"Rainmail Server" works with RedHat Linux v5.2 or better. RedHat Linux can be installed on an ordinary IBM compatible PC. The hardware requirements for installing "Rainmail Server" are given below.

Hardware Requirements

* The Network and VGA cards must be Linux compatible. For a list of Linux compatible card, visit

Software Requirements

"Rainmail Server" can be installed on a system with RedHat Linux v5.2 or better. The modem and network card must be working correctly with a working installation of RedHat Linux v5.2 (or above). In the following section, we talk about various things to check before proceeding with the Installation.

If you are installing RedHat on a new machine, please remember that you can assign any IP address to the machine and any name. "Rainmail Server" recognizes these IP addresses and maintains them the same during installation. However, we recommend assigning a private IP address like "" if you are going to be connected to Internet using a dial-up medium. This would greatly enhance the security of your internal LAN.

Installing RedHat Linux

If you are installing RedHat on a new machine, here are some general guidelines you can follow to make the installation smooth:

Pre-Installation Check List

"Rainmail Server" rewrites a lot of your Linux network configuration upon installation. If you had any networking software, other than the ones installed by RedHat Linux on installation, please remember to take a back up of their configurations.

The following checklist ensures that various systems that "Rainmail Server" depends on is working. If any step fails, you can talk to your OS and/or hardware vendor to make sure that the hardware is functional.

Ensure that modem is installed and working fine by following these steps:

  1. In a new console (either xterm or a normal screen console), check that the modem device file exists by typing in

    "ls -al /dev/modem"

    If the system says that the file is not found, modem has not been installed on your machine. If the modem device exists, proceed to Step 3.

  2. Find out the COM port the modem is connected to. Then create a link from the modem device to that COM port. Suppose the modem is connected to port COM1, you can create a modem device file by typing in

    "ln -s /dev/cua0 /dev/modem" (in RedHat 5.2)


    "ln -s /dev/ttyS0 /dev/modem" (in RedHat 6.0 and above)

  3. After making sure that the modem device file (/dev/modem) is present, you can test if modem is working by using minicom. Type in


    minicom will try to initialize the modem and output the result of initialization. If you see the lines "OK", your modem setup has been correct so far.

  4. Try dialing out by typing

    "ATDP<PHONENUMBER>"where <PHONENUMBER> is a phone number you know.

    You might have to replace "ATDP" with "ATDT" if your phone only supports Tone dialing. If the modem dials out, the test has been successful. To quit "minicom", you can press "Ctrl-A", "z" and then "x".

Installation Information

Installation of "Rainmail Server" requires some information so that it can connect to your ISP and also offer many of its other facilities. Some of the information will be contained in the letter you received with the copy of this software (Please call technical support if the letter is missing). You will also require other information. The following section gives a list of all the information you will need to install "Rainmail Server" and gives a pointer to where the information can be found.

Even if you are using only a DSL, Cable Modem or Leased line to connect to Internet, we recommend that you have valid values ready for above ISP information. You can buy an additional ISP dial up account and the values as above. This way, switching from your main link to backup and vice-versa becomes real easy.

"Rainmail Server" overwrites many configuration files when installed. Normally, there will be no need to get back to your current configuration. However, if you want to get back to your current configuration, you must make a backup copy of all your cofiguration files (all files from "/etc" and "/var" directories) before installing "Rainmail Server". You can ignore this warning if you are installing "Rainmail Server" on a fresh RedHat 5.2(or up) installation.


Installation is relatively straightforward and is GUI driven. Following the given steps will ensure a trouble free and easy installation:

One word of comfort before starting with the setup program: All the parameters you enter in the setup program (with the exception of email domain name in the second screen) can be changed even after installing the software. Therefore, there is no need to be afraid of entering invalid values during the setup phase. The values can always be corrected after the software is installed. However, entering the correct value during the setup phase is recommended.

The setup program is Java based. The program will check if you have Java installed on your machine and if not, will install it from the CD. After installing Java, setup program will begin to execute. When it starts up, you will see the following screen:      

Press the "Next >>" button. You will be presented with the following screen:


If your email address is of the form "" then in this screen enter the email domain assigned to your organization. This will be present in the letter that came with the software. If you have an email domain, make sure that the check box "Use Email Domain" is checked. In this example, the name of the email domain is "icsoft".If your email address is of the form "", then you have to uncheck the "Use Email Domain" checkbox. When you do that, the email domain field becomes disabled.

After entering a value for the email domain (or not - depending on your configuration), Press the "Next >>" button.


Pressing the "<< Back" button will take you to the previous screen. Pressing the "Next >>" button will take you to the following screen: In this screen you will need to enter the name of your actual Internet domain. This would also have been provided in the letter. The default domain name is "". 


You need to change it only if your letter specified a different domain. Press "Next >>" after entering the correct value for this field. That will take you to the following screen:


In this screen, you will require to enter information about how your ISP authenticates. You can get this information from your ISP. Most ISP's support PAP and therefore the default should work fine. If you encounter any problems connecting to your ISP, you can try changing to "Login" later. Choose the default (PAP), unless you are sure that your ISP uses Login mechanism. You can also enter text to expect before sending user name, password and the "ppp" command if your ISP uses login authentication.

Press "Next >>" after you enter the correct information. That will take you to the next screen.


In this screen, you will need to enter information that will help the computer connect to your ISP. You can also specify whether you want to allow Internet access to your clients (this can be changed later too) and if your telephone needs to dial using Pulse or Tone dialing. Information about ISP User ID and Password can be obtained from your system administrator or ISP. The default for other fields give the values used by VSNL Chennai. If you use a different ISP, you will need to fill in the values from your ISP (This information can also be obtained from your ISP). Please note that you have to enter your ISP password twice. This is necessary because the password does not appear on the screen when you type it in and it is easy to make mistakes if you type it in only once.

By default, the SmartProxy included in "Rainmail Server" allows other machines in LAN to access the Internet using the server machine as a gateway. Unchecking the "Enable Smart Proxy Services" disables this access.

By default, your modem is configured to dial in the Pulse mode by "Rainmail Server". Selecting the "Tone" radio button can change this setting. After entering the value for all the fields, you can proceed to the next screen by pressing the "Next >>" button.


In this screen, you will need to enter information about your incoming POP mail server. All the information required in this screen will be supplied in the letter you received with the software. You will need to change the fields only when they do not match the ones in the letter. This is the final input screen in the setup program. If necessary, you can review your inputs by going back using the "<< Back" button.

The setup program will start installing all the required software.


A progress bar on the screen will indicate the progress of installation. At end of installation, a message box will be displayed and on pressing "OK", the "Finish" button will be enabled.


Pressing the "Finish" button completes the installation.


It is recommended that you reboot the machine after this installation. When a message box appears asking whether to reboot, save all your existing documents and press "Yes". That will automatically reboot the machine


Validating your license

There is just one more step to the installation. Even though you have a fully functional server, you will not be able to create users using the "Rainmail Server" configuration program or use the web caching proxy server to access Internet because the license to your software has not been validated. To validate your license, you must enter the password supplied in your letter in the Configuration program. To validate the license, do the following:

Start "Rainmail Server" configuration program. For detailed steps on how to do this, refer to the section named "Starting the Configuration program"

In the configuration program that comes up, select "Set Maximum Users" in the left-hand side panel. That will bring up the following screen:


In the above screen, select the radio button corresponding to the license you have purchased (If you have purchased a 25 user license, click on the 25 radio button) and enter the password supplied with the letter. Make sure that you enter the password (which will be exactly 13 characters) as given in the letter. You will have to enter it twice, once in the "Password" field and once in the "Confirm Password" field. If the password entered is valid, the system will validate your license and issue a success message.

Recommended Post Installation steps

Though the server is fully functional after the above step, it is recommended that you do the following step to increase the performance of your server. Start the configuration program (for details, please look at the section named "Starting the Configuration program" and go to the panel "Mail Check Timings"). You will see the following screen:


In the above screen enter any valid value for the two edit fields ("Enter hour of day" and "Enter minute of hour"). Please take care to not use the defaults. There are no correct values for these fields and the more random it is, the better the performance of your system will be. After entering valid values, Press the "Set" button to accept the values.

This completes the installation of "Rainmail Server".

Configuring your DSL, Cable Modem or Leased line

We will configure your "Rainmail Server" to work with these devices by establishing an (possibly virtual) interface to the DSL, Cable Modem or Leased line router. To do this, you will need to assign another IP address to your machine (this has to be on the same network segment as your router).

You will also need to know the IP address of the router. We will use the router as gateway. Finally, you will need to name this (possibly virtual) interface.

If you have only one network card, your new interface must be virtual. You can named the new interface based on the old interface. In this scenario, giving a name of "eth0:1" will do. If you have two network cards (one to your LAN and another top your router), you can give this interface a new name (like "eth1").

Once you have this information, start the configuration program using the steps given in "Starting the Configuration Program" and choose the "Select Connectivity" item on the left hand side. That will bring up the following screen:


In the above screen, select "Permanent" in the "Connectivity" field. This will enable the next four edit boxes. Enter IP address of router in the "Gateway Address" field, name of our new interface in "Gateway Device" field, our second IP address in "IP Address" field and the NetMask address in the " NetMask" field. Then press "Set" to use Cable Modem, DSL or Leased line connectivity to Internet. You will have to reboot the machine for this to take effect.

Starting the Configuration Program

Once you have installed "Rainmail Server", you can start the configuration program in GUI mode.

This will bring up the configuration program.

Testing Installation

  1. If the modem is currently connecting to an ISP, wait for it to disconnect (Do not turn off the modem).
  2. Make sure that the modem is turned on and is plugged into the telephone line.
  3. Open up Netscape browser.
  4. Type in the URL
  5. If the modem starts to dial, it means that proxy server is working properly.
  6. You can do other tests once you add users and modify configuration to suit your needs.