Configuration Errors
All Configuration Errors
Symptom
The configuration
status is shown under window Landscape à
Connectivity: Tab page
RFC/Current as either yellow 
or 
red.
Meaning
The RFC configuration is inconsistent. There are inconsistencies either in the TREX system or between the TREX system and the SAP system.
Action
...
1. Choose Repair All.
This function
corrects all configuration errors for which automatic correction is possible.
This can take several minutes. During this time, the configuration status
remains yellow or red.
Do not choose Repair All several times in quick succession. This would trigger reconfiguration more than once and delay the correction of errors.
2. Check the progress by choosing Refresh to update the display.
3. Check whether any configuration errors remain that require manual intervention. Correct these manually.
We recommend always choosing Repair All first and only correcting configuration errors individually that require manual intervention.
It does not make sense to correct only selected configuration errors. However, the TREX admin tool provides this option, if you require it in special circumstances.
In the following section, you can find information about all configuration errors that can occur.
Local SAP Gateway: Application Server Cannot Reach the TREX System
Symptom
An RFC connection
has the status red. When you
select the RFC connection, the lower half of the window displays the
following:
● One or more cells in the table are red.
● These table cells contain the message <local gw>, GW down or network problems.
Meaning
The application servers are running and using their local SAP gateways for the RFC connection. The application servers are specified in the TREX configuration. However, at least one application server cannot reach the TREX system. Possible causes are:
● The local SAP gateway of the application server is not available.
● There are network problems.
Action
...
1. In the lower window area, select the table cell that displays the message.
2. In the context menu, choose Remove App Server.
This action does not solve the cause of the error. However, you can avoid unnecessary TREX trace files.
Once the cause of the error is solved (for example, the SAP gateway is available again), this is reported to the TREX system. The Landscape RFC window then provides the option of adding the application server to the TREX configuration again.
Local SAP Gateway: Application Server Is not Registered in the TREX Configuration
Symptom
An RFC connection
has the status yellow or red. When you select the RFC connection,
the lower half of the window displays the following:
● One or more cells in the table are yellow.
● These table cells contain the message <Local GW>, Not set in TREX.
Meaning
There are application servers in the SAP system that are not registered in the TREX configuration. Possible causes are:
● The TREX system has not been configured after installation.
● New application servers have been added to the SAP system.
● For example, the application could not reach the TREX system due to network problems and were removed from the TREX configuration. In the meantime, the application server can reach the TREX system again.
Action
...
1. In the lower window area, select the table cell that displays the message <Local GW>, Not set in TREX.
2. In the context menu, choose Add App Server.
Central SAP Gateway Is not Available, But Is Registered in the TREX Configuration
Symptom
An RFC connection
has the status red. When you
select the RFC connection, the lower half of the window displays the
following:
● One or more cells in the table are red.
● These table cells contain the message GW not available, but set in TREX.
Meaning
The SAP system and the TREX system communicate through a central SAP gateway. The SAP gateway is registered in the TREX configuration, but is not available. Therefore, the application servers cannot reach the TREX system.
Possible cause: The gateway information in the RFC destination contains typing errors.
Action
...
1. In the lower window area, select the table cell that displays the message GW not available, but set in TREX.
2. In the context menu, choose Remove GW Host.
This action does not solve the cause of the error. However, it helps to avoid unnecessary TREX trace files.
When you refresh the display, the following message appears:
GW is nonexistent, inactive or inaccessible – manual repair required
3. Check whether the SAP gateway is started and whether it is accessible through the network.
Once the cause of the error is solved (for example, the SAP gateway is available again), this is reported to the TREX system. The Landscape RFC window then provides the option of adding the SAP gateway to the TREX configuration again.
4. If necessary, switch to another SAP gateway.
For more information about the procedure, see Changing the Central SAP Gateway.
Central SAP Gateway: Network Problems
Symptom
An RFC connection
has the status yellow
or red. When you select
the RFC connection, the lower half of the window displays the
following:
● One or more cells in the table are yellow.
● These table cells contain the message:
GW set in TREX, GW available. Network problems?
Meaning
The SAP system and the TREX system communicate through a central SAP gateway. The RFC configuration is correct in both systems and the SAP gateway is available. Nevertheless, the application servers cannot reach the TREX system.
Possible cause: There are network problems.
Action
Attempt to correct the network problems. Configuration changes are not necessary.
Central SAP Gateway Is not Registered in the TREX Configuration
Symptom
An RFC connection
has the status yellow
or red. When you select
the RFC connection, the lower half of the window displays the
following:
● One or more cells in the table are yellow.
● These table cells contain the message GW available, but not set in TREX.
Meaning
An SAP gateway that is not registered in the TREX configuration is entered in the RFC destination.
Possible cause: The TREX system has not been configured after installation.
Action
...
1. In the lower window area, select a table cell that displays the message GW available, but not set in TREX.
2. In the context menu, choose Add GW Host <...>.
3. Repeat both steps for all cells that this message appears in.
Central SAP Gateway Is not Available
Symptom
An RFC connection
has the status yellow
or red. The following
message appears:
GW is nonexistent, inactive or inaccessible – manual repair required
When you select the RFC connection, the lower half of the window displays the following:
● One or more cells in the table are yellow.
● These table cells contain the message GW not available and not set in TREX.
Meaning
An SAP gateway that is not available is entered in the RFC destination. The TREX system and the SAP system cannot communicate through this SAP gateway.
Possible causes are:
● The gateway information in the RFC destination contains typing errors.
● The SAP gateway has not been started.
● The SAP gateway cannot be reached on the network.
● The SAP gateway is temporarily unavailable, for example, due to maintenance.
● The SAP gateway is permanently unavailable, for example, because the host has changed.
Action
...
1. Check the gateway information in the RFC destination.
To do this, use transaction SM59 in the SAP system.
2. Check whether the SAP gateway has been started.
3. Check whether the SAP gateway can be reached on the network.
4. If necessary, switch to another SAP gateway.
For more information about the procedure, see Changing the Central SAP Gateway.
RFC Destination not Available in the SAP System
Symptom
The following message is displayed:
No TREX relevant RFC Destination in SAP System
Meaning
The TREX admin tool can connect to the SAP system. RFC destinations are registered in the TREX configuration. However, there are no RFC destinations of the same name in the SAP system.
With regard to RFC destinations, you must ensure the following:
● The RFC destination exists in the SAP system.
● The name of the RFC destination that is specified in the TREX configuration matches the name in the SAP system.
Action
...
1. Check the name of the RFC destination in the SAP system.
To do this, use transaction SM59 in the SAP system.
2. Check the name that is specified in the TREX configuration.
To do this, use the TREX admin tool (stand-alone), Landscape RFC window, RFC Destinations function.
More Than one External Application Uses the Same RFC Destination
Symptom
An RFC connection
has the status red. The
following message appears:
Another application is also using this RFC destination – manual repair required
When you select the RFC connection, the lower half of the window displays the following:
● One or more cells in the table are red.
● These table cells contain the message Not set in TREX, but TREX reachable.
Meaning
In the SAP system, there is an RFC destination that is used by more than one external application. The reason is probably that there is more than one TREX system that is connected to the same SAP system and uses the same RFC destination.
With this configuration, the SAP system cannot distinguish which external application it sends the requests to. It is possible that the wrong external application receives the requests.
Action
If the external applications in question are only TREX systems, proceed as follows:
...
1. For each TREX system, check which RFC destinations are specified in the TREX admin tool. To do this, use the RFC Destinationsfunction in the Landscape RFCwindow.
2. Make sure that the RFC destination that is used more than one is specified in only one TREX system.
3. Make sure that there is a separate RFC destination in the SAP system for each TREX system.
If the external applications in question are not only TREX systems, proceed as follows:
...
1. Make sure that there is a separate RFC destination in the SAP system for each external application.
2. Configure the external applications so that each one uses the RFC destination assigned to it.
For a TREX system, use the RFC Destinationsfunction in the Landscape RFC window to do this.
For other external applications, you can find the procedure in the documentation of the application in question.
Unnecessary Application Servers in the TREX Configuration
Symptom
The following message is displayed:
App Servers in TREX that belong to none of the connected SAP Systems
Meaning
There are application servers specified in the TREX configuration that do not belong to the SAP system. Possible causes are:
● An administrator has removed the application server from the SAP system.
● An administrator has deleted the RFC destination in the SAP system.
Action
...
1. Select the message App Servers in TREX that belong to none of the connected SAP Systems.
The lower half of the window displays the superfluous entries.
2. Remove the entries from the TREX configuration. To remove an entry, select it and choose Remove App Server from TREXDaemon.ini on all TREX hosts in the context menu.
Faulty Gateway Instance or Program ID in the TREX Configuration
Symptom
The following message is displayed:
App Servers/GW hosts in TREX with wrong instance or service
Meaning
The configuration of one or more TREX RFC servers is incorrect. Either the gateway instance is incorrect or the program ID that these TREX RFC servers use to register with the SAP gateway. Due to the incorrect configuration, these TREX RFC servers cannot receive requests from the SAP system.
Action
...
1. Select the message App Servers/GW hosts in TREX with wrong instance or service.
The lower half of the window displays the incorrect entries.
2. Remove all incorrect entries from the TREX configuration. To remove an entry, select it and choose Remove App Server/ GW Host from TREXDaemon.ini on all TREX hosts in the context menu.
Unnecessary RFC Destinations in the TREX Configuration
Symptom
The following message is displayed:
RFC Destinations in TREX that belong to none of the connected SAP Systems
Meaning
There are RFC destinations specified in the TREX configuration that do not exist in any of the connected SAP systems.
Possible cause: An administrator has deleted the RFC destination in the SAP system.
Action
...
1. Select the message RFC Destinations in TREX that belong to none of the connected SAP Systems.
The lower half of the window displays the superfluous entries.
2. Remove the entries from the TREX configuration. To remove an entry, select it and choose Remove RFC Destination from topology.ini in the context menu.
Number of RFC Server Instances Is Inconsistent
Symptom
The following message is displayed:
Configured Number of RFC Servers differs from default value
Meaning
The number of started RFC server instances is different to the number defined as the default value.
Action
...
1. Select the message Configured Number of RFC Servers differs from default value.
The lower half of the window displays the connections for which there are inconsistencies.
2. Reset the number of RFC server instances to the default value as follows:
a. Select a row in the lower half of the window.
b. In the context menu, choose the option Set Number of RFC Server Instances in TREXDaemon.ini to default value on all TREX Hosts.
Program ID Is Possibly not Unique
Symptom
The following message is displayed:
Potentially non unique Program IDs detected
Meaning
This message occurs if you have created RFC destinations directly in the SAP system and not using the TREX admin tool (stand-alone).
One or more RFC destination contain program IDs that do not conform to the naming convention defined by TREX. The program IDs may not be unique. This can cause problems if more than one TREX system communicates with SAP applications using the same SAP gateways. The requests from the SAP applications could be forwarded to the wrong TREX system.
Action
...
1. Select the message Potentially non unique Program IDs detected.
The lower half of the window displays the connections that are affected by this problem.
2. Change the program ID as follows so that it is unique:
a. Select a connection in the lower half of the window.
b. In the context menu, choose the option Set Program ID to suggested value <...>.
c. Repeat both steps for all remaining connections.
The change is made in the TREX configuration and in the RFC destination in the SAP system.