PortServer IP Address and TCP Port

The wizard will attempt to connect to a PortServer at the Address and TCP port number that you supply. If it cannot connect, you will see several error messages, but you will be able to proceed with the RealPort driver configuration. Before you can use the RealPort driver, however, you must determine the reason the wizard could not connect:

•	You should verify that you are using the correct IP address and TCP Port number.

•	You should check the Event Log to see if an error is recorded.

  IP Address

 TCP Port


Name of PortServer and Number of Ports

Use this window to:

•	Provide a name for the PortServer to which you will connect using the RealPort driver.

If you do not type a name, the wizard will supply a default name. You can change the name at a later time by accessing the PortServer Properties window.

•	Verify the number of ports you will use.

The actual number of ports found on your PortServer is displayed. You can change this value to a number less than the actual number of ports if you do not plan to access all of the available ports using the RealPort service. You can later add or remove ports by accessing the PortServer Properties window.

Note: You can also install more ports than actually exist on your PortServer, but you will not be able to use them.


What to do next?

At this point your configuration is complete:

•	Click the Finish button to see the Digi RealPort Service Setup window.

•	To immediately change the default names of the PortServer ports, check the appropriate box and then click on Finish.

•	If you want to make changes to the PortServer name, the number of ports, and/or the IP Address and Port number, click Back until you get to the right screen, or click Finish and access this information through the PortServer Properties window.


PortServer Properties: Ports
PortServer Properties: Ports PortServer Properties: Ports

This window provides a numerical list of the ports available on the PortServer and shows the name assigned to each port number. Note that this is different from the main window which lists the ports by name only.

•	You can change the names of the ports by clicking the Properties button and typing a new name in the Name field of the window that displays.

•	You can add a port by clicking the Add button.

•	You can remove a port by highlighting the port you want to remove and clicking the Remove button.


Working with a Port

You can add a port or change the default name of a port at any time:

•	To change the name of an existing port:

Type a new name in the Name field.

Example: if port 5 has a printer attached, you may wish to change the name to “Printer”.

•	To add an additional port:

Type the number of a port in the Port field and a name in the Name field. (or accept the default Add Port values by clicking the OK button.)

Note: If you change these fields using the Properties button, you will be changing the existing values, not adding new ones.

More about ports


PortServer Properties: PortServer

 Name

 IP Address

 TCP Port

 Poll cycle

 Max packet size


Digi RealPort Service Setup Window

This window displays the PortServers configured for your system and all of the ports configured for use on each PortServer. Click on the + to expand the list. Click on the - to collapse it.

To add a new PortServer

To add a port to an existing PortServer

To remove a PortServer

To remove a Port

To examine the properties of a PortServer

To examine or change the properties of a Port

To rename a PortServer or Port


To add a new PortServer

1	Highlight the system icon in the Digi RealPort Service Setup window.

2	Click the Add button.

3	The Add PortServer Wizard will start.

Note:

You must know the IP Address and TCP Port number of the PortServer you want to add.

  Related Topics


To add a port to an existing PortServer

1	Highlight the PortServer to which you will add a port.

2	Click the Add button.

3	You will see the Add Port window display.

4	Accept the defaults by clicking the OK button, or edit the fields you want to change and then click OK.

More about ports


To remove a PortServer

1	Highlight the PortServer you want to remove.

2	Click the Remove button in the window or the Delete key on your keyboard.

Note:

If the PortServer is in use when you remove it, all users will get disconnected with no warning.


To remove a Port

1	Highlight the port you want to remove.

2	Click the Remove button in the window or the Delete key on your keyboard.

Note:

If a device attached to the port you remove is in use when you remove it, all processes will get disconnected with no warning.


To examine or change the properties of a PortServer

1	Highlight a PortServer icon and then click the Properties button, or double-click on the PortServer icon.

2	The PortServer Properties window will display.

3	From this window you can make changes to the PortServer and its associated ports.


To examine or change the properties of a Port

1	Highlight a port and then click the Properties button, or double-click on the port name.

2	The Port Properties window will display.

3	From this window you can change the name of any port.


To rename a PortServer or Port

Highlight a PortServer or Port name and then click on it once to get a cursor. Type in a new name,

or

Highlight a PortServer or Port name and then click Properties to use the PortServer Properties or Port Properties window to make the change.


About the PortServer IP Address

The PortServer is assigned an IP address using the "set config ip" command from a terminal attached to the PortServer.

To find out the IP address of a PortServer, you can issue a "set config" command to the PortServer; all configuration information, including the IP address will display on the terminal.


About the PortServer TCP Port number

The default TCP Port number (set at the factory) is 771.

To find out what the current setting is, you can use the "set config" command to display the current configuration. Look for the value next to the "realport" (PortServer II) or “netcx” (PortServer) entry.

Note:

The TCP Port Number can be changed by issuing a "set config realport" (PortServer II) or “set config netcx” (PortServer) command via a terminal attached to port 1.


Name Field

The current name given to the PortServer at this IP address is displayed in this field. You can change the name at any time by typing a new name in this field.

You should use a name that uniquely identifies the PortServer. For example, the PortServer location or its function could be used.


IP Address Field

You must provide the IP Address of the PortServer in this field.

To find out the IP Address, you can issue the "set config" command to the PortServer via a terminal attached to its port 1; a list of its configuration parameters will display.


TCP Port Field

You must provide the TCP Port number of the PortServer in this field. The default TCP Port number is 771.

If you are having trouble connecting to the PortServer using the default of 771, you should check the actual TCP Port setting on PortServer by issuing a "set config" command to the PortServer from the terminal attached to it. Look for the number next to "realport" (PortServer II) or “netcx” (PortServer).

Note:

The TCP Port number can be changed by issuing a "set config realport" (PortServer II) or “set config netcx” (PortServer) command via a terminal attached to port 1.


Poll Cycle Field

The Poll Cycle is the number of milliseconds the RealPort Service will wait for additional data to make a full packet (as defined by Max Packet Size) before sending the packet to the PortServer. If the Poll Cycle time elapses and the packet is not full, the packet is sent anyway.

Depending on your system setup, you may wish to increase the default value to cause less traffic on the network.

Valid Poll Cycle range is 10 to 1000 milliseconds.


Max Packet Size Field

The default Max Packet Size value (1460) optimizes RealPort Service for TCP/IP over Ethernet. You should only change the default if you are using media other than Ethernet.

Max Packet Size is the number of bytes of data that the RealPort Service will put into a packet. To keep overhead to a minimum, this value must be the same as or smaller than the data portion of the MTU (Maximum Transmission Unit) of the media that carries the packet to the PortServer. (If the Max Packet Size is greater than the data portion of the MTU, all of the data in a RealPort packet will not fit in a single media packet, leftover data must be sent in a second packet, and traffic over the media will increase.)

Example MTU packet structure for Ethernet:

MAC 	    14 bytes
IP(V4)	    20 bytes
TCP	    20 bytes
TCP Data	1460 bytes
FCS	    04 bytes

Total MTU size = 1518 bytes

Allowable Max Packet Size range is from 3 to 65,535 bytes.


More about ports

•	Ports on the PortServer are physically labeled with the number of the port, starting with 1. The PortServer itself has 16 ports, but you can have up to 64 ports available if you add expansion modules to the base PortServer. Each of the PortServer ports is assigned a default system name during RealPort  installation: COM2, COM3, COM4, etc.

•	Ports do not need to be added or maintained in sequence. You can change the Port field to any valid port number. For example, you may use ports 1 through 8 for modems and port 26 for a printer. If those are the only ports you use, you can shorten your list by deleting unused ports.