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Java SSH Client (running commands and catching answers) Remote Device

I want to implement application working on Internet (I have remote Devices connected using Internet), I want to develop Java application to perform changes on remote devices....
I found this link example/code (http://twit88.com/blog/2007/12/22/java-writing-an-automated-telnet-client/) working in Telnet but is insecure I want to use SSH.
JSCH can help me (http://www.jcraft.com/jsch/)? or have you another alternative.
If you have similar code....
Thank you

JSch is be the best solution.
You can use my code snippet as an example:
https://gist.github.com/kobylinsky/1c2b21c73b68a0daa91f

How to debug a jar remotely from netbeans

I'm trying to figure out how to debug my jar that is running remotely. Here is my scenario:
My .jar will be running from a VPS. This jar basically runs a server
for a game, so it also connects to a mysql db. I start the server with 3 .bat files that looks something like this:
set CLASSPATH=.;dist\aries.jar;dist\mina-core.jar;dist\slf4j-api.jar;dist\slf4j-jdk14.jar;dist\mysql-connector-java-bin.jar
java -Xmx500m -Dwzpath=wz\ -Djavax.net.ssl.keyStore=filename.keystore -Djavax.net.ssl.keyStorePassword=passwd -Djavax.net.ssl.trustStore=filename.keystore -Djavax.net.ssl.trustStorePassword=passwd net.world.WorldServer
pause
What I want to do is start the server on the vps like normal, but debugging the server on my local machine via Netbeans IDE. I don't know if this is possible because people will be connecting to the server (although, I will be debugging a test server which will only have me online).
Note: I have done a lot of searching before coming here and a lot of what I found had to do with using xdebug & php which has doesn't have much to do with my situation (I don't think)
-Thanks

There's a NetBeans FAQ page about this.
In brief:
Add the remote debugging options to your Java command. For example:
-Xdebug -Xrunjdwp:transport=dt_socket,server=y,address=8888,suspend=n
Then, use the attach debugger option in NetBeans and select your server and the port you used above (8888). It's pretty much that easy.
You may want to think about network and firewall considerations, as you may have noticed there are no passwords involved, so anyone who can connect to the port can debug your app. This could be a big security risk. Your VPS provider probably has some tools to help with setting up a secure, private connection.

javax.mail.MessagingException: Could not connect to SMTP host locally via netbeans

I know that there are many questions on this topic, and I have been searching for an answer for the past 4 months. Everyone says check host address, port, and firewall. Well I have done these items, but am still not having any success.
We are running our web application locally using Apache Tomcat 7.0.27 through Netbeans 7.2.1 and are no longer able to connect to the SMTP server to send emails. When running the application on a virtual machine located on the server, there is no issue connecting. We have no problem connecting and sending mail using telnet locally with the same parameters.
We have tried looking at the SMTP logs on the server, and were able to access some logs, but can't find any related to the refused connection. Which SMTP logs would provide more information on this issue? I tend to think that since the connection is refused it may not even trigger any logging, is this a correct assumption? We migrated to IIS7 several months ago and were having trouble accessing IIS 6.0 Manager, so I am not sure that they are even set up correctly.
Does anyone have any ideas of how to further troubleshoot the connection?
Thank you in advance, and please let me know if I can provide any further information.

Almost certainly this is a problem with a firewall or anti-virus program on your local machine. If you can connect from that machine using telnet but can't connect from that same machine using a Java application, there's something on that machine preventing Java applications from connecting.

I recently faced the same problem while running the Mail sending code and what I found is that the code which I had written recently is using the Java version Jre7. But the older codes run in Jre 6 environment, which works perfectly even now also.
So what I had done is I just change the Jre version of my recent code to Jre 6. After that the code works perfectly without any exception.
So try to change your runtime environment to lower Jre and run the code.

Hosting an H2 database and accepting connections

I've looked all over for this for quite a while so I'm just going to ask it here;
How do I set up an H2 db in server mode so I can connect to it via the internet from a different machine? How do I start the engine in server mode and leave it running on a machine to accept connections? I can forward the ports and everything fine, it's just getting the engine in "receiving" mode that I'm dumb about.
I'm sorry, I've really looked everywhere. I want to be able to connect to the db and add data from a mobile app. All of the app and transmission data is working great, I just need to be able to run a server with the db on it and receive the data. Any tutorial or documentation that is clearer than the stock H2 server mode documentation would be really appreciated.
Thanks!

For security reasons, by default the H2 servers (including the TCP server) are protected against remote access. The error message you get on the client should be clear this. You have to explicitly enable remote access using -tcpAllowOthers (for the TCP server):
java -cp h2.jar org.h2.tools.Server -tcp -tcpAllowOthers
This will only start the TCP server - see the documentation for details.

$ java -cp h2.jar -Dh2.binAddress=0.0.0.0 org.h2.tools.Server
See http://h2database.com/html/advanced.html#server_bind_address

How can I determine if another local machine is alive?

Is it possible to make my local computer function as a gateway in Java? I need the other local machines to connect directly to my computer to see if they are alive or not.

You could run a Java server program on your desired PC and let it listen on a port. Then you could use other programs (browser, other Java programs etc.) to connect to this port, and send commands to be executed by the Java server program.
If you just want to see if the PC is turned on or not, I'd just use the ping command though. Or see this answer: How to do a true Java ping from Windows?

Surely it's the other way round? Surely you want to connect to the other machines to see if they're alive? In which case see InetAddress.isReachable().

Try this.
Create a Java Server Socket, which keeps listening to the client at some port.
Write a client in Java which connects to the Server, wrap the connection logic in try-catch block....
If your host is alive the try code is executed which contains the code to connect to the
Server, if this connection process fails you will get UnknownHostException, here you can instead type a message that the connection failed.

You could more easily manage and control this by polling for other devices from a central server. If possible, avoid unnecessary client/agent apps that might tax your development and support resources as well as taking up RAM on the client workstations.
There are many monitoring tools that already do what you want. I'd have a look at Nagios, for example.
If you want to develop your own app, do your own quick troubleshooting, or just get a feel for network discovery tools, then take a look at NMAP. You could, for example, search a subnet for anything that responds to TCP:445 and see what Windows machines are alive.

If you do go the Nmap route, please have a look at Nmap4j on Sourceforge. It's a Java wrapper API that simplifies the work needed to integrate Java and Nmap.
Cheers!