You cannot call Transaction SMGW.
The syslog contains an entry similar to the following:
SMGW Q0I Operating system call getservbyname failed (error no. 0 )
SMGW D01 Transaction Canceled GW 056 ( sapux090 sapgw0 )
The corresponding work process trace contains the following entry:
M ***LOG Q0I=> NiPGetServByName: service 'sapgw0' not found: getservbyname [niuxi.c 521]
M *** ERROR => ThGwMonSetGwhost: GwMonCheckGateway failed [thxxgmon.c 2111]
M ***LOG R68=> ThIRollBack, roll back () [thxxhead.c 12304]
The service specified here may vary.
If you call a function module from the SGWY function group with incorrect values for the gateway host or gateway service, this value is no longer reset after you execute the program.
As a workaround, restart the work processes. This initializes the gateway host and gateway service in the work process with the correct values, and it is once again possible to connect to the gateway.
The error is solved as of the following patch levels:
For Release 4.6D: 2128
For Release 6.40: 93
For Release 7.00: 26