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Function documentationlgtst Test Program Locate this document in the navigation structure


You can use this program to check the active instances of your SAP system and to check existing logon groups directly at operating system level.


You can do this in AS ABAP in transactions SM51, SMMS, and SMLG.


The message server must be uniquely addressed through the specification of its host name and port. In the case of the message server port, make sure that the port number (see /etc/services, for example) assigned to the port name (sapms<SID>, whereby SID is the SAP system ID) is identical on all involved hosts.

For this reason, these details should be defined in the DEFAULT.PFL global profile:

  • rdisp/mshost = <host name of message server>

  • rdisp/msserv = sapms<SID> (optional details, naming convention)


When you call the lgtst program without any parameters, you get a list of call parameters (mandatory and optional).

To test the message server connection you should set the SAP profile parameters specified in the prerequisites. If you then enter:

lgtst -H <host name message server> -S sapms<SID>,

you get a list divided into two parts:

  • List of active SAP server instances (with services)

  • List of available logon groups (with default instances)

The following table contains the options you have when calling lgtst. Below are various examples:

Call Options lgtst


Default Value



You must specify either the profile, the SID, or mshost and msserv.

Path to profile file


System ID

-H mshost

Computer on which the message server is running.

-S msserv

Port (service) on which the message server can be reached.

-T trace file


Name of trace file

-W wait time

10000 millisecs

Wait time on network does not usually have to be changed.

-D [1|2|3]


1: Display of application servers and logon groups

2: Display of application servers

3: Display of logon groups

-N [1|2|3]


Display of SNC names of the application servers and/or the logon groups (values same as –D)

-E [0|1]

With/without information on AS Java

-G group


Displays details of group logon group

-X group [-L 1]


Displays details of group logon group; the addition –L 1 causes the output to take place with the SNC name.

-A name


Determines the SNC name of the server using the name.

-P ip,port


Determines the SNC name of the server using the IP address and port (ip,port).

-C n


lgtst will be executed n times in a row

-Y n

lgtst waits n milliseconds before each execution

RFC Load Balancing Procedure

The options -G <name>, -C n and -Y n are used to test the RFC load balancing. For more information on the RFC load balancing procedure, see Note 593058.


Standard Call

If you simply call lgtst -H <Hostname message server> -S <MS port>, the following, for example, is displayed:

using trcfile: dev_lg

list of reachable application servers


[ls3022_BIN_12] [ls3022] [] [sapdp12] [3212] [DIA ICM ]

[binmain_BIN_53] [ls0347] [] [sapdp53] [3253] [DIA UPD BTC SPO UP2 ENQ ICM ]

[is0206_BIN_53] [is0206] [] [sapdp53] [3253] [DIA BTC ]

[us0301_BIN_53] [us0301] [] [sapdp53] [3253] [DIA BTC ]

list of selectable login-classes with favorites


[HTTP] [] [3253] [620]

[PUBLIC] [] [3253] [620]

[SPACE] [] [3253] [620]

This list tells you the following information:

  • binmain_BIN_53 is the central instance of the BIN system (the message server normally also runs here, so rdisp/mshost=binmain, rdisp/msserv=sapmsBIN).

  • An instance is a dialog instance with ICM, two instances offer dialog and batch work processes.

  • For the PUBLIC logon group, the instance is0206_BIN_53 is currently recommended, for HTTP binmain_BIN_53, and for SPACE ls3022_BIN_12.

The instance list (sub-list 1) generates the message server using the logons of the individual dispatchers. The data for the logon groups (sublist 2, if it exists) is used by the SAP system to calculate load balancing (provided this has been configured; transaction SMLG).

Checking the Load Balancing Within the Logon Group RFC for 10 Calls

The prerequisite is that in transaction SMLG you defined the External RFC Permitted attribute for one logon group. The following example has a logon group RFC with this attribute.

If you enter

lgtst -H <host> -S <serv> -G RFC -C 6

you will see

Group RFC : [] [3211] [640] [TRUE] [ls3022_BIN_11]

Group RFC : [] [3253] [640] [TRUE] [binmain_BIN_53]

Group RFC : [] [3211] [640] [TRUE] [ls3022_BIN_11]

Group RFC : [] [3253] [640] [TRUE] [binmain_BIN_53]

Group RFC : [] [3211] [640] [TRUE] [ls3022_BIN_11]

Group RFC : [] [3253] [640] [TRUE] [binmain_BIN_53]

Here you can see that both servers are used alternatively for the RFC calls. The field [TRUE] specifies that the RFC load balancing is activated for this group and specifies the server the next request will be assigned to.

If you enter

lgtst -H <host> -S <serv> -G PUBLIC -C 3 -Y 1000

( -Y 1000 means one second wait time between the calls), you will see, for example:

Logon data for logon classes:


Group PUBLIC : [] [3253] [620] [FALSE]

Group PUBLIC : [] [3253] [620] [FALSE]

Group PUBLIC : [] [3253] [620] [FALSE]

You can see that no RFC load balancing is activated (FALSE). The request is assigned to the Favorite logon server. Option -X supplies all the available details of an RFC logon group. The definitions in table RZLLICLASS are displayed as well. You can also see which application servers are defined in this group. Option -X can be linked, of course, to other options such as -C and -Y to test load balancing.

If you enter

lgtst name=BIN -X RFC

you will see, for example:

Logon data for logon classes:


Group RFC : [] [3253] [620] [TRUE] [binmain_BIN_53]

group-id = 1

time to reread = 180 (seconds)

logon reread = 120 (119) (number of calls before the next read)

fav type = ROUND_ROBIN (defined load balancing procedure)

first read = 1060854803 (Thu Aug 14 11:53:23 2003)

last read = 1060854803 (Thu Aug 14 11:53:23 2003)

next read = 1060854983 (Thu Aug 14 11:56:23 2003)

appl server (name [quality,deltaquality] (server in group)

binmain_BIN_53 [999,-1]

More Information

For more information about working with RFC load balancing, see SAP Note 593058.