Problem in HA Configuration and ERS installation

[Former Member]

Dear Experts,

I have planned to install a HA SAP ECC 6.0 System with Oracle DB.

I completely configured 5 Virtual Machines for this purpose, and at status quo, I have decided to install these components as mentioned below:

VM1: ASCS

VM2: ERS

VM3: DB

VM4: CI

CM5: DI

All machines run Redhat linux x64.

I started with installing ASCS on the first VM. It was successful; also I have configured the file system as described in the following link:

http://help.sap.com/saphelp_nwpi711/helpdata/en/27/44f17a26a74a8abfd202c4f5dc9a0f/content.htm

Then I tried to install ERS on the second VM (VM2).  The installation was able to find the profile which the ASCS has generated but finally it failed because it couldn't find some files:

sapinst_dev.log says:

TRACE      2014-03-02 15:00:23.858

NWException thrown: nw.noExecutableFound:

Cannot find executable sapcontrol at these locations: /usr/sap/SHP/ERS10/exe/sapcontrol, /usr/sap/SHP/SYS/exe/run/sapcontrol, /usr/sap/SHP/SYS/exe/uc/linuxx86_64/sapcontrol.

As a result, I decided to try another plan by installing another ERS on the first VM and it completed successfully.

Now, I have ASCS and ERS on the VM1, but I cannot install ERS on the VM2.

The question is:

1.Since I don’t want to have any SPOF, which one of the following solutions is correct?

• Solution 1:
  • VM1: ASCS
  • VM2: ERS

• Solution2
  • VM1: ASCS + ERS
  • VM2: ERS   

• Solution 3
  • VM1: ASCS + ERS
  • VM2: ASCS + ERS

2.If you dont choose Solution 3 then; How can I solve the problem of installing ERS on the second node? Any idea

Regards,

Meysam Kermani

[Former Member · Accepted solution]

check if all you have assigned proper hostnames, IP address and maintain all the VM host entry details in /etc/hosts file of VM2.

DB is a SPOF and you should identify how you will eliminate this in your solution. also look into how you will make the /sapmnt/<SID> filesystem a high available one

regards,

Chandru

[Former Member]

In solution 3, do they need to configure virtual IP address for ERS? or ERS doesn't need virtual IP address?

- Jinkoo

[isaias_freitas]

Hello Jinkoo,

The ERS itself does not receive any connections. So, it does not need a virtual IP in any case.

However, you should not have two ASCS instances running at the same time (as solution 3 suggests).

The best approach is to have the ASCS in cluster.

Then, you can decide whether to install one ERS at each cluster node and use scripts triggered by the cluster to control which ERS is the active one (it should be the ERS not running at the same cluster node as the ASCS) or you could put the ERS in cluster as well.

The cluster should then control where the ERS is running (should be at the cluster node where the ASCS is not running).

See Polling Concept - Standalone Enqueue Server - SAP Library for the cluster scripts concept. Your cluster partner should help with (or provide) the scripts.

Cheers,

Isaías

[Former Member]

Hi Kermani,

looking to your issue anyhow you are not able to install a single standalone ERS on VM2, hope I'm right.

Go for third solution and see how it behaves.

Regards,

Deepanshu Sharma

[Former Member]

Hello all,

Recently I was installing consolidation system follow architecture which we use for all our production systems.

Linux host #1 : NFS, Database and ASCS

Linux host #2 : ERS

Linux host #3 : Primary AS

Linux host #4 : Secondary AS

During ERS installation I got the same error as you:

"Cannot find executable sapcontrol at these locations: /usr/sap/exe/sapcontrol..."

It seems that sapinst did not create some things properly so I will write what I have done.

From OS level ,on VM where ERS will be installed please execute:

cd /usr/sap/<SID>

mkdir SYS

cd SYS

mkdir exe gen src

ln -s /sapmnt/<SID>/global global

ln -s /sapmnt/<SID>/profile profile

cd exe

mkdir opt

ln -s /sapmnt/<SID>/exe/uc/linuxx86_64 dbg

ln -s /sapmnt/<SID>/exe/nuc nuc

ln -s /usr/sap/<SID>/SYS/exe/dbg run

ln -s /sapmnt/<SID>/exe/uc uc

Then click retry in your window installation.

I hope that it would help.

Regards,

Karolina

[Former Member]

no idea about the topic?

[Former Member]

do you want to install the SAP on HA (High availability/SPOF)?

as per your thread looks like you want to install each service on separate VM?

I would strongly suggest you must go through the installation guide and before you start the installation check whats your requirement is. for example refer https://service.sap.com/~sapidb/011000358700001414082012E