I'm running a web service on serverA:8890, this includes the regular HTTP service and websocket services. I'm trying to set up the SSH port forwarding from serverB to serverA, so I can access the ServerA's service through SSH tunnel.
Here is my command:
ssh -f user#serverA -i user.pem -L 2000:serverB:8890 -N
When I connect to ServerB:2000, I can see all the regular web services, but the websocket part is not working.
Any idea how to solve this?
Thanks
I believe your tunnel needs to be:
ssh -f user#serverA -i user.pem -L 2000:serverA:8890 -N
Related
I have the problem that at work I can not connect via network to expo, so I need to use tunnel, which is fine. However sometimes the tunnel is really slow destroying any developer expierience.
Since I can also host expo locally on localhost I had the idea of simply ssh-tunneling to a remote server that has an open port.
my remote host runs ubuntu
so i SSH there like so:
ssh -R 0.0.0.0:19000:0.0.0.0:19000 user#ip
in order for this to work i also added
GatewayPorts clientspecified
to my /etc/ssh/sshd_config
...
sudo netstat -plutn
shows me
tcp 0 0 0.0.0.0:19000 0.0.0.0:* LISTEN 20183/2
so accepting requests (i also tried to forward port 19001 to get something back when i enter it in the browser which worke fine)
However when i enter:
exp://serverip:19000 into the expo client on my android phone he can't connect.
Any ideas on help?
It looks like Expo uses multiple ports 19000, 19001, and 19002. So you will need to forward all of these.
e.g.
$ ssh -f -N -R 19000:localhost:19000 user#ip
$ ssh -f -N -R 19001:localhost:19001 user#ip
$ ssh -f -N -R 19002:localhost:19002 user#ip
Also, you can set the REACT_NATIVE_PACKAGER_HOSTNAME environment variable to use the remote host.
$ export REACT_NATIVE_PACKAGER_HOSTNAME="ip"
$ expo start
Establishing SSH tunnel can done from the command line by explicitly giving
ssh -N -f -L 18888:192.168.224.143:8888 username#192.168.224.143
or defining tunnel in ~/.ssh/config file
Host tunnel
HostName 192.168.224.143
IdentityFile ~/.ssh/mine.key
LocalForward 18888 192.168.224.143:8888
User username
and then running,
ssh -f -N tunnel
Is there a way to start this tunnel without running the ssh ssh -f -N tunnel command explicitly?
I would like to establish this tunnel whenever my machine boots up. Do not want to add it in init script. Can it be done with SSH configuration itself?
No. SSH configuration is not designed to start something for you automatically. You need to add it to your startup applications or init script/systemd service, if you want to start it automatically after the network.
I also recommend you to use autossh which will take care of re-establishing the tunnel, if it fails for some reason.
I have a Spark installation running under YARN on a remote cluster, with a firewall between me and the head node. I can use a ssh tunnel to access the head node:
> ssh -N -f -L 10000:remotenode:10000 between_machine
and this setup works, for example, to access a HiveServer2 running on remotenote. If Spark was running in cluster mode, I would need to just do the same for the 7077 port and direct the pyspark client to localhost with
> ssh -N -f -L 7077:remotenode:7077 between_machine
> ./pyspark --master spark://localhost:7077
How can I do that with Spark running under the YARN scheduler?
If you are looking for a port to connect, here is a quote from the doc:
You can access this interface by simply opening
http://:4040 in a web browser. If multiple SparkContexts
are running on the same host, they will bind to successive ports
beginning with 4040 (4041, 4042, etc).
If you are just looking for a more universal way to get to the host via ssh "tunnel", you could try ssh working as socks proxy:
ssh user#host -D 20000
And then configuring your browser to connect via socks proxy (host - localhost, port - 20000).
I have dispynode running on a remote server. I'm trying to open an SSH tunnel from my computer (client) and configure dispyJobCluster to use this tunnel. But it's not working. Am I not configuring this right ? Here's how I'm doing this :
( p.s . i don't have a deep knowledge in distributed & parallel computing nor networking, I'm a civil engineer so please excuse me if I don't use the right technical words sometimes)
SSH tunnel​ :
plink -v -ssh -L 61:localhost:21 user#myserver.net
This will forward connections to port 61 to localhost:21 on the server where dispynode is running
dispynode :
sudo dispynode.py -d --ext_ip_addr localhost -p 21 -i localhost
will listen on port 21 and transmit using localhost which leads it though the tunnel back to the client
with this dispyClient JobCluster code :
cluster = dispy.JobCluster( runCasterDispyWorker,
nodes=[('localhost',61)], \
ip_addr='localhost', \
ext_ip_addr='localhost', \
port = 61, \
node_port = 21, \
recover_file='recover.rec', \
)
When I launch the dispy.py I get the following error in the command prompt from which I opened the SSH tunnel :
Opening connection to localhost:21 for forwarding from 127.0.0.1:64027
Forwarded port closed
At least I guess this means that dipsy is trying to access the opened SSH tunnel but I'm not sure what's happening server side. It seems that dispynode receives nothing.
Running a quick traffic capture with TCPdump on the server confirms it. For some unknown reason, the port changes to 64027.
I have also tried to open 2 SSH tunnels simultaneously :
One for client-to-server communications
plink -v -ssh -L 61:localhost:21 user#myserver.net
One for server-to-client communications
plink -v -ssh -R 20:localhost:60 user#myserver.net
but with no luck. I'm not even sure whether it is best to use remote forwarding or local forwarding
I tried this solution that the developer of dispy himself suggested but it didn't work for me :
http://sourceforge.net/p/dispy/discussion/1771151/thread/bcad6eaa/
Is the configuration i used above wrong ? Should I use remote or local forwarding ? Why does the port change automatically, can it be because of my company's firewall blocking the connection through the ports i'm trying to use ? Has anyone managed to run dispy through an SSH tunnel before ?
This worked for me. It should work for you :
SSH tunnel ( i'm using PuTTY's plink.exe to create the tunnel ):
plink -v -ssh -R 51347:localhost:51347 [username on server]#[server's Public IP or DomainName] -pw [USER PASSWORD on server] -N
dispynode (running on the server - linux):
sudo dispynode.py -d --ext_ip_addr [public IP or domain name of server]
JobCluster (dipsyClient):
def Worker():
os.system('echo hello') #prints hello on the server running dispynode
return 0
import os
import dispy, logging
cluster = dispy.JobCluster( \
Worker, \
nodes=['IP public or domain name of server'], \
ext_ip_addr='localhost', \
recover_file='recoverdispy.rec', \
)
job = cluster.submit()
print "waiting for job completion"
job()
print('status: %s\nstdout: %s\nstderr: %s\nexception: %s' % (job.status, job.stdout, job.stderr, job.exception))
Try this piece of code .. Make sure the required ports are allowed to be used
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