Remote application server Architecture

[JPReyes]

Hi,

I have a requirement where I need to consider having an application server in a different city. This is a simple case of we either make a lot of the connections  travel through the WAN or we install a remote application server and then the only thing that travels is the communications in between the SAP instances. 

I believe the most important thing here will be the latency/speed of the link. Does anyone worked in a similar scenario that can share their experience?..

Regards, Juan

[Reagan · Accepted solution]

Hello Juan

In a setup like this what matters is the network.

We have had setups like this CI and DB in city A and 2 AS's in city B.

It works as expected (especially the performance) as the network is stable.

Also I have seen issues with the log shipping with Oracle standby databases due to bad network.

Regards

RB

[JPReyes · Accepted solution]

Thanks Reagan,

So, beside the single point of failure (Network), is there any other drawbacks with this model?...

I was thinking having 2 application servers in City B using logon balancing to prevent downtime if one of them becomes unavailable..

Regards, Juan

[Reagan · Accepted solution]

As far as I know there isn't any in addition to the network one.

Setting up 2 AS's will be a good option.

Find out few power users and few users who do not depend much on performance. Configure logon groups with these 2 AS's and make those users connect there.

Check with the users after few days. If the performance is acceptable for them and if yes then you have a good setup.

If buffering some tables can give some advantage then I could consider that as well.

Database Table Buffers - Application Development on AS ABAP - SAP Library

Buffering Database Tables (SAP Library - Tables)

Regards

RB

[Former Member · Accepted solution]

Hi Juan,

     I feel proud to share this thread with you bcoz i became fan of you by reading your articles

As per my knowledge,   

    The user's who logged in AS (City B) will feel the poor performance when they do the operations like Insert, Delete and Update bcoz the data needs to updated/deleted in the Database of the server which is in City A.

And you mentioned that adding one more AS in the same city B, Will definitely helps to avoid downtime(if one is unavailable) but may not help by means of performance as both are in same city B. Network is same so that Performance also same for one server or more.

These are my views/opinions and correct me if m wrong....

Regards

Santosh K

[JPReyes · Accepted solution]

Thanks for your input. I'm going to set up a test application server and compare the performance in between the scenarios.  I checked the latency in between the two sites and its really low which is a good thing.

This is a balancing act in between volume over the WAN or volume over the CI / AS link.

Regards, Juan

[Former Member · Accepted solution]

Hello Juan,

Have you considered about placing app servers in the Amazon Web Services (AWS). Would appreciate any inputs, if you have an compared the rough estimates of cost/efforts required between both physical install/maintain vs AWS install/maintain, which is a better option? Any insight is helpful.

Thank you

[JPReyes · Accepted solution]

Hi Sohail,

That is not an option at the moment.  I'll go an do my testing and draw conclusions after that.

Regards, Juan

[Former Member]

Hi Juan,

did you go for testing your setup? We have our DB and AS located in Europe and go for a big installation in JP with let's say 100-150 users. I wonder how the user experience will be if the AS is located in Asia.

Current latency profile from Japan is like GUI--- 260ms -->AS-- 10ms --> DB and would be then

GUI--- 80ms -->AS-- 260ms--> DB

I could imagine that VA0x, ME2xN etc would gain speed.

Looking forward to hear your results or opinion.

Gunter

[Former Member]

Hi Juan

Hope you must have finished your test project. Was your test successful and what is your conclusion.

is the performance better by keeping a separate App Server at the remote location.

Please let us know as we also would like to implement the same option of a remote application server.

Thnx

Tom.Jo

[Former Member]

Hi,

is it like

1 SystemA =ServerA (CI+DB) and ServerB(AS1) ?

Or

2. SystemA= ServerA(CI+DB) and SystemB=ServerB(CI+DB)  and you want to insert on ServerB a SystemA (AS1) and make connection with SystemB ?

[JPReyes]

Similar to 1.

Server A (CI+DB) in city A

Server B (AS) in city B

Regards, JP

[Former Member]

Do you mean one system with instances in different cities, or multiple systems?

If the first, I'd say that's a bad idea. All the DB traffic will have to travel over the WAN. That will surely hurt performance badly. Not that I've actually tried it

Steve.

[JPReyes]

Hi Steve,

One system with an instance on a a different location... The idea will be that all the interphases and GUI's and other devices will connect to the local instance rather than having individual connections traveling on the WAN..

More than the speed of the Link, I believe the latency will be essential.

The idea of the exercise will be gaining on performance. But I will like to know if there is someone that use this model and if this is a goer or not?

Regards, Juan

[Former Member]

Remember all the ABAP will run on the local instance, but it will be querying and updating a DB at the current central site. All the DB traffic will go over the WAN. Any large query will send a lot of data over that link. SAPgui uses a pretty lightweight protocol - I would expect you'd need to have a lot of local SAPgui connections concentrated through this remote instance before you'd get any payback.

As I said, this is only theory for me - I've never tried it. But I'm not convinced it makes any sense. I'll stop theorising now and let somebody with actual experience chime in!

Steve.

[JPReyes]

All valid points... we will have quite a few connection not only GUI's but also, devices connection to ICM and other third party talking to it.  This is why I want to check my options with the aim to obtaining the best performance either way. I'm expecting the DB intensive tasks will not be done through the remote application server (hopefully )

Regards, JP