SSH tunnel not working - empty server response

Question

I am trying to setup an SSH tunnel but I am new to this process. This is my setup:

Machine B has a web service with restricted access. Machine A has been granted access to Machine B's service, based on a firewall IP whitelist.

I can connect to Machine A using an ssh connection. After that I try to access the webservice on Machine B from my localhost, but I cannot.

The webservice endpoint looks like this: service.test.organization.com:443/org/v1/sendData

So far, I have created an ssh tunnel like this: ssh -L 1234:service.test.organization.com:443 [email protected]

My understanding was that using this approach, I could hit localhost:1234 and it would be forwarded to service.test.organization.com:443, through Machine B.

I have confirmed that from Machine B, I can execute a curl command to send a message to the webservice, and i get a response (so that is working). I have tried using PostMan in my browser, and curl in terminal from localhost, but I have been unsuccessful. (curl -X POST -d @test.xml localhost:1234/org/v1/sendData)

Error message: curl: (52) Empty reply from server

There's a lot of material on SSH and I am sifting through it, but if anyone has any pointers, I would really appreciate it!

have you checked that port forwarding is enabled in sshd_config? by default it isnt usually — camelccc
– camelccc, Commented Jul 2, 2015 at 19:06
I found that the request is making it to the destination but no response is coming back because the request originated from Localhost, which violates the firewall whitelist rule. How can I make it so the HTTP request header says its from Machine B? — user1521567
– user1521567, Commented Jul 6, 2015 at 13:57

DenisS · Accepted Answer · 2016-03-30 17:22:06Z

4

Try to add Host HTTP header: curl -H "Host: service.test.organization.com" -X POST -d @test.xml http://localhost:1234/org/v1/sendData

edited Mar 30, 2016 at 17:22

answered Mar 30, 2016 at 17:15

DenisS

414 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

user1521567 · Accepted Answer · 2015-07-15 14:41:34Z

1

The networking issue was caused by the request format. My request object was built with a destination of 'localhost:1234'. So even though it was reaching the proper machine, the machine ignored it.

To solve this I added a record in my host file, like this: service.test.organization.com 127.0.0.1

Then I was able send the message. First I opened the tunnel, ssh -L 443:service.test.organization.com:443 [email protected], Then using using this curl command: curl -X POST -d @test.xml service.test.organization.com:443/org/v1/sendData

The host file causes the address to resolve to localhost, then the ssh tunnel knows to forward it on.

answered Jul 15, 2015 at 14:41

user1521567

1,8433 gold badges22 silver badges31 bronze badges

Collectives™ on Stack Overflow

SSH tunnel not working - empty server response

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related