Need advise when install a Distribute System

[Former Member]

I want to install SAP ERP 2005 SR2 ABAP (Oracle) on Linux such as Distribute System

I have two server so called server A and server B

I read document for Installation Guides but I donu2019t understand following issue :

And my questions :

When I run ./SAPINST -> SAP ERP 2005 SR2 -> SAP System -> Oracle -> Distribute Sysem -> Based On AS ABAP include

+ Global Host Preparation

+ Database Instance

+ Central Instance

Question 1: I donu2019t understand concept Global Host Preparation ? Itu2019s purpose ?

Question 2:I donu2019t know where Global Host Preparation install (sever A or server B)?

And then where Database Instance install (Server A or Server B)?

And finally Central Instance (Server A or Server B)?

Question 3: When install a Distribute System completely, do I need to install more a Dialog Instance ?

thanks for your advise ....

[Former Member]

Hi !

After installation a Distribute System on Server A, B completely, so called Site Primary. For any reason, Site Primary down. For this reason, I want to setup a difference site in another place, so called Site Standby (standby for Site Primary). In this Site Standby, I have two server, so called server C and D. And my questions

Question 8: On server D - I want to setup a standby database Oracle for server B (server B is primary database). Can I do it ? How by ? for example: I install more a Database Instance with anythings same server B (etc u2026 DBSIDu2026)?

Question 9: And finnally, on server C, I install a Central Instance with anythings same sever A. Can I do it ?

Thanks your advise

[Former Member]

Hi

The concept that you are trying to use is High Availability System. There is a difference between HA system and a distributed system. You separate SAP components in Distributed system for sake of administration and hardware load. It noway provides you high availability option. whereas a HA model has distributed systems within it but they are also highly available as per your requirement.

SAP supports HA model but you have to get that solution from certified vendors like microsoft, HP etc. You will need to have all essential components (DB, SCS,ASCS) on cluster so that if one node is down, services will be automatically start on other. That concept is totally different and so is the approach.

Kindly be more specific on your requirement. The more I see into it, the more I feel that you are searching for Cluster fundamental in distributed systems which is wrong.

Regards,

Javed

[Former Member]

Hi

In the model Distribute System, i have more any questions following :

Question 4: Can i install Central Instance and Database Instance in the same server (ex: server B) ?

Question 5: If i install Central Instance and Database Instance in the same server (ex: server B), On the server A - Do I can install more a Dialog Instance or a Central Instance ? Does Central Instance exist unique ?

Question 6: Can i install Central Instance and Dialog Instance in the same server (ex: server A) ?

Question 7: When Central Instance doesn't start, but Dialog Instance and Database Instance had started -> can client login to SAP system ?

thanks for your advise

[Former Member]

Question 1: I donu2019t understand concept Global Host Preparation ? Itu2019s purpose ?

Answer: Global Host is the Host Where SCS and ASCS instances are installed. They contain message server and enque for ABAP and Java Respectively.

Question 2:I donu2019t know where Global Host Preparation install (sever A or server B)?

Answer: You can have global Host in ServerA

And then where Database Instance install (Server A or Server B)?

Answer: ServerB

And finally Central Instance (Server A or Server B)?

Answer: Any (A or B) . If you have additional hardware then Install it on Separate one. As such there is no restriction.

Question 3: When install a Distribute System completely, do I need to install more a Dialog Instance ?

Answer: As said above, it all depends on your expected load.

Question 4: Can i install Central Instance and Database Instance in the same server (ex: server B) ?

Answer: Sure! It is possible technically. It is only divided so as to reduce load on the server load due to both DB and CI usage.

Question 5: If i install Central Instance and Database Instance in the same server (ex: server B), On the server A - Do I can install more a Dialog Instance or a Central Instance ? Does Central Instance exist unique ?

Answer: There can just be one Central Instance in a System. So if you install Central Instance on Node B, then you can only install Dialog instance in Other node,

Central Instance is unique in the sense that it has SDM, visual admin and configtool in it, which is missing in dialog instance.

Question 6: Can i install Central Instance and Dialog Instance in the same server (ex: server A) ?

Answer: Yes. You can install as many dialog instance as you want, only that your hardware should be capable of handling it.

Question 7: When Central Instance doesn't start, but Dialog Instance and Database Instance had started -> can client login to SAP system ?

Answer: Yes. Client can login in Server as long as Global Host Server , database server and any other instance (CI or dialog) is up. Only that if CI is down, you cannot do administrative work for Java. (Remember SDM, Visual Admin and configtool will be unavailable)

Hope this answers your question.

Regards,

Javed

[former_member759680]

Question 7: When Central Instance doesn't start, but Dialog Instance and Database Instance had started -> can client login to SAP system ?

Answer: Yes. Client can login in Server as long as Global Host Server , database server and any other instance (CI or dialog) is up. Only that if CI is down, you cannot do administrative work for Java. (Remember SDM, Visual Admin and configtool will be unavailable)

Correct me if I am wrong, but isn't the dispatcher on CI?

How will the system start if CI is down?

Thanks.

[Former Member]

Dispatcher is persent on every instance!!

So if your global Host is up , you got message server and when any of the instance is up, you got a dispatcher.... what else do u need to connect!!!!

[former_member185031]

>>Question 1: I donu2019t understand concept Global Host Preparation ? Itu2019s purpose ?

Global host is nothing just CI in a distributed environment. Its called globalhost becuase this host should be accessed by DB and DI server also, so the kernel directory and trasn directory is global directory of this server as per my understanding.

>>Question 2:I donu2019t know where Global Host Preparation install (sever A or server B)?

Server A

>>And then where Database Instance install (Server A or Server B)?

Server B

>>And finally Central Instance (Server A or Server B)?

Server A

>>Question 3: When install a Distribute System completely, do I need to install more a Dialog Instance ?

>>thanks for your advise ....

Nope. If the hardware is not enough to handle the user request then only you will have to install a dialog instance.

Regards,

Subhash