Coexistence: Preserve or migrate a Version 5.1 gateway
Web services gateways running on WebSphere Application Server Version 5.1 can, subject to certain restrictions, coexist with gateway instances running on Version 7.0 or later application servers. Alternatively, we can migrate the Version 5.1 gateways and application servers to WAS v7 or later. To help you choose whether to preserve or migrate the Version 5.1 gateways, this topic explains the restrictions to gateway coexistence and the approach taken to gateway migration.
WebSphere Application Server Version 5.0 is no longer supported, so you should migrate any existing gateways that are running in Version 5.0 application servers to run on application servers at the current level of the product.
Coexistence with Version 5.1 gateways
Version 5.1 web services gateways can coexist with Version 7.0 or later gateways, subject to the following restrictions:
- The Version 5.1 web services gateway application is not supported on Version 7.0 or later application servers.
- The service integration technologies endpoint listener applications are not supported if installed on Version 5.1 application servers.
- To change the configuration of a gateway running on a Version 5.1 application server, you use a web browser rather than the console to access the Version 5.1 gateway user interface.
If the deployment is not affected by these restrictions, and the Version 5.1 gateways are running on stand-alone Version 5.1 application servers, then we need take no further action.
If the deployment is not affected by these restrictions, and the Version 5.1 gateways are running on Version 5.1 application servers that are part of WAS Network Deployment cells, we can continue to use the Version 5.1 gateways and application servers even if you migrate the cells from Version 5.1 or Version 6 to Version 7.0 or later. However, when you migrate a cell any previously-configured Version 5.1 gateway on an application server in the cell is replaced with an empty gateway. To preserve and restore the Version 5.1 gateway configurations, first follow the steps given in Preserve a Version 5.1 gateway when migrating a cell.
Migration of Version 5.1 gateways
We can migrate a Version 5.1 gateway running in a Version 5.1 application server to a Version 7.0 or later gateway running in a Version 7.0 or later application server. To do this you export the Version 5.1 gateway configuration, then run a script to migrate the exported configuration into a new gateway instance in an existing Version 7.0 or later application server. The detailed steps for this task are given in Migrate a Version 5.1 web services gateway configuration. The key rules underlying the migration process are as follows:
- The migration can happen in parallel with the original gateway continuing to run, and without disrupting the existing configuration.
- Each execution of the migration command acts on a single gateway configuration.
- A gateway configuration is migrated into a gateway instance, within a service integration bus. More than one gateway can be migrated into the same bus, but in that case the gateway namespace URIs must be different.
- The endpoint listeners for the gateway instance are all located on the same application server or cluster; localizations of port destinations for outbound invocation are all in the same application server or cluster.
- All created objects and destinations have the gateway namespace URI as a prefix to their name, concatenated with a colon (":"). For example with the default namespace URI, a gateway service reply destination would be called: urn:ibmgateway:gatewayservicenameReply. This prefix can be overridden by a parameter on the migration command.
- All target services are migrated into new OutboundService objects. Existing OutboundService objects cannot be automatically reused by the migrated configuration.
- A JAX-RPC handler list is created for every gateway service/channel and gateway service/target service/port combination. These are not shared even if they contain the same handlers in the same order.
- WS-Security (Draft 13) configuration and binding objects are created for every gateway service/gateway service and target service combination. These are not shared even if they have all the same attribute values. All created objects have names based upon the name given to the inbound or outbound service created by the migration tool:
- The WS-Security configurations created for each service are given the same name as the service itself, suffixed by either _Inbound or _Outbound.
- The WS-Security configuration objects created as children are given the same name as the type of object, followed by _x, where x is the number of objects the migration tool has created of the type for the service. For example the first Required Integrity object created for a given service is called RequiredIntegrity_1.
- The WS-Security bindings created are given a name consisting of the port name, suffixed by the type of binding, one of _Req_Rec, _Req_Snd, _Res_Rec and _Res_Snd.