DMCMVFY - Run communications verifier

Use this command to test TCP/IP communications between local and remote servers.

Before replicating data, communications between the publisher and target must be operational. This command allows you to verify TCP/IP communications before starting CDC Replication data replication.

This command generates messages indicating whether the communications test was successful or not. When unsuccessful, these messages identify the cause of the problems. Messages are placed in the DMVFYCMN message queue in the current library. You can also display messages to standard output or you can redirect them to a file for future viewing. Before issuing this command, you need to make sure that a CDC Replication listener is running on the remote server with which you want to perform the communications tests.

Each communications test consists of a number of steps. You can choose to display information for each step. The steps are:

Open: Open the communication channel.
Connect: Attempt to connect to the communication channel.
Send_control: Send control information across the communication channel.
Send_data: Send actual data across the communication channel.
Close: Close the communication channel.

Applies To—Source and Target

Parameters

Table 1. Supported keywords
Keyword	Description	Choices	Notes
RMTNME	Remote server name	`Name`	Required
RMTPRT	Remote server port number	2223, `Number`	Optional
TSTTYP	Test type	PACKETS, TIMED	Optional
NBRPKT	Number of packets	5, `Number`	Optional
TIMLMT	Test duration time	60, `Time`	Optional
VERBOSE	Verbose format	NONE, LOW, MEDIUM, HIGH	Optional
LCLNME	Local server name	*DFT, `Name`	Optional
LCLPRT	Local port number	0, `Number`	Optional
PKTLEN	Packet length	512, `Length`	Optional
SNDDLY	Send delay	0, `Time`	Optional
RCVDLY	Receive delay	0, `Time`	Optional

Remote server name (RMTNME)

The host name or full IP address of the remote server in the communications test.

Name: Specifies the host name or full IP address.

Remote server port number (RMTPRT)

The port number on the remote server that is used to perform the communications test. This port number was allocated when you installed CDC Replication.

Number: Specifies the port number.; The default setting is 2223.

Test type (TSTTYP)

Specifies the type of communications test to run.

*PACKETS: Runs the test by sending the number of packets as defined for the NBRPKT parameter.; This is the default setting.
*TIMED: Runs the test for approximately the time specified for the TIMLMT parameter. This allows you to test the stability of the connection for a specified amount of time.

Number of packets (NBRPKT)

The number of packets that are sent to the remote server. This parameter is valid only when the TSTTYP parameter is set to *PACKETS.

Number: Specifies the number of packets.; Minimum Setting: 1 packet; Maximum Setting: 99999 packets; Default Setting: 5 packets

Test duration time (TIMLMT)

Specifies the duration, in seconds, of the test. This parameter is valid only when the TSTTYP parameter is set to *TIMED. The value specified for the NBRPKT parameter is ignored. When the VERBOSE parameter is set to either *MEDIUM or *HIGH, a message is displayed for every packet that is sent. This can add to the amount of time the test requires to complete, and therefore, may cause the time of the test to exceed the time specified.

Time: Specifies the duration, in seconds, of the test.; Minimum Setting: 0 seconds. The test runs continuously.; Maximum Setting: 999999 seconds; Default Setting: 60 seconds

Verbose format (VERBOSE)

The amount of information that is displayed for the test.

*NONE: Specifies that no messages are displayed during the test. A return code is generated after the test has completed.; This is the default setting.
*LOW: Displays the return code and the amount of time each step took to complete.
*MEDIUM: Displays an asterisk (‘*') for every packet successfully sent. If a packet cannot be sent, the test ends and a return code is displayed.
*HIGH: Displays a message for every packet that is successfully sent. The message identifiers the return code for every packet.

For your initial communications test, specify *HIGH to ensure the communications link is conveying each packet and to determine the amount of information in a detailed report. You can then reduce the amount of information generated for subsequent tests by specifying *LOW or *MEDIUM. If you have specified a value for the TIMLMT parameter, then this parameter should be be set to either *NONE or *LOW to make sure that the value specified for the TIMLMT parameter is respected.

Local server name (LCLNME)

The local server is the server where this command has been issued.

Name: Specifies the host name or full IP address of the local server in the communications test.

*DFT: Specifies the host name or full IP address of the server where this command is issued. This is the default setting for this parameter.; This is the default setting.

Another physical server cannot be designated as the local server by identifying its host name or full IP address. Therefore, this parameter must be set to the host name or full IP address of the server where this command is issued, or *DFT.

Local port number (LCLPRT)

The port number on the local server that is used to perform the communications test. This port number was allocated when you installed CDC Replication.

Number: Specifies the port number; Default Setting: 0. This allows the local server to use any available port number.

Packet length (PKTLEN)

The length, in bytes, of each test packet that is sent to the remote server.

Length: Specifies the length, in bytes, of each test packet.; Minimum Setting: 100 bytes; Maximum Setting: 63500 bytes; Default Setting: 512 bytes

Send delay (SNDDLY)

The time interval, in milliseconds, to wait before sending more test packets to the remote server.

Time: Specifies the time interval.; Minimum Setting: 0 milliseconds. This indicates that there is no delay between consecutive packets.; Maximum Setting: 999 milliseconds; Default Setting: 0 milliseconds. This indicates that there is no delay between consecutive packets.

Receive delay (RCVDLY)

The time interval, in milliseconds, to wait for a confirmation to be received from the remote server. This value should consider communication bandwidth and utilization.

Time: Specifies the time interval.; Minimum Setting: 0 milliseconds. This indicates that there is no delay between consecutive confirmations.; Maximum Setting: 999 milliseconds; Default Setting: 0 milliseconds. This indicates that there is no delay between consecutive confirmations.

Result

This command generates the following return codes for both types of tests:

1—Indicates that each step of the test has been completed successfully.
Non-zero—Indicates that an error occurred during the test.

Examples

DMCMVFY RMTNME(SYS1)

Verifies communications with remote server SYS1 by sending a number of packets.

Default values are used for all parameters that are not specified.

DMCMVFY
RMTNME(SYS1) RMTPRT(2252) TSTTYP(*PACKETS) NBRPKT(6)

Verifies communications with remote server SYS1 by sending 6 packets.

Packets are sent to port number 2252 on the remote server.

Default values are used for all parameters that are not specified.

DMCMVFY
RMTNME(SYS2) RMTPRT(4444) TSTTYP(*TIMED) TIMLMT(300) VERBOSE(*MEDIUM)
LCLNME(*DFT) LCLPRT(5151) PKTLEN(2000) SNDDLY(900) RCVDLY(900)

Verifies communications with remote server SYS2 by conducting a timed test for 5 minutes (300 seconds).

Packets are sent to port number 4444 on the remote server.

An asterisk for each step that is successfully completed is displayed. Packets are sent from the local server on port number 5151. The length of each packet is 2,000 bytes, and there is a 900 second delay between consecutive packet deliveries and confirmations.

Note: This command has replaced the DMVFYTCP command. For information about the DMVFYTCP command, contact your IBM® representative.