Enabling JSOR communication between a Java application and a native application (Linux only)

To enable Java™ sockets over Remote Direct Memory Access (JSOR) communication, you must first ensure that the native application is using the RSockets protocol. The RSockets protocol can be used by preloading the native RSockets preloading library or by using RSockets APIs to write the native application. Start of changes for service refresh 2 fix pack 10 Support for NIO channel applications is added in this update. End of changes for service refresh 2 fix pack 10

Before you begin

For an overview, read JSOR native interoperability (Linux only).

About this task

Note:

Start of changes for service refresh 8 fix pack 30

The RDMA implementation, which was previously deprecated is removed from IBM® SDK, Java Technology Edition, Version 8. End of changes for service refresh 8 fix pack 30

End of changes for service refresh 8 fix pack 30

There are two methods for enabling JSOR communications between a Java application and a native application. You must select the correct system property for your application. For example, plain stream socket applications (com.ibm.net.rdma.conf) or NIO channel applications (com.ibm.nio.rdma.conf).

Procedure

Follow these steps if you want to communicate by preloading the native RSockets preloading library:
1. If you are connecting a JSOR client with a native server, type the following command-line invocation:
```
java -Dcom.ibm.net.rdma.conf=<client.conf> -cp <classpath> SampleClient <client_args>
```
```
LD_PRELOAD=/usr/lib/rsocket/librspreload.so ./SampleServer <server_args>
```
  Or:
```
java -Dcom.ibm.nio.rdma.conf=<client.conf> -cp <classpath> NIOClient <client_args>
```
```
LD_PRELOAD=/usr/lib/rsocket/librspreload.so ./NIOServer <server_args>
```
  Where:
  - client.conf is your client RDMA configuration file.
  - classpath specifies the class path.
  - client_args are the client application-specific command-line options.
  - server_args are the native application-specific command-line options.
2. If you are connecting a JSOR server with a native client, type the following command-line invocation:
```
java -Dcom.ibm.net.rdma.conf=<server.conf> -cp <classpath> SampleServer <server_args>
```
```
LD_PRELOAD=/usr/lib/rsocket/librspreload.so ./SampleClient <client_args>
```
  Or:
```
java -Dcom.ibm.nio.rdma.conf=<server.conf> -cp <classpath> NIOServer <server_args>
```
```
LD_PRELOAD=/usr/lib/rsocket/librspreload.so ./NIOClient <client_args>
```
  Where:
  - server.conf is your server RDMA configuration file.
  - classpath specifies the class path.
  - server_args are the server application-specific command-line options.
  - client_args are the native application-specific command-line options.
Follow these steps if your native application is written to use the RSockets APIs to communicate with a JSOR client or server application:
1. If you are connecting a JSOR client with a native server that is written to use the RSockets APIs, type the following command-line invocation:
```
java -Dcom.ibm.net.rdma.conf=<client.conf> -cp <classpath> SampleClient <client_args>
```
```
cc -o SampleServer -lrdmacm
```
```
./SampleServer <server_args>
```
  Or:
```
java -Dcom.ibm.nio.rdma.conf=<client.conf> -cp <classpath> NIOClient <client_args>
```
```
cc -o NIOServer -lrdmacm
```
```
./NIOServer <server_args>
```
  Where:
  - client.conf is your client RDMA configuration file.
  - classpath specifies the class path.
  - client_args are the client application-specific command-line options.
  - server_args are the native application-specific command-line options.
2. If you are connecting a JSOR server with a native client that is written to use the RSockets APIs, type the following command-line invocation:
```
java -Dcom.ibm.net.rdma.conf=<server.conf> -cp <classpath> SampleServer <server_args>
```
```
cc -o SampleClient -lrdmacm
```
```
./SampleClient <client_args>
```
  Or:
```
java -Dcom.ibm.nio.rdma.conf=<server.conf> -cp <classpath> NIOServer <server_args>
```
```
cc -o NIOClient -lrdmacm
```
```
./NIOClient <client_args>
```
  Where:
  - server.conf is your server RDMA configuration file.
  - classpath specifies the class path.
  - server_args are the server application-specific command-line options.
  - client_args are the native application-specific command-line options.

Results

Regular TCP/IP socket calls are intercepted and replaced by the equivalent RDMA socket calls for talking to remote applications through the RDMA path.