HTTP : Logon load Balancing : Webdynpro

[Former Member]

Dear All,

Apologies for putting same blog again for common topic.

I checked many blogs but unfortunately I am still stuck with logon load balancing functionality. May I have some expert opinions on this.

I want to configure logon load balancing HTTP requests using Message server.

Scenario -

As per Help.sap.

http://help.sap.com/saphelp_nw04/helpdata/en/28/75153a1a5b4c2de10000000a114084/content.htm

Prerequisites - are already present.

Parameter

ms/server_port_0 = PROT=HTTP,PORT=81$$ is set and

The ICF Services sap/public/icf_info/logon_groups and sap/public/icf_info/urlprefix must be activated (transaction SICF),

are already activated.

SMLG - logon group is created.

When I provide "Logon group" in SICF services, for example (webgui) and test logon load balancing its giving below URL.

http://<message server host>:<ms http port>/<service path>/<service name>

Which do not work 

If we modify respective URL with domain as below , logon load balancing works fine.

http://<message server host>.<domain>:<ms http port>/<service path>/<service name>

Does anyone have any idea from where parameter <domain> is picking and how its working.

little hint, may be helpful.

Thanks,

Regards,

Bond

[tobias_winterhalter]

Hi 007,

Also check parameter SAPLOCALHOSTFULL and make sure that the server's IP is resolved by the DNS into the full name including domain. You can verify this with the command:

niping -v -H <messageserverhost>.<domain>.com

Best, Q

[Former Member]

Dear Tobias,

We have concept of virtual hostname with different host name for  physical server.

As i check niping to virtual host name.

niping -v -H <messageserverhost>

output is as below -

Hostname of local computer: <phyiscal hostname>                  (NiMyHostName)

Lookup of hostname: <physical hostname>                            (NiHostToAddr)

    --> IP-Addr.: <IP of physical host>

Lookup of IP-Addr.: <IP of physical host>                             (NiAddrToHost)

    --> Hostname: <physical hostname>.<domain>.com

Lookup of hostname: <virtual host>                               (NiHostToAddr)

    --> IP-Addr.: <IP of virtual host>

Lookup of IP-Addr.: <IP of virtual host>                             (NiAddrToHost)

    --> Hostname: <virtual hostname>.<domain>.com

full host name entry is returning.

Any idea ?

Regards,

[Former Member]

Dear Tobias,

SAPLOCALHOSTFULL is defined in DEFAULT.PFL file , does it need to be in instance profile or default is fine ?

more DEFAULT.PFL | grep -i SAPLOCALHOSTFULL

SAPLOCALHOSTFULL = $(SAPLOCALHOST).$(SAPFQDN)

Regards,

[tobias_winterhalter]

This looks good.

Check the parameter ms/http_domain: Message Server Parameters - Monitoring and Administration of the SAP Message Server - SAP Library

The default value of 1 means: The domain after the redirect is the same as used to access the MS.

So, if you enter URL http://<mshost>:<msport>/abc, it will redirect to http://<appserver>:<httpport>/abc.

And if you enter URL http://<mshost>.<domain>.com:<msport>/abc, it will redirect to http://<appserver>.<domain>.com:<httpport>/abc.

You can force MS to always add the domain by setting ms/http_domain = 0.

Best,

Tobias

[Former Member]

Thank you Tobias, i will check and update you

[Former Member]

Dear Kn. Tobias,

Good morning,

we tried ms/http_domain = 0 , as it is a dynamic parameter.

Although , respective parameter says its changing value but in RZ11 current value still shows as 1 , even after changing to 0.

We tried changing in RZ11 and re-test respective SICF -> WEBGUI -> Load balance test.

URL is unchanged and it is still showing as http://<mshost>:<msport>/abc 

Seems like a mystery to me now.

Regards,

Bond

[tobias_winterhalter]

This is a bug in RZ11. The parameter value is indeed changed dynamically, but the display in RZ11 is not updated 😞

After you set ms/http_domain to 0, did you also try to enter http://<mshost>.<domain>.com:<msport>/abc in a browser? I assume this is the real use case The test from SICF might have other issues.

Best,

Tobias

[Former Member]

Dear Tobias,

Yes, after setting ms/http_domain to 0, we tried http://<mshost>.<domain>.com:<msport>/abc in browser and it was working. This was working fine earlier also the one http://<mshost>:<msport>/abc  is not working.

Can you kindly let us know after right clicking does it show "http://<mshost>.<domain>.com:<msport>/abc"  in your system or by experience ?

Thanks for your help so far.

Regards,

[Former Member]

Hi james,

please check this parameter icm/host_name_full.

Regards,

Chandu

[Former Member]

Dear Chandu,

below parameter is already set.

icm/host_name_full = <messageserverhost>.<domain>.com

[Former Member]

HI,

It will check for the parameters ,depending on it URL weblink is works

1)icm/host_name_full

2)SAPGLOBALHOST

3)SAPLOCALHOSTFULL

[Former Member]

Dear Sandeep,

URL work , but I have to manually insert .<domain>.com into it , then it works fine.

1) icm/host_name_full = <messageserverhost>.<domain>.com

2) SAPGLOBALHOST = <messageserverhost>

3) SAPLOCALHOSTFULL = <messageserverhost>.<domain>.com

are these correct ?

any idea ?

[Sriram2009]

Hi Bond

Could you refer the SAP Note

1040325 - HTTP load balancing: Message Server or Web Dispatcher?

and SCN link about http load balancing

http://scn.sap.com/people/pise.mangesh/blog/2011/08/19/load-balancing-abap-webdynpro-services

BR

SS

[Former Member]

Hi Bond,

Yes. Kindly Cross Check above parameters ,as all are maintained properly or not .If not modify accordingly. once these are setted automatically it will open web gui in the format :

• http://<messageserverhost>.<domain>.com:80XX/sap/bc/gui/sap/its/webgui

And also Cross verify below steps too

Step 1: Verifying the configuration parameters for ICM.

Use Transaction SMICM (ICM Monitor).
Displays the ICM configuration and monitoring. Make sure it is running. Check the following ICM parameters.

[Menu-> Goto -> Parameters ->Display]

1. icm/server_port_0 PROT=HTTP,PORT=8000
2. icm/host_name_full <Full Qualified Domain Name>

  I will use the domain name as testp1.bomain.cpstl 

Following parameters should be checked.

Step 2: Activate Required Services:

Following 3 services need to be enabled.

1. /default_host/sap/bc/gui/sap/its/webgui
2. /default_host/sap/public/bc/ur
3. /default_host/sap/public/bc/its/mimes

  Use Tcode ‘SICF’ to enable services. Then execute it to show the services trees. 

Then activate the mentioned services according to the below guide.

1. /default_host/sap/bc/gui/sap/its/webgui
2. /default_host/sap/public/bc/ur
3. /default_host/sap/public/bc/its/mimes

Right click on the relevant service and then activate it.

Step 3: Publishing Services:

Run T-Code SIAC_PUBLISH_ALL_INTERNAL  to activate the services. Will take few minutes. While running it will show the status message like:

Finally the following screen can be seen.

Thanks & Regards,

Sandeep

[Former Member]

Thanks Former Member for detailed explanation.

Although, as I check all settings are already present still its only picking below when I right click and select "Load balancing" option on service "webgui".

• http://<messageserverhost>:80XX/sap/bc/gui/sap/its/webgui

And when I modify and put .domain.com manually it works fine and points to application instance.

all 3 SICF services -

1. /default_host/sap/bc/gui/sap/its/webgui
2. /default_host/sap/public/bc/ur
3. /default_host/sap/public/bc/its/mimes

Ran T-Code SIAC_PUBLISH_ALL_INTERNAL to activate all services , it activated around 211 services.

now when I try to test service webgui with option "Load balancing"

it maps only <messageserverhost>

but when I click on "Test Service" for same service I get fullhostname

<messageserverhost>.<domain>.com

regards,

[Former Member]

Dear Bond,

can you resolve <message server host> name on you local computer?

With best regards,

Alexander

[Former Member]

Hi Former Member

sorry but can you give more details about

can you resolve <message server host> name on you local computer?

Thanks,

[Former Member]

Dear James,

You can open command line box and perform command:

ping <message server host>

If you receive you cannot resolve this name, the name not registered in DNS server or you local host file.

With best regards,

Alexander

[Former Member]

Dear Alex,

Ping hostname returns servername.domain.com. As i checked with DNS entries , it is already present over there.

## ping <messageserverhost>

PING <messageserverhost>.<domain>.com (virtual ip) 56(84) bytes of data.

64 bytes from <messageserverhost>.<domain>.com (virtual ip): icmp_seq=1 ttl=64 time=0.027 ms

64 bytes from <messageserverhost>.<domain>.com (virtual ip): icmp_seq=2 ttl=64 time=0.022 ms

64 bytes from <messageserverhost>.<domain>.com (virtual ip): icmp_seq=3 ttl=64 time=0.021 ms

Regards,

Bond