ERROR partner '<servername>:sapgw##' not reached

[Former Member]

Hi Folks,

We are trying to connect a standalone Java stack(SAP UCES) system to SAP ISU using an RFC.

Both the systems arein different networks and we have only opened 5XX00 port and 5XX18 port form the Java system and 36XX and 33XX port from the ISU systems. Also the entires for sapmsXX 36XX/tcp entries are added in Java system for commnicating with ISU system using the load balancing method.

When I create a JCo destination from Visual admin from Java stack to ISU system everything works fine. I can see the enty for the Java stack in the ISU system's SMGW transaction. But when I create a RFC destination from Destination in visual admin to ISU system it fails with the below error:

*Error during ping operation: Connect to SAP gateway failed

Connect_PM TYPE=B MSHOST=10.2.180.126 GROUP=SAPCE R3NAME=XX2 MSSERV=sapmsX2 P

CS=1

LOCATION CPIC (TCP/IP) on local host with Unicode

ERROR partner '10.182.17.17:sapgwXX' not reached

TIME Sat Dec 18 20:07:31 201

RELEASE 700

COMPONENT NI (network interface)

VERSION 38

RC -10

MODULE nibuf.cpp

LINE 4601

DETAIL NiBufIConnect: connection pending after 60000ms

SYSTEM CALL connect

ERRNO 55

ERRNO TEXT A connect operation on a socket is not complete.

COUNTER 3*

I have added the entries in the services file but still, I see the above error:

Telnet from Java stack to ISU on port 33XX and 36XX works fine.

One more thing we have done here is there is a IP nat for the ISU. I have already set the parameter gw/alternative_hostnames as per the note Note 148832 - IP address conversion with a firewall, Bt still it gives the above error.

Any thoughts on this issue. I feel there is some network issues, Or Can we set any parameters to over come this issue.

Regards,

Vamshi.

[Former Member]

The problem with replying is, that you seem to have already checked a lot. Well here is some more for you to try. And you definitely have to check the network, maybe response packets get lost due to nat.

Things you can try:

- increase the gateway (or message server) trace level, just to check if there is a connection reaching the gateway

- we can see you are trying a load balanced connection, could you try a direct connection to a gateway?

Connect_PM TYPE=B MSHOST=10.2.180.126 GROUP=SAPCE R3NAME=XX2 MSSERV=sapmsX2

- third you can try the connection over a saprouter, you have to add the saprouter for example in the message server field: /H/saprouterhost/S/3299/H/msgserverhost

Of course saprouterhost can be the same as msgserverhost and the port does not have to be 3299.

Cheers Michael

[Former Member]

Hi Folks,

I found the solution, We should not use the message server port to commnicate when there are IP NAT's between your servers. I tried connecting to the gateway 33XX directly instead of 36XX(load balancing) port and load balancing to happen.

This only happens when you create a RFC from Java stack to ISU. It works fine when you use the Jco Connector.

Can some one from SAP in this forum can clarifiy, Am I right saying that the load balancing will not happen when you are using a IP NAT between ISU and UCES systems. Here UCES is the client which sends the request to ISU for getting any response back.

Cheers,

Vamshi.

[Former Member]

Hi Folks,

Any Ideas!!!

Regards,

Vamshi.