I am trying to do the following. I have an internal ssh server at work (e.g. internal#192.168.1.13). This server is behind a gateway (external#gateway.work.com).
I would like to ssh to internal#internal-ssh.work.com from my home machine. To do so, I have been first doing ssh to log into the external gateway, and then from there I will log into the internal machine. the account names on the two systems are different.
I was wondering if this can be done in one step through some type of SSH tunneling. I have tried a few approaches that adapt what I see in different places, but keep getting error messages.
You can use
ssh -t external#gateway.work.com ssh internal#192.168.1.13
and you will need to either have public key crypto set up, or enter your external password, then your internal password.
Related
I've set up tailscale and connected to an exit node on my VPS on vultr.com. Predictably, I was kicked out and couldn't reconnect, as the VPS's public IP address has changed.
I can reboot the VPS and try again. What steps will I need to take? Does my VPS running behind an exit node even have a unique public address (which?), or does it need to be set up for something like port forwarding?
From looking at tailscale documentation, it looks like they came up with their own ssh, why? Why is the standard ssh inadequate for the purpose? I am not the admin of my tailscale network, and the admin is swamped right now. What can I do?
SSH uses TCP as transport and therefore requires the (srcaddr, srcport, dstaddr, dstport) tuple to be constant over the connection's lifetime.
I believe that since tailscale rotates connections dynamically, it is more suitable for use by clients than servers in a traditional client-server model, unless it provides an 'internal' virtual network over the distributed transport (which would kind of defeat the purpose of covering your tracks).
If you want to connect to your VPS over tailscale, you need to use their tools probably because of that. You can still connect directly to your VPS, though, through plain Internet, if it has any address of its own, and is not firewalled away (or similarly, NATed away). Your provider should either show you the address, or even better, provide access to out-of-band (like serial-port) command line access, where you can query the current addresses using commands like ip addr show.
In your Tailscale Admin console you should be able to see the machine's IP. Just use normal ssh and login that way.
So instead of ssh user#8.8.8.8 you'd do ssh user#100.64.0.1. Tailscale's own ssh client is useful if you want to hook deeper into their MagicDNS stuff, but it's not meant to be the only way to ssh into your machine.
If you run into errors, ping the machine you want to connect to (tailscale ping vps-machine-name). That should help you debug any tailscale client connection problems.
I have a microservice, let's call it RdsConnector, I want to test locally that is normally deployed on a machine on AWS. It connects to a MySQL instance, which is also in AWS, without any SSH tunnelling as they are in the same VPC. To connect to that MySQL instance from my local machine, I can use SSH tunnelling to get into the VPC I have set up in AWS. This is what that configuration looks like:
I could set up my microservice to also connect through SSH (optionally, perhaps), but I don't want to do that. Then I would have a different configuration running it locally vs in the cloud. What I want to do instead is set up some kind of proxy server on my local machine that will take the SSH credentials and do that SSH tunnelling, exposing the VPC MySQL endpoint locally. Then RdsConnector will just use that local endpoint, and I won't have to have a different config for RdsConnector just for local testing.
I'm not very familiar with the networking technologies in use here. I just know that there's no public IPs for my VPC, so I have to SSH in. I imagine that what I want is possible, but I have no idea what the moving parts would be.
Ok this turned out to be quite simple actually! The ssh program can do this for you, this is how I configure it with Mac OS ssh:
ssh -N -i "/Users/foo/aws_ssh_key.pem" \
-L "localhost:5990:stack-name-vpc-db.asdfqwerty.us-east-1.rds.amazonaws.com:3306" \
foo#12.34.567.890
With the -L flag, it'll proxy stuff over the SSH connection for you from the given endpoint to the provided endpoint on the other side. That -N flag is optional, it just turns off the regular SSH console since we only want to run a proxy server. The microservice can treat localhost:5990 as if it were the regular MySQL endpoint.
I have a machine that I want to setup an SFTP connection to. The SSH server is running properly, I can ssh into it from my client computer, and I can SFTP in from my smartphone. I'm just a bit confused on how to properly configure the ~/.netrc file. The server computer is running Ubuntu, the client computer is running OSX.
Here are my main requirements for what I'm trying to configure:
Alias. I don't have a DNS name for the computer I'm connecting to, just the IP address. ~/.ssh/config is great because it basically assigns aliases to connections, and then specifies the hostname, port, etc. Looking at the man page for ~/.netrc, I don't see a way to do this.
Private Key. This SFTP connection is validated using a private key. I don't see anything in the ~/.netrc man page about how to specify the key.
If ~/.netrc is the wrong way to go, what alternatives would be better?
I get this error message when trying to connect with ssh.
Disconnected: No supported authentication methods available (server sent: publickey,gssapi-keyex,gssapi-with-mic)
I create a instances(cent os), generated my webserver.pem, puttygen imported that and output a ppk
I have seen that it may be a permissions issue with the ~/.ssh on the server but how can i change the permissions on the server without ssh access to the server? Is there another way to connect that i am not aware of? I am quite new to the amazon ec2 stuff.
I am on a windows system right now using putty.
My security groups were incorrect. I remade the instance with the correct security groups
The below steps worked for me.
Edit sshd_config file sudo vi /etc/ssh/sshd_config.
Search for PasswordAuthentication
If it is no, change it to yes. For me it was commented. If so, uncomment it.
Restart sshd service sudo systemctl restart sshd.service
Done.
These are the basic steps generally when working with a public cloud, trying to create a Virtual Machine and connect to it.
Create a Virtual Cloud Network/ Virtual Private Cloud
Create an Internet Gateway and ensure the Route Table for the VCN has the entry to route internet bound traffic (destination 0.0.0.0/0) to the internet gateway
Create a Virtual Machine (Linux in this case), ensure it has a public IP ( VM be created in public subnet ), download the key pair (for example was in PEM format)
Create a Security Group and ensure ingress rule from source : 0.0.0.0/0, protocol: TCP, destination port: 22
Associate the VM with the Security Group at VNIC level at the time of creating the VM or post creation.
From Oracle Cloud documentation -
Just having an internet gateway alone does not expose the instances in
the VCN's subnets directly to the internet. The following requirements
must also be met:
The internet gateway must be enabled (by default, the internet gateway
is enabled upon creation). The subnet must be public. The subnet
must have a route rule that directs traffic to the internet gateway.
The subnet must have security list rules that allow the traffic (and
each instance's firewall must allow the traffic). The instance must >
have a public IP address.
Now connecting to VM using putty, basically you are doing a :
ssh user#ip_address —i private_key
a. Use puttygen and load the private PEM key that you downloaded. Once successfully imported, save the private key (optionally with a passphrase) as PPK in your local machine ( for example "your_pvt_key_name.ppk" )
b. Use putty to connect to the VM's public IP. Ensure in putty when connecting to the VM that private key is provided for authentication. In the section Connection->SSH->Auth, browse for the "your_pvt_key_name.ppk" and then go back to the Session and "Open" the VM. If the VM is on public subnet with correct route table entry, you should see the login screen. In case the VM is not available on internet, it wont connect !
c. Once you see the login screen most important and which is the probable cause of the above error, login with correct user name, such as "ec2-user" in AWS or "opc" in OCI. Using an incorrect user name results in this error.
No supported authentication methods available (server sent: publickey,gssapi-keyex,gssapi-with-mic)
I purchased shared hosting from Vexxhost.I wanted to host my Rails application with them.I was given cpanel details.I generated SSH keys using the cPanel and converted it to .ppk format.Next, i downloaded the key.But when i try SSH login using Putty, i get the message Server Refused Our Key.Then i'm prompted for the password.When i enter password, message is displayed: Shell access is not available for your account.Contact support.I did contact support, but no reply.Am I doing any mistake in the procedure?
I haven't used cpanel to generate ssh keys, usually I do it at the ubuntu console. Is it possible that the ppk conversion has encoding issues? or it not done right?
Do you have access to a linux box? It would be simpler to test it there.
I have configured a server myself with ssh access, and if user does not have ssh access they are presented with user/pass. So it appears that your ssh credentials are denied, but your password is recognized as accurate. Authentication is happening.
About the issue of shell support. It could be that they enable shell support only if you connect with valid ssh credentials - in which case, you need to contact support.
Or, your account does not have ssh access, and you still need to contact support.
hope it helps