChecking no
User username
ProxyCommand ssh -q ssh-tunnel-server nc -q0 %h %p
Hope that help you, if you need any help, feel free to ask
No request to install ansible on the jump and remote servers, ansible is ssh service only tool :-)
First make sure you can work it directly with SSH Tunnel.
On local machine (Local_A), you can login to Remote machine (Remote_B) via jump box (Jump_C).
login server Local_A
ssh -f user#remote_B -L 2000:Jump_C:22 -N
The other options are:
-f tells ssh to background itself after it authenticates, so you don't have to sit around running something on the remote server for the tunnel to remain alive.
-N says that you want an SSH connection, but you don't actually want to run any remote commands. If all you're creating is a tunnel, then including this option saves resources.
-L [bind_address:]port:host:hostport
Specifies that the given port on the local (client) host is to be forwarded to the given host and port on the remote side.
There will be a password challenge unless you have set up DSA or RSA keys for a passwordless login.
There are lots of documents teaching you how to do the ssh tunnel.
Then try below ansible command from Local_A:
ansible -vvvv remote_B -m shell -a 'hostname -f' --ssh-extra-args="-L 2000:Jump_C:22"
You should see the remote_B hostname. Let me know the result.
Let's say you can ssh into x.x.x.x from your local machine, and ssh into y.y.y.y from x.x.x.x, while y.y.y.y is the target of your ansible playbook.
inventory:
[target]
y.y.y.y
playbook.yml
---
- hosts: target
tasks: ...
Run:
ansible-playbook --ssh-common-args="-o ProxyCommand='ssh -W %h:%p root#x.x.x.x'" -i inventory playbook.yml
Setup:
My computer (linux / unix) has an arbitrary IP address
I can connect to a central linux server which has a static ip
Remote linux systems are set up so they only respond to central server IP address on port 22
I want to port forward through the central server so I can use MySQLWorkbench and make python scripting connections on port 3306 to the remote systems.
Ideally, I would like the syntax for ssh command to make the port forwarding work;
Suppose I want to forward local port 3307 to 3306 on the remote system. Assume my ip is x.x.x.x, the central server IP is y.y.y.y, and the remote system IP is z.z.z.z;
I think it has something to do with ssh -L but I can only forward to the central server so far. Maybe I need to connect to the central server, set up forwarding there, then set up forwarding on my machine? I think functionality exists to do it with a single command using ssh.
If this is a duplicate, it should not be marked as such because without knowing what magic keyword to search for, you can't find the duplicate;
Clarification: port 3306 is NOT open on the remote server. Only 22
ssh -L :3307:z.z.z.z:3306 user#y.y.y.y -Nf
Works fine
or
ssh -L 3307:z.z.z.z:3306 user#y.y.y.y -Nf
To only bind to x.x.x.x's localhost
The first example binds to all interfaces
edit...
Just seen that z.z.z.z only has port 22 open.
on y.y.y.y you will also need to have a local port open
run on y.y.y.y
ssh -L 3307:localhost:3306 user#z.z.z.z -Nf
then on x.x.x.x
ssh -L 3307:localhost:3307 user#y.y.y.y -Nf
run these commands in a screen for best results
You can actually condense these 2 commands together
ssh -L 3307:localhost:3307 user#y.y.y.y -f 'ssh -L 3307:localhost:3306 user#z.z.z.z -Nf'
ssh -L <local-port-to-listen>:<remote-host>:<remote-port>
The ‘L’ switch indicates that a local port forward is need to be created
Best method is to create the tunnel using putty (ssh client). so you can start the shell, and it will create the ssh tunnel for you. this is a good reference
https://howto.ccs.neu.edu/howto/windows/ssh-port-tunneling-with-putty/