I currently have to SSH 3 times to get into the machine I need:
ssh gatekeeper
[passwd1]
ssh master_server
[passwd2]
ssh my_machine
[passwd3]
Is there a better way to do get into my_machine? Pretty cumbersome to have to do it every time.
Nice - this worked:
Host my_machine
Hostname my_machine
ProxyCommand ssh user2#master_server -W %h:%p
ProxyCommand ssh user1#gatekeeper -W %h:%p
I don't really know for 3 SSH, but here is my way for 2 (lets say : me -> master_server -> my_machine).
You need to add a configuration file in your home :
~/.ssh/config
Then you write in that file :
Host my_machine
Hostname my_machine.example.com
ProxyCommand ssh other_or_same_login#master_server -W %h:%p
And you call
ssh login#my_machine
Then you will have to enter twice your password (or 3 times in your case). If you don't want to type passwords, you can use the key access option.
For another ssh, I guess you need to write another section in the config file, but since I can't try I don't wan't to say something wrong.
Hope this helps.
Related
Here is my situation. I want to access a server through a jumpbox/bastion host.
so, I will login as normal user in jumpbox and then change user to root after that login to remote server using root. I dont have direct access to root in jumpbox.
$ ssh user#jumpbox
$ user#jumpbox:~# su - root
Enter Password:
$ root#jumpbox:~/ ssh root#remoteserver
Enter Password:
$ root#remoteserver:~/
Above is the manual workflow. I want to achieve this in ansible.
I have seen something like this.
ansible_ssh_common_args: '-o ProxyCommand="ssh -W %h:%p -q user#jumpbox"'
This doesnot work when we need to switch to root and login to remote server.
There are a few things to unpack here:
General Design / Issue:
This isn't an Ansible issue, it's an ssh issue/proxy misconfiguration.
A bastion host/ssh proxy isn't meant to be logged into and have commands ran directly on it interactively (like su - root, enter password, then ssh...). That's not really a bastion, that's just a server you're logging into and running commands on. It's not an actual ssh proxy/bastion/jump role. At that point you might as well just run Ansible on the host.
That's why things like ProxyJump and ProxyCommand aren't working. They are designed to work with ssh proxies that are configured as ssh proxies (bastions).
Running Ansible Tasks as Root:
Ansible can run with sudo during task execution (it's called "become" in Ansible lingo), so you should never need to SSH as the literal root user with Ansible (shouldn't ssh as root ever really).
Answering the question:
There are a lot of workarounds for this, but the straightforward answer here is to configure the jump host as a proper bastion and your issue will go away. An example...
As the bastion "user", create an ssh key pair, or use an existing one.
On the bastion, edit the users ~/.ssh/config file to access the target server with the private key and desired user.
EXAMPLE user#bastion's ~/.ssh/config (I cringe seeing root here)...
Host remote-server
User root
IdentityFile ~/.ssh/my-private-key
Add the public key created in step 1 to the target servers ~/.ssh/authorized_keys file for the user you're logging in as.
After that type of config, your jump host is working as a regular ssh proxy. You can then use ProxyCommand or ProxyJump as you had tried to originally without issue.
I'm just trying to use PuTTY to get an SSH connection to my servers.
These servers allow incoming SSH connection only from another specific server ("MySshProxyingServer" in example below).
Using Linux this is no problem with the ssh -W command.
In PuTTY I can't find the options to create such a connection.
Example under Linux (~/.ssh/config):
Host MyHostToConnectTo
Hostname xx.xx.xx.xx
User root
Identityfile ~/.ssh/id_rsa
ProxyCommand ssh MySshProxyServer -W %h:%p
Anyone knows how to use such a config in PuTTY?
If you want to "jump a host", then using "local proxy command" is an overkill. Recent versions of PuTTY have this build-in. Go to Connection > Proxy, and in "Proxy type", select "SSH to proxy and use port forwarding". Then specify the details of the intermediate server below (like Hostname, Port, Username, Password [or load your private key to Pageant]).
(It's actually an overkill for OpenSSH too, as it has more user friendly options for this purpose too, see Does OpenSSH support multihop login?)
To answer your literal question: The equivalent in PuTTY is "local proxy command". You can use the plink.exe with the -nc switch instead of the ssh with the -W switch:
The "local proxy command" is:
plink.exe %user#%proxyhost -P %proxyport -nc %host:%port
An alternative is to open a tunnel via the "MySshProxyServer" first using another instance of PuTTY (or Plink).
See for example:
How to create SSH tunnel using PuTTY in Windows?
My guide for tunneling SFTP/SCP session. It's for WinSCP, but just use PuTTY instead of WinSCP in section Connecting through the tunnel.
Just in case you still use password for your jumphost is the option for that with an example.
plink.exe %user#%proxyhost -pw %pass -P %proxyport -nc %host:%port
When you want to start putty.exe from commandline it works this way:
putty.exe -proxycmd "plink.exe user#jumphost -P 22 -nc targethost:targetport" user#foo
According to the docs it uses stdin/stout of the proxycmd so "foo" is ok as target hostname here.
Suppose we want ssh to 172.16.0.21 via 8.8.8.8
login name in both hosts is john
path to private key is C:\users\john\.ssh\private.ppk
.
plink.exe -v -ssh %user#%proxyhost -P %proxyport -nc %host:%port -i "c:\Users\john\.ssh\private.ppk"
p.s.
If your private key has password protect then you must additionaly launch pageant and load your private key there
p.s.
if you want to use command line only then:
putty.exe -proxycmd "plink.exe john#8.8.8.8 -P 22 -nc 172.16.0.21:22 -i c:\Users\john\.ssh\private.ppk " john#172.16.0.21 -i c:\Users\john\.ssh\private.ppk
I am away from home, and need to proxy jump via my home server to connect to a number of sites.
The settings in .ssh/config work 100% of the time every time when executing from the command line, but coda simply refuses to use these connections.
Host home
Hostname my.home.server
Port 222
ProxyCommand bash -c '/usr/local/bin/knock -v %h $KNOCKS; sleep 1; exec /usr/bin/nc %h %p'
Host host1
Hostname host1.com
User root
Host home-host1
Hostname host1.com
User root
Host home-*
ProxyCommand ssh -W %h:%p home
So If I want to connect via home I:
ssh home-host1 and it jumps through my home to host1
Now this works all the time, every time for ssh via the console, but coda simply wont connect.
In the coda setup I have added home-host1 as the server and tried setting and clearing the user name and port so that just like ssh in a terminal everything comes from the config file.
I have also cleared known_hosts just in case it was caching something from there but no-go.
What am I doing wrong ??
Wow, after a lot more trial and error I succeeded.
coda does not appear to like ProxyJump but it will work with ProxyCommand
Host home-*
ProxyCommand ssh -W %h:%p home
with two consecutive ssh authentications I mean the following:
I ssh to remote system A
from remote system A, I ssh to remote system B
There is no way to ssh to B directly.
I have no problems mounting directories from A using sshfs.
I thought about mounting directories from B on A but unfortunately A does not have sshfs installed. Even if, I would not know if it works.
Is there maybe another way to access directories on B in a convenient way?
My ~/.ssh/config looks like this now:
Host A
User user
HostName A.example.com
ControlMaster auto
ControlPath ~/.ssh/%r#%h:%p
Host B
User user
HostName B.example.com
ProxyCommand ssh -W %h:%p A
How would my sshfs command look like?
This does not work:
sshfs -o allow_other,defer_permissions -o user#B.example.com:/somedir ~/somedir
It outputs the error message:
remote host has disconnected
Use ProxyCommand or ProxyJump to do that transparently for the end application (sshfs). For example in ~/.ssh/config
Host A
# other configuration options needed
Host B
ProxyCommand ssh -W %h:%p A
Then you should be able to use sshfs transparently by directly specifying host B.
I would like to use a ssh_config file instead of the traditional ~/.ssh/config. I have a simple configuration for accessing hosts through a bastion host (on port 23 for example).
ssh_config :
host bastion
hostname bastion.mydomain.com
port 23
host *.server
proxycommand ssh -W %h:%p bastion
ssh -F ssh_config test.server is not working and throw me "ssh: Could not resolve hostname bastion: Name or service not known".
But, if put this config in ~/.ssh/config, then ssh test.server works.
As I understand it, the proxycommand is unable to use the config file given in the command line.
If I want my command line config file to work, I need to put
proxycommand ssh -W %h:%p bastion.mydomain.com -p 23
but this seems to violate a simple DRY principle (the port and the domain are repeated). The config file I'm willing to build is much much longer and complex.
Is there a good way to achieve what I want, i.e. a simple, non-repeating, config file usable in command line for which proxycommand works ?
Half of an answer:
Rather than using the config file recursively, try not relying on the config at all for the proxy command.
host *.server
proxycommand ssh -W %h:%p bastion.mydomain.com -p 23
This allows it to be portable, but doesn't solve your other issue of having to do this on every line, and makes changing the bastion host address a difficult process.
you need to pass proxycommand ssh -W %h:%p bastion -F [your custom ssh config]