SSH connection fails when using local library internet - ssh

I normally use a private ip address (with a custom port number) to SSH connect to my server for a remote development. Although I mostly use a private ip address, the port is forwarded properly and I am able to SSH in to the server with the public ip address.
(tested with mobile network hotspot)
Now I am in the local library using the their internet (with my laptop), the connection gets refused and even fails the simple ping test.
Would this be because the library's network is blocking such connection for the security purposes? If so, is there anything that I could do? Or should I just use a mobile hotspot?

Related

How to connect db from local machine that can only be connected from windows remote desktop

The question says it all. But to elaborate.
I have a oracle db running at some remote host. ip: 10.0.0.121 port: 1521
It can be accessed when I connect to a windows remote desktop machine.
Now how can I connect to this remote db from my local machine?
I believe that localtunnel is similar to telebit in that you get an encrypted https connection, not a plain tcp connection (which is good).
If I understand correctly, you'll want to use localtunnel (or telebit or perhaps even ngrok) on the windows machine to expose its database connection to the outside world. You'll want to use https (and absolutely not tcp or http which would leak database passwords and all your data) to create the tunnel.
Then you'll need to run something like sclient (or stunnel) on the computer that's doing the connecting to "unwrap" the https connection back to plain tcp. It might look like this:
sclient example.localtunnel.me:443 localhost:1521
In your database client or application you would then use localhost:1521 in your database connection string (not the https address).
This gives you the security of an encrypted connection and the convenience of exposing ports out to the world, all without adding any complexity to your application or client - you just run it as normal, connecting to localhost.
Comment if you need any additional clarification.

RDP through ICMP

I have got a VM in Google Compute Engine. And I want to use this VM using RDP. I have enabled the firewall settings to accept RDP(TCP:3389). This works fine when I connect to it using a LAN connection. But when I try to connect to this VM using an ICMP connection(ICMP tunneling software), it shows an error that couldn't connect to the remote computer for one of these reasons:
1. Remote access to server is not enabled.
2. The remote computer is turned on.
3. The remote computer is not available on the network.
But my current configuration works fine when I connect over a LAN. I want to use RDP using an ICMP tunnel. Is there a way to use RDP using ICMP?
Ping also works when trying to connect through ICMP.

Connecting to ubuntu home server without internet connection

I am running an Ubuntu server with my laptop through an Orcale VirtualBox and I try to maximize the bandwidth of my home server, as it really slows down my internet connection. My router supports up to 300Mbit upload/download speed and my laptop wifi's card up to 150bit.
I configured my server with the following(static IP, configured by vim /etc/network/interfaces):
auto eth0
iface eth0 inet static
address 192.168.1.240
netmask 255.255.255.0
gateway 192.168.1.1
dns-nameservers 192.168.1.1
192.168.1.1 is my default gateway, and I just configured a static IP which ends with 240.
When my laptop's WIFI is on, I can easily access the server's files(.html files etc) through chrome from any computer on my house, as I just need to enter the server's IP into the browser, plus I can access the server through SSH. But when It's off, I can't even access the server's HTML files through the laptop itself, though I can see that the server is still running on VirtualBox. When I turn the WIFI once again, I can run services which require Apache2 but they really slow my internet connection, as a result I can barely surf the web. I am trying to configure the server to use only the bandwidth of my router, since my actual internet connection is 30 Mbit download and 1.90 Mbit upload(according to speedtest), and It probably interferes with it. Is it possible to access the server without WIFI connection, so it will purely use my router's speed?
Any help would be appreciated.
1) Looks like you using bridged networking in VM config. When your network adapter is connected to real network - you can interact with your VM via network bridge. When it's not connected - your bridge is also closed. If you need to interact with your VM without WiFi connection - you can add one more virtual network adapter to you VM config: use "Host-only" adapter and configure it on both VM and host PC. Your VM will use new host-only adapter to interact with your PC, and old bridged adapter to interact with other network.
2) Check your WiFi speed near the router. Maybe it's too far or provides too weak signal.
PS. Sorry for my poor english.

Connecting to a remote machine through client-server

I have created a simple tcp client-server application in vb.net. Everything works fine when i set local host (127.0.0.1) as the ip address. I wish to make a connection to a remote machine (keeping client at my machine and server on the other - or vice versa).
EDIT:
ok, the code of interest is as follows:
the server:
Dim server As TcpListener = New TcpListener(IPAddress.Any, port)
the client:
Dim theip As IPAddress = IPAddress.Parse(TextBox1.Text)
client = New TcpClient(theip.ToString, port)
Now, what should i enter in "TextBox1.Text" if i have my client on a remote machine (connected over internet) and server at a different computer (whose external IP address is known)?
Can i enter the external IP address of the machine running the server directly in the text box? Also, do i need to take care of things like "port forwarding" / "let firewall allow the connection" and all? If yes, can you please guide me or link a tutorial so that my application does this automatically or is there an alternative approach to achieve this and so that port forward is not required? Thanks a lot!
You say the other machine has an external ip address. This implies it also has a local ip address; ie it is behind a NAT firewall or similar. In this case, you will have to configure the firewall to allow communication to take place, eg by setting up port forwarding.
Applications such as MSN Messenger, VOIP clients etc have elaborate mechanisms to negotiate this automatically, but they're often not very successful.

Connect to remote Openbravo ERP Appliance

I have my Openbravo appliance running by VMWare workstation on top of Win7 which is in a LAN connected to internet by router.
When I start the appliance. I can access ERP web console by typing in the address it gave at the end of the process (for example, 192.168.1.107). All computer in the LAN can access this address as well which is fine for now.
However, in the future, I need to access this console from my home pc running Win7 (which is, of course, connected to the internet). How do i set this up?. I have try the method given in http://planet.openbravo.com/?p=8612 (see case 3 - Expose my local ERP into a remote network)
I tried (in Openbravo Appliance console running in VMWare)
ssh -R :9999:localhost:80 myhomepc#101.108.70.128
(where 101.108.70.128 is the ip of my home pc read from whatismyip.org)
but it give the following error:
ssh: connect to host 101.108.78.128 port 22: connection timed out
Do I missed any step required?
What should i do the successfully connect to my Openbravo instance?
Best is to ask those questions directly in the Openbravo ERP forums over there: http://forge.openbravo.com
The case 3 from the blog-post you are referring to makes 2 implicit assumptions.
a.) the remote computer runs an ssh-server
b.) This ssh-server can be connected to from the erp instance
One of the two assumptions seems to not hold in your case either your win7 box does not run an ssh server and/or the router of your home network does not forward port 22 from the outside to your win7 box.
Without further information i assume both items are not done.
Let me propose another solution instead. As you want to connct to the commandline of the erp appliance from home you could do the following:
Configure the router of the network with the erp appliance to connect some external port (i.e. 2222) to the ip of the appliance, destination port 22.
This will allow you to access it from the home network (or any other system from the internet knowing the ip/port).
Using an external port different from 22 some simple ssh brute-force passwords scans.
As the appliance by default does not allow login by password but only allows authentication by public-key this is secure to not allow unauthorized access to your system.
After this either use case 1 from the blog-post or an normal ssh tunnel like (ssh -p external-port user#externalipoferplan -L 9999:localhost:22' and then access the ERP via 'http://localhost' from your win7 box.
If that is too complicated and you want to just make the ERP webinterface available from the internet without having the extra ssh security in the middle then you can just configure the router of the erp lan instead to forward port 80 or 443 (http or https) to the erp-instance and access the system directly from anymore as if it would be on some public server in the internet.