Communication line of SerialOverUDP Device Redundant, SerialOverUDP Line Redundant and SerialOverUDP System&Line Redundant categories

SerialOverUDP Device Redundant, SerialOverUDP Line Redundant, and SerialOverUDP System&Line Redundant communication lines were designed for support of "Serial to Ethernet Device Servers" of NPort series. (e.g. Moxa NPort serial devices). These devices are the powerful compact switches converters of RS232/422/485 interfaces on to the TCP/IP Ethernet which support work in UDP mode. These devices transmit data, received from serial linelines, to UDP packets, and send them to one or more IP addresses and ports (where the D2000 KOM process localityis located). Likewise, NPort the serial device server sends data, which have been received on specific UDP port, to a serial port.
The transmission parameters of the serial line are set in the configuration of NPort the serial device and cannot be changed or set through via configuration in the D2000 System. Data, transmitted in UDP packets between NPort the device and D2000 KOM, contain only data of the serial communication. They contain neither the control nor the check characters (e.g. handshaking).
Note: a RFC2217 Client line can be used to control the parameters of the serial line if the serial server supports the RFC2217 mode.

Kotva
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SerialOverUDP Device Redundant communication line

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This line supports a redundancy of NPort serial devices servers and also working in D2000 Redundant System when the if used communication protocols, supporting a redundancy, are used support redundancy of application server.

Configuration parameters

• Local Port

It is a UDP port,

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to which the KOM process is bound and

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where the data from

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the serial

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server is received. Local Port must correspond

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to the serial server configuration (the parameter Port in the line where IP address with KOM process is set). A local UDP port must be a unique, neither another line nor any application (out of D2000 System) can use it.

• Primary Device - Port

IP address or hostname of

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a serial

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server. It is a UDP port

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that receives

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the data transmitted by the D2000 KOM process. The Port value must correspond to

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the serial server configuration (the parameter "Local Listen Port").

• Kotva
  backup_device backup_device

  Use Backup Device

Check this option if you use a redundant configuration of

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the serial servers.

• Backup Device - Port

IP address or hostname of a backup

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serial server. It is a UDP port

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that receives

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the data transmitted by the D2000 KOM process. The Port value must correspond to

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the serial server configuration (the parameter "Local Listen Port").

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The Serial Device Redundancy and D2000 System Redundancy

The most simple way to design NPort Device Redundancy is a linking on RS485 interface Serial device redundancy can be most easily implemented by connecting the RS485 interfaces of serial servers for the half-duplex protocols. The half-duplex protocols are all which use a request/response principle, which are is basically almost all protocols for the asynchronous serial interfaces.

Some of the communication protocols support  support D2000 System Redundancy in the set of where there are more instances of KOM process (KOM process HS on HOT server and KOM process on SBS server). In that case, a communication process , connected to the SBS server , never send sends data and cancel doesn't interfere with the communication of the KOM process connected to HS the HOT server. Its function is only listening on the receiver from NPort deviceIt only listens and processes the data received from the serial server. If it is possible, it analyzes these data.

If the KOM process was started in D2000 System Redundancy and watches HS it follows the HOT server (start parameter /RD or /RF), all the communication protocols, supported on the communication line of "SerialOverUDP Device Redundant communication line" type, operate in D2000 redundant system.

Switching between the primary and backup device

A primary device is used after starting the KOM process in case of NPort device the redundant configuration of the serial servers. A backup device starts to work when any no message with data has not been detected from the primary device up to within a defined timeout (a default value is 15 seconds, but you it can change it be changed for some of the protocols in the protocol parameters). All data polls are sending requests start to be sent to the backup device. If the communication via the backup device works good, the primary device is not testedchecked any more. If the communication with a backup device fails, it will be switched back to the primary device. Basically, the devices always switch after a detection of the communication error on the working device.

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Examples of configuration

This is a simple connection of the NPort device which replaces the an asynchronous serial port directly in PC. No redundancy is used including NPort devices, D2000 System and the network interfaces.

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The parameters:

• TCP/IP network: 192.168.0.0/16
• The IP address of NPort serial device: 192.168.0.50
• The IP address of D2000 server with KOM process: 192.168.0.1.

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Operating Mode dialog box - the configuration of the NPort serial device:

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The port 4001 is set was chosen for Local Listen Port. Data are sent to D2000 KOM process 192.168.0.1, which uses also the local port 4001. We recommend to use the same port number within the configuration of one communication line.

The configuration of the D2000 communication line is the same as NPort device configuration:

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This is a dual redundant connection of NPort devices without D2000 System Redundancy and Ethernet network infrastructure.

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The configuration of NPort 1 and NPort 2 must be the same as it is mentioned in the Example 1.

D2000 communication line uses the backup device NPort 2:

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This is the complete redundant system consisting of NPort device redundancy, D2000 System Redundancy and dual network infrastructure.

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The parameters:

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Operating mode dialog box - NPort 1 configuration:

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NPort 2 configuration:

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The above-mentioned settings show that both NPort devices send data to both D2000 servers (i.e. KOM processes), to IP addresses in that network in which it is connected (NPort 1 in Ethernet A and NPort 2 in Ethernet B).

Both NPort devices (primary and secondary one) are set in the D2000 communication line configuration:

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This configuration is complete completely redundant and resistant to failure of any dual deviceredundant devices as well as the failure of one of the redundant network segments.

Kotva
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SerialOverUDP Line Redundant communication line

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This line is quasi "dual" SerialOverUDP Device Redundant line. It is intended for those communication protocols with defined the transmission on via two redundant physical transmission lines. The For the configuration of this line is category, the same rules apply as for the configuration of SerialOverUDP Device Redundant line.

Kotva
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SerialOverUDP System&Line Redundant communication line

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This line is like "double line of "SerialOverUDP Line Redundant". It is specially used for the communication protocols with defined transmission towards two remote systems. The communication works with each of them on , two redundant physical serial lines. The transmission lines to each (or a single remote system with four lines).  For the configuration of this line is category, the same rules apply as for the configuration of SerialOverUDP Device Redundant category line.

Note: The line is supported for communication protocols used in the main and backup electro-energy dispatching of SED - SEPS.

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