Add Target-Initiated Distribution Paths

Target-initiated paths for Microservices enable the Receiver Service on the target to initiate a path connecting to the Distribution Service on the source deployment and pull trail files from the source.

To create a target-initiated distribution path:

1. Log in to the Receiver Service.

2. Click the plus (+) sign on the Receiver Service home page to start adding a receiver path.

3. The following table lists the options to set up the path:

   Table 8-1 Add a Target-Initiated Distribution Path

   Screen and Options	Description
   Path Information Screen	Provide a name and description for the target-initiated path on this screen
   Path Name	Name of the target-initiated distribution path
   Description	Provide a description of the path.
   Source Options Screen	Specify the options for the source deployment which will be connected by the target-initiated path.
   Reverse Proxy Enabled	Select to use reverse proxy. To know more about configuring your reverse proxy servers, see Reverse Proxy Support.
   Source Authentication Method	Select the authentication method for the source URI. Authentication options are OAuth 2.0, Certificate, UserID Alias.
   Source Protocol	From the drop-down list, select your data transfer protocol. The default option is Secure Web Socket Proctocl (wss). Other option is ws.
   Source Host: Domain: Enter the domain for the host. Alias: Provide an alias for this host. Path takes the source trail and sends the data to a target trail given here, which can be consumed by any Replicats created later.	Specify the URL of the source host. For example, localhost, if the source is on the same system.
   Port Number	Enter the port number of the Distribution Service.
   Trail Name	Enter the trail name you want to read on your source. NOTE: The Distribution Service doesn't not create any trail on source. It can only read the provided trail name.
   Trail Subdirectory	Specify the trail subdirectory (if any).
   Trail Size	Maximum size of the trail file that can be received from the source.
   Generated Source URI	A URI is automatically generated for the trail based on the source information you provided.
   Encryption Profile	Select the name of the encryption profile for receiving trail data. Also see Encrypting Trail Files.
   Source Authentication Method	The source authentication method is preselected based on the selection made on the source deployment.
   Domain	This option is preset to Network.
   Alias	Provide an alias for the source host.
   Begin	This option allows configuring the position from where the log data is received. The options are: Now: The current position to begin received trail data. Custom Time: Receive trail data between the specified time period. Position in Log (default): Receive trail data based on the position in log. CSN (at or after): Specify a CSN value at which or after which the trail data would be received.
   Source Log: Sequence Number	Specify a sequence number value for the source log.
   Source Log: RBA Offset	Specify RBA offset value for the source log.
   Target Options	Specify the Trail file and directory for the target deployment.
   Trail Name	Name of the target trail of the Replicat you created earlier.
   Subdirectory	Name of the trail subdirectory.
   Target Encryption Algorithm	Select the encryption algorithm for the target trail. Options include AES128, AES192, AES256.
   Generated Target URI	A Target URI is automatically generated for the trail based on target trail information you provided. Click the pencil icon, if you want to edit it.
   Change Encryption	To allow changing the encryption algorithm after the path is created, enable this toggle switch.
   Target Type	Select one of these types of trail file formats: GGFormat Plain Text XML SQL
   Advanced Options	Specify advanced network options.
   Enable Network Compression	Enable this toggle switch to specify a compression threshold value.
   Compression Threshold	Set the compression threshold value if you decide enable this option.
   Sequence Length	The length of the trail sequence number.
   Eof Delay (centiseconds)	You can specify the Eof Delay in centiseconds. On Linux platforms, the default settings can be retained. However, on non-Linux platforms, you may need to adjust this setting for high bandwidth, high latency networks, or for networks that have Quality of Service (QoS) settings (DSCP and Time of Service (ToS) ).
   Checkpoint Frequency	Frequency of the path that is taking the checkpoint (in seconds).
   TCP Flush Bytes	Enter the TCP flush size in bytes.
   TCP Flush Seconds	Enter the TCP flush interval in seconds.
   DSCP	Select the Differentiated Services Code Point (DSCP) value from the drop-down list, or search for it from the list.
   TOS	Select the Type of service (TOS) value from the drop-down list.
   TCP_NODELAY	Enable this option to prevent delay when using the Nagle’s option.
   Quick ACK	Enable this option to send quick acknowledgment after receiving data.
   TCP_CORK	Enable this option to allow using the Nagle’s algorithm cork option.
   System Send Buffer Size	You can set the value for the send buffer size for flow control.
   System Receive Buffer Size	You can set the value for the receive buffer size for flow control.
   Keep Alive	Timeout for keep-alive.
   Filtering Options	Specify rules for filtering within the trail.
   Rule Name	Name of the rule you need to create.
   Rule Action	Select from the Exclude or Include rules. Exclude would filter out based on the selected options, while Include would include data based on the specified options.
   Filter Type	Select from the following list of options: Object Type: Select from three object types: DML, DDL, and Procedure Object Names: Select this option to provide an existing object name. A 3–part naming convention depends on whether you are using CDB. With CDB, you need to use a 3–part naming convention, otherwise a 2–part convention is mandatory. 3–part convention includes container, schema, object. 2–part convention includes schema, object name. Procedure Feature Name: Select this option to filter, based on existing procedure feature name. Column Based: If you select this option, you are presented with the option to enter the table and column name to which the rule applies. You can filter out using column value with LT, GT, EQ, LE, GE, NE conditions. You can also specify if you want to have before image or after image in filtered data. Tag: Select this option to set the filter based on tags. Chunk ID: Displays the configuration details of database shards, however, the details can’t be edited.
   Object Names	Name of the object being filtered.
   Negate	Select this check box if you need to negate any existing rule.
   Managed Options	Additional options to configure auto restart.
   Critical	Enable this toggle switch if configuring auto restart options based on high availability requirements.
   Auto Restart	By default this toggle switch is enabled. If disabled, the path is not restarted automatically when killed.
   Autorestart Retries	The number of times to try an restart the task (path process).
   Autorestart Delay	The duration interval to wait between retries.

4. Click Create and Run to start the path.

For target-initiated distribution paths, the use case for the ws and wss protocols is explained in the following table:

Deployment Type	Target Deployment (Non Secure)	Target Deployment (Secure)
Source Deployment (Non-secure)	ws	ws
Source Deployment (Secure)	wss	wss

The wss protocol must be specified whenever the source deployment (Distribution Service host) has been configured with security enabled. The secured communication channel can be created using an SSL certificate in a client Wallet, even if the target deployment (Receiver Service host) has disabled security.

Features and Limitations for Using Target-initiated Distrbution Paths

Here are the limitations when working with target-initiated distribution paths:

• There is no support for interaction between legacy and secure deployments using this mode of operation for target-initiated distribution paths.

• No support for ogg protocol. Only ws and wss protocols are supported.

• It is possible to only get information and stop a target-initiated distribution path on Distribution Service and after the path stops, it is not be visible on the Distribution Service.

You can also set up target-initiated distribution paths using the Admin Client.

For command options, see the Admin Client commands ADD RECVPATH, ALTER RECVPATH, INFO RECVPATH, DELETE RECVPATH, START RECVPATH.