Configuration for Central SLD in HA

[Former Member]

Hello Experts,

We have our central SLD system (ABAP+JAVA) 7.31 in HA with ASCS/SCS and DB as SPOF and clustered and CI as non clustered component.

The physical host for ASCS/SCS,DB and CI/ DI  are different . Currently for connecting to SLD the satellite systems uses CI-host and 5<instno>00 as port  , which does not makes it High Available as if CI goes down SLD won't be reached .So my questions are :

1)How to make sure the SLD is Highly Available if CI goes down as CI is not in HA and we do not plan to take CIinto HA.

2)We want to use ASCS/SCS host and gateway for connecting to SLD. How this can be achieved. As the same gives error in SLDAPICUSTand RZ70. Although for CIhost it worksfine butthanits not Highly available.

Using SAP webdispatcher for load balancing can be aoption but in that case whatsettings would be required for RZ70. If anyone of you have had similar situationand solution pleasedo suggest.

Regards,

Umesh

[TomCenens]

Hi Umesh

Do you have standalone gateway?

ref: 1678705 - Installation scenarios for a standalone ASCS instance

Kr

Tom

[Former Member]

Hello Tom ,

Thanks for the reply ,

I have gw services up and running for my both ASCS and SCS instance which are on a separate host than PAS . However the connection fails when I use ASCS/SCS virtual host and SCS instance number in RFC 's in satellite system as well as in RZ70 .

Based on your blog how to push ABAP data to java only SLD . I checked the data supplier paramters(sld-administration-settings-all) ,currently it has settings of PAS and its gateway .

So would like to make it ASCS/SCS virtual host and SCS gatway service (sapgw<SCSinst no>.

Since my central SLD system is a dual stack system. This way the rfc connections will be load balanced based on available app server .

Although my dought is if i make the changes and take a sld server restart will it effect any SAPSLDAPI rfc's in satellite system where currently we have mentioned the gateway host and service of PAS.

For SLDAPICUST we are planning to use a proxy to load balancer (for ex sapwebdispatcher type) and route the same to available application server .

Please suggest if this would help us in making SLD HA

Regards,

Umesh

[TomCenens]

Hi Umesh

I don't know, I would need to research it myself so I can't help you out on this right now nor do I have time in the near future to research it.

So I would suggest you contact SAP with this question if you don't get the answer from within the community.

Kr

Tom

[Former Member]

Hi Tom ,

Thanks for the update .

Will do check with SAP and will post the solution here .

Thanks for your time.

Regards,

Umesh

[former_member187148]

Hi Umesh,

Could you please post the response from SAP or how did you fix this error?

[Former Member]

Hello Sreenath ,

Although I opened the message to SAP but before they replied I resolved on my on .

For my case the gw/acl_mode = 0 parameter was not active on one of the profiles of ASCS/SCS and hence was facing issue . After maintaining the parameter the issue resolved .

Please do let me know what is your scenario and accordingly will help you achieve it .

Regards,

Umesh Patel

[former_member187148]

Thanks for the response Umesh.

The trouble i have is very similar. I have PAS/SCS/ASCS on one host (clustered) and AAS for PI

We wanted to acheive high availability which means that if PAS is down, we should be able to function without issues.

I have SLD running on the gateway of SCS, but when i stop PAS and login to PI through Load balancer URL -> SLD registration is RED.

The error I get is "No System Landscape Directory registered"  and "Unable to read data from SLD; details: com.sap.lcr.api.cimclient.CIMClientException: IO error: Unable to open connection to host "<PAS host>:51100". The host is down or unavailable.."

I changed all the places where PAS was hard coded to LB URL but still having one place where it is pointing to PAS

[Former Member]

Hello Sreenath ,

Please check SAP Note 1052984  .

1)Please do let me know where all places you have mentioned the SLD details . (SLDAPICUST, RZ70  and Under SLD - Administration - Data Supplier what is maintained

2) what is maintained in your gw security parameters for PAS ,SCS, ASCS

3)What does your load balancer URL point to -- I mean virtual host of cluster or something else ?

4)Also do let me know the places where you have already maintained the load balancer URL .

Regards,

Umesh

[former_member187148]

I have followed the note -> 1052984 - Process Integration >=7.1 - High Availability

ABAP

RZ70

SLDAPICUST

SLD_UC

LCRSAPRFC

SAPSLDAPI

SLDCHECK works fine

JAVA -> NWA

1)SLD Data Supplier has the LB URL

2)SLD client has LB URL

We are not using ASCS for GW ; we are using SCS. So, we have gw/acl_mode turned off. (value '0')

LB URL is a F5 URL which has virtual pools and http, https access points

LB URL is maintained as per SAP Note

[Former Member]

Hello Sreenath,

In which profile have you maintained the gw/acl_mode parameter .

Please check under gwmon pf = <SCS profile > do you see SLD_UC , SLD NUC registered with LB url or with PAS physical host .

You can also do some test --

Register a test program in your PI under Java - NWA - JcoRFC Provider

Under Server Configuration - Gateway Host -- Put LB  and Gateway service - sapgw<SCS Inst No >

Under Repository Configuration --      Application Server Host -- localhost and service as sapgw$$

save it and check if its running .

Now In any test backend ABAP system create a RFC similar to SAPSLDAPI and give program name as the one you just created in JcoRFC provider .

Gateway -- LB

Service  -- sapgw<SCSInstNo>

Do a connection test , if everthing is fine than you are not dependent on PAS .

Regards,

Umesh

[former_member187148]

Hi Umesh - my issue is not with the RFC's. All the RFC's are working fine and I have SLD programs running on the gw of message service.

There is still one last thing which is going to PAS. I am not able to find what it is... the logs doesnot say the name of the JCO connection but just say RFC communication failure

[former_member187148]

This is the exact error

"

Caused by: com.sap.aii.utilxi.sld.XISldException: IO error: Unable to open connection to host "p11:51100". The host is down or unavailable..

at com.sap.aii.utilxi.sld.MRSldProxy.loadComponents(MRSldProxy.java:1072)

at com.sap.aii.utilxi.sld.MRSldProxy.loadSld(MRSldProxy.java:1025)

at com.sap.aii.utilxi.sld.SubSystemFactory.createSldFromSld(SubSystemFactory.java:569)

at com.sap.aii.utilxi.sld.SubSystemFactory.createSldFromSld(SubSystemFactory.java:611)

at com.sap.aii.rwb.agent.server.SLDAgentBean.buildSLD(SLDAgentBean.java:767)"

[Former Member]

Hello Sreenath ,

Can you tell me where are you getting this error , as you said sldcheck was running fine .

Also once check your loadbalancer url is configured properly from the network team .

Regards,

Umesh

[Former Member]

Hi ,

Please also check what is mentioned under your PI SLD -- Administration -- Settings - Instead of Default select data supplier and check what is maintained for gateway host and service .

Caution : - If you change the gateway host and service here you need to restart the SLD to make it effective .

Regards,

Umesh

[manumohandas82]

Hi Umesh ,

You can use the ASCS/SCS  Virtual hostname in RZ70 to connect   [ The port should be ASCS/SCS  http port ] .

You might be getting the rror as the virtual hostname  Virtual ip is not  aaded to /etc/host file or DNS .

You can implement the same by a webdispatcher also but not needed in most cases

Thannks ,

Manu

[Former Member]

Hello Manu ,

I tried the same but it does not work . I tried giving the virtual hostname of ASCS/SCS and gateway for sapgw<SCSinstNo> / or sapgw<ASCSinstNo> but it failes . Although it works fine if I give CI host and gatway.

Everything is maintained in /etc/hosts file regarding virtaul hostname .

Regards,

Umesh

[manumohandas82]

Hi Umesh ,

Lets use the ASCS for the message server connection  .

Can now you try to configure once again in RZ70 using Message server virtual  hostname  [ ASCS ] and  ASCS port  [ Find from SMMS goto parameters ] and send the error screenshot .  gateway should sapgw [Instance number of ASCS ]

Gateway security settings - extra information regarding SAP note 1444282 - Application Server Infras...

1434117 - Bypassing sec_info without reg_info

Thanks ,

Manu

[Former Member]

Hello Manu ,

Thanks for update .

Although I have gone through this notes and also have tried  setting  the parameter gw/acl_mode = 0 dynamically , but it did not helped much.

Just for testing in SM59 . I created a RFC similar to SAPSLDAPI and provided it with a registered test program which is running on the SLD system under Jco RFC provider now under this RFC   when I give gateway host and service of ASCS/SCS host it terminates with  the error message as below

Connection Error

Error when opening an RFC connection (CPIC-CALL: 'ThSAPOCMINIT' : cmRc=2 thRc=67

ERROR: Transaction program not registered

LOCATION: SAP-Server <PAS-HOST>_<SID>_15 on host <PAS-HOST> (wp 7)

COMPONENT: CPIC

COUNTER: 6

MODULE:

LINE:

RETURN CODE: 679

SUBRC: 0

RELEASE: 721

TIME: Mon May 18 10:22:42 2015

VERSION:

Although If I give PAS host it works fine .

The program registered at SLD end in Jco RFC proivder runs with either PAS Host and corresponding gateway  or  with hostname as - localhost and sapgw$$. But does not run with ASCS/SCS virtual host and gateway.

This is the reason i think the above RFC fails , but could not understand how to make it work.

Regards,

Umesh