Help
Getting Started
Reverse HTTP Starter is easy to use. However, before you start, there are some things to know that would make it even easier.
This is the interface to the program.
Main Interface
A URL where you are able to upload and delete ‘markers’ (e.g. text or html files) is required for the program to work. Enter your URL in top field. This must be a direct link to the text or html file that will be checked for keywords (e.g. http://www.myoffice.com/joe/rhs/marker.txt)
Next, you need to enter at least one keyword to look for at that URL (within the marker itself) that will trigger your batch or EXE file. Think of something unique and mnemonic.
Select the batch or EXE file that will execute on your machine (the one running RHS) upon finding that keyword. The first keyword corresponds to the first batch file, the second keyword to the second batch file and so forth.
The path for the batch or EXE file(s) can be anywhere on your computer but make sure that the path does not contain an ampersand (‘&’). This is because the ampersand is normally used for concatenation in programming code. Your files should also not reside on a network drive. Keep them local.
You may enter up to three different keywords and three different batch (*.bat) and/or EXE files to execute with them.
Press the ‘Test’ button once to see if everything is in order. This will test to see if the URL, keyword(s) and batch/EXE file(s) are working.
Enter an interval (in whole seconds, not fractions) between checks. This is how long RHS will wait between checking with your URL. Deciding on this interval depends on a lot of factors that only you will know. You need to give enough time for whatever it is you are executing to start and perhaps even complete whilst at the same time, not making you wait too long for it to happen. Also, you don’t want the same batch or EXE file executed twice before you have had time to remove the marker from your Web server. For most purposes, 120 to 180 seconds is nice. An example of this is given later.
Once you are sure of the details, use ‘Open File’ to call upon the rhs.txt file in your program folder. Here, you can copy and paste those details in their corresponding lines so that the next time RHS is run, you don’t have to enter them manually again. Just press, ‘Read File’. A quick guide on using this file is given in the help menu. Press the ‘Reset’ button to erase all fields quickly.
Now, you’re all set. Press the ‘Start’ button and RHS begins its sentinel work until you stop or exit the program. The ‘Status’ frame shows you if any of your keywords were found in the marker and also how many checks to your URL there have been. In the ‘Interval’ frame, you can enable a countdown which will show you how many seconds remain until the next check of your URL or disable it, if you prefer.
RHS minimizes to the system tray by default and operates in the background so you don’t have to worry about it. Even better, it supports automation. If you look under the ‘Options’ menu, you will find ‘Auto Start’ and ‘Run On Windows Start’. ‘Auto Start’ means that when you start the program, your rhs.txt file is automatically read and checking begins with the program minimized. ‘Run on Windows Start’ means that a shortcut to the program is placed in your Startup folder so the program starts when Windows starts. Disabling this option deletes the shortcut. Usually, both ‘Auto Start’ and ‘Run on Windows Start’ are enabled.
Once set, your configuration settings are preserved automatically.
The evaluation version is limited to 75 checks of the URL per session. The registered version has no limitations at all and entitles you to all future upgrades of the program, free of charge.
Some Background
RHS has many uses. The concept is based on remote administration. There are many tools which do this but it is often a complicated process. RHS facilitates remote administration for any number of tasks, depending on your needs. Because it accesses the Web, there are also usually no problems even if you are behind a proxy server and strict corporate firewall at your workplace. Upon identifying the appropriate keywords in your marker, the program will execute tasks on your computer as if you were there yourself. This however, depends on the efficacy of your batch and EXE files.
The Windows operating system supports batch files which are scripts that can be tailored to do a variety of tasks such as starting programs (even with command line parameters), accessing a Web server through the FTP protocol, backup data, deleting and moving files, setting timers etc. There are many websites which teach you how to write batch scripts. They are easy to learn and once you’ve gotten used to it, you’ll wonder how you ever worked without them.
In fact, it is with a batch script that you will even make uploading and deleting markers from your Web server as easy as the click of a button. Imagine you are sitting at home and suddenly require something to be executed on your work computer. Let’s say it is the task of e-mailing a particular file on your work computer’s hard drive to your Web e-mail address, so you can download it. There isn’t really an easy way to access the file because it is on your work PC’s hard drive, behind a proxy server, firewall and is part of your organization’s secure LAN (local area network). You would actually have to be at work to access the file. Work might be 5 miles or 5,000 miles away; it doesn’t matter. However, you had planned for such a situation and prepared the batch scripts necessary to automate this process. Great. The only problem is, how do you start the batch script from home? You would simply FTP your marker and wait for the batch script on your work computer to be executed by RHS. Once you receive the file via e-mail, you then delete the marker so it doesn’t send the file again.
This is just one possible application where there are literally thousands of different things you can do. Creative application of batch scripts and EXE files used in conjunction with RHS – that gives you the power to automate your task at will – allows you to accomplish wonders through remote computing.
Case Scenario (RHS with VNC)
Used in conjunction with a program like VNC (Virtual Network Computing), Reverse HTTP Starter (RHS) can be quite effective. Assume you are at work, behind a corporate firewall and they only have ports 80 (Web), 21 (FTP) and 22 (SSH) open. Since VNC uses ports 5500 and 5900 (or the like) you would have to 'tunnel' through port 22 using an SSH (Secure Shell) client like Putty and can then easily and securely connect to your home computer. But what if you're at home and need to connect to your work computer? You can't run a VNC server on your work PC because it listens on ports that are not open in your corporate firewall. Even if you used tunneling, you will still need your office proxy server to forward the incoming connection to your work PC which is in the local area network (LAN). Asking your system administrator to do this for you might not go very well either (if you can though, then that's great). Fortunately, VNC supports 'reverse connections' which means that you can run a ‘listening daemon’ (program running silently in the background) on your home PC and merely need to initiate the connection from work so you can control the work PC from home. That seems fine until you realize that you're not actually at work when you need to connect to it from home!
The reverse connection supported by VNC can easily be scripted to run automatically and saved as a batch file. This batch file can then be executed using Windows Scheduler (at a specific time or interval) or perhaps you could even find some way to constantly ‘push’ the connection using a combination of other batch files. This means you strive to keep the connection between your work and home computer open all the time. The thing is, you don't need the reverse connection to always be active (this is possibly a security risk too) and neither do you need it to run at a specific time or date. What you need is for the reverse connection to be established when you want it. This means that you somehow need to be able to tell your computer that 'now is the time' to execute the batch file (which initiates the reverse connection). This is where RHS comes in. Most people have an account on their office server to use. Accessing this Web server from your work PC is usually very fast and you should also be able access the server from home as well. In other words, there is a 'bridge' between work and home that is equally visible and accessible to both computers via the Internet (port 80). RHS checks automatically with your Web server for a text file marker which you will upload when and only when you want the batch file executed.
Now, you might think that constantly uploading a text file 'marker' to your office Web server is a tedious task. Not so! It too can be scripted and at the click of a button (on your home PC) the file can be uploaded, modified and even deleted. Sometimes, the Internet connection between your work and home PC isn't very good so you can just relax until the connection has been properly established before deleting the marker. The illustration below shows what we mean.
General Idea of Reverse HTTP Starter
Step By Step
The following example is how to setup a workable reverse connection using RHS in conjunction with VNC on Windows XP. Listed below is what you will typically need.
Cygwin is a Linux-like environment for Windows. It allows you to perform port tunneling with SSH encryption so the remote connection is secure and not compromised. It acts as an SSH server running on one of your machines. In this case your home computer. There is an easy guide on how to install it here.
Next, you need to install and use Putty (an SSH client) on your work PC. In the ‘Session’ category, you will have to enter your home PC's IP address or host name and select the 'SSH' radio button. Even if you have a dynamic IP connection at home (i.e. your IP always changes) you can easily use a dynamic DNS update client for this purpose and just use your domain name for the IP.
In Putty, under Connections>SSH>Tunnels, you need to set it up with a source port of 5500 (depending on your VNC client) and the destination of your local machine (127.0.0.1). This means that putty will tunnel stuff from port 5500 of your computer to port 22 and encrypt that data before sending it. This 'stuff' is your work PC's desktop interface which you want to be able to control from home. Most VNC clients work with ports 5000+ and for security purposes this needs to be tunneled through port 22 which is reserved for SSH. Organizations will most likely leave port 22 open in their proxy server as compared to anything like 5500. Save the session in Putty with a specific name so every time it's called upon, it knows what to do.
At this point, you can already establish the connection from work to home. Make sure Cygwin is running as a server on your home computer and that you have a VNC listening daemon running there too. The listening daemon comes as part of the VNC package. It is essential for a 'reverse' connection. Ordinarily, you would run the VNC server on your work PC and connect to it directly from home using the VNC viewer but since your work PC is probably on a LAN behind a proxy server that won't forward incoming connections on a VNC port to your particular machine in said LAN, you have to resort to a reverse connection.
Now, back to your work PC. You can already establish the reverse connection by simply executing the session you saved on Putty and running the VNC viewer to connect to your localhost (127.0.0.1). A window of your Work PC should now pop up on your home computer. Fantastic!
Unfortunately, you probably won't be in your office when you need this connection activated. You will most likely be at home. Initiating the connection from work and then leaving it that way is not a good idea in that the connection can, and does, break at any time for any number of reasons. The only way is to initiate the reverse connection when you want by using batch scripts. The batch script to initiate the reverse connection can look something like the following. You open up notepad and save the following type of information with a *.bat extension. You will need to change certain things like file paths depending on your computer's configuration.
cd\
c:
cd program files
cd putty
START putty -l yourlogin -pw yourpassword yourhomepcip -L 5500:127.0.0.1:5500
SLEEP 30 'this is just a delay command to give time for the connection to establish
cd\
c:
cd program files
cd tightvnc
winvnc -kill 'this kills any running instance of VNC so it doesn't conflict
SLEEP 10
cd\
c:
cd program files
cd tightvnc
START winvnc -run 'starts your VNC viewer
SLEEP 10
cd\
c:
cd program files
cd tightvnc
winvnc -connect 127.0.0.1 'connects to your localhost
EXIT
This is where Reverse HTTP Starter comes in. If you have access to a HTTP server at your office you can write another simple batch file to FTP upload a marker (i.e. a text or html file) there which carries in it your keyword(s). Setting up Reverse HTTP Starter to check for this text file and its keyword(s) will allow you to initiate the batch script above remotely, when you need to. This FTP batch file (you keep this on your home PC for easy uploading of markers) can look something like what you see below.
d:
cd data
cd _misc
cd batch files
cd rvnc marker
cd up1 'up to this point, we are finding the correct path to the file
ftp -s:uscript.ftp yourftphost 'this initiates the ftp upload script which works in conjunction with this batch file
EXIT
You will need an upload script (in this case, 'uscript.ftp') to control the FTP itself automatically. It can look like this. You can take certain measures (usually described in detail on sites that teach how to create FTP batch files) to make sure the password is not as easily visible.
yourftplogin
yourftppassword
cd public_html 'usually where you upload http accessible files
cd folder1/folder2
put testfile.txt
disconnect
quit
The text file marker needs to be in the same directory so it can be uploaded to your HTTP server via FTP. Another batch file like this should be created to delete the marker once the connection has been established so it doesn't create more than one reverse connection per session. You could also insert a few extra lines of code in one of the batch files on your work PC to do this for you after having read the marker once. These FTP batch scripts are used to make the process of uploading and deleting markers as easy as the click of a button. A summary of the processes is given in the diagram below. The numbers indicate the ports typically used and arrows, the flow of data.
Processes in a Reverse VNC Connection
Security Issues
When dealing with networks and remote administration, please exercise caution and do not expose yourself or your organization to attacks from hackers and crackers. If you organization has strict policies about such connections, please inform them first.
Do not abuse Web servers by using a very low interval (e.g. 1 or 2 seconds) because you will be identified in the logs and maybe even banned from using the server.
Always backup your critical data and test your batch files are working properly in a safe environment before using them with RHS or any other program.
Troubleshooting
Why can’t Reverse HTTP Starter access my Web server URL?
Check to see if the URL has been entered correctly and that it exists. It must point directly to a *.txt or *.html file – something with readable ASCII characters.
Make sure your firewall is not blocking the program and port 80 is open.
If you see something in the URL Contents window, that means a
connection has been attempted and information returned.
Proxy server problems.
If you find that Reverse HTTP Starter is unable to connect to the Internet (port 80) because you are behind a corporate proxy server, you might consider using a free program such as HTTP-Tunnel alongside it which will facilitate the connection.
Due to the many different implementations and security settings
proxy servers might have, a third party program to suit your particular needs
(like the one mentioned above) is recommended.
I’m told there’s a problem with my batch files.
Read carefully what the error message says.
Make sure that the path is correct and the batch file(s) exist, work and can be accessed.
The path should not contain an ampersand (‘&’). Try moving the batch file(s) to a different folder or renaming the folder.
The files should not be on a network drive. Move it to a local
folder on your computer.
The ‘URL Contents’ window does not display fast enough.
Access to the server may be slow.
Your interval may be too short.
Tips & Tricks
The URL does not necessarily have to point to a *.txt file. RHS can also read *.html and any other file format so long as the text characters within it are readable. The best way to know for sure is to 'Test' the URL of a particular file type and see the, 'URL Contents' window. If the keyword is shown there then it is most likely readable. However, to make things easy, a *.txt file is usually preferred at the URL.
The concept is simple. The *.txt file at the URL should contain only 1 keyword. If it contains more than one of the keywords, only the first one (in the, 'Keyword 1' field) is read and its corresponding batch or *.exe file executed. This means that you need to replace the text file with another one (that perhaps contains Keyword 2) if you want a different batch or *.exe file executed. This can be done easily using an ftp batch script.
The path of the batch or *.exe file to be executed should not contain an ampersand ('&') because RHS may not work correctly with it - especially for batch (*.bat) files. For example, if your batch file is in the folder, "C:\batch\office & home\task1.bat" it may not work. Renaming the folder to "officehome" should fix it.
You can press the, 'Test' button to perform one check to see if everything is in order and works before actually pressing the, 'Start Checking' button. If everything is okay, you should see the contents of your URL in the window and should also have your batch or *.exe file executed one time.
If for some reason it doesn't work, this could be due to a number of issues.
Your firewall or proxy server is blocking the RHS application from accessing the Web. Simply allow it through (use a tunneling program if you have to).
The batch or *.exe file location is incorrect. Check this carefully.
If it is a batch file, you may not have written it correctly. Many times you need to make sure the path it searches within the batch file itself is correct. The best way is to execute it manually from the command prompt so you can see if there are any errors. It will tell you if there are.
The keyword(s) were not typed correctly. This means RHS isn't looking for the right word.
RHS comes with a text file called, 'rhs.txt'. In this file, you can enter all the parameters that usually need to be entered manually into the program. This will speed up the process of getting started once you have become familiar with all your settings. More information can be found via, Help>How To Use 'rhs.txt' in the menu.
The program minimizes to the system tray and runs silently in the background so you can start and then forget about it. Remember that in the shareware version, it only performs 75 checks, however. The registered version keeps checking indefinitely or until stopped.
Up to three different batch files and/or executable files can be executed with this program. However, if you need more the batch files themselves can always be scripted more effectively to accommodate the extra files. You can find out more here.
Since v1.5, there is an 'autostart' feature in the options. If you select this, the next time you start RHS it will automatically read your 'rhs.txt' file and start checking. You can also have it run when Windows starts.
Download The Latest Reverse HTTP Starter PDF
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