Fault tolerance For SCS on ECC 6.0!!!

[Former Member]

Hello Friends,

We are planning to use FT (Fault tolerance) feature of VMware vSphere
5.0 for SAP SCS instance for ECC 6.0 system.

But we don’t have the option for that in sapinst for our version.

As you know, Currently VMware FT supports only one virtual CPU,

How about restricting end users using CI (keeping minumum work processes on CI) through SAP

logon load balkancing and using multiple dialog instances?

Would this configuration be suffice for 300-350 concurrent users?

Can you please share your experience on this?

Thanks,

Vishal

[Former Member · Accepted solution]

Hello,

I'd recommend reading this SAP Note:

Note 1678705 - Installation scenarios for a standalone ASCS instance

If your NetWeaver version isn't able to install a standalone ASCS, you can of course do as you already proposed: install the Primary Application Server (PAS) in a 1 vCPU VM and enable FT on that VM. You should just make sure that this PAS runs no batch jobs and that no user can logon to it, otherwise you would run into performance problems.

Kind regards,

Matthias

[Former Member · Accepted solution]

Thanks Matthias!!!

I've already gone through that note, but it is not for our SAP version : (

What in case, if we decide to disable the FT feature in the live Prod system and increse RAM and CPUs.

How much downtime and effort ( on Vmware part) will it  cause?

Regards,

Vishal

[Former Member · Accepted solution]

Hi Vishal,

you can disable FT and increase RAM and CPU with very low effort on VMware side (shutdown of the VM, reconfigure via vSphere Client, restart VM), but you might have to reconfigure OS and SAP profile as well. Be aware that you are losing the zero-downtime-protection in case of a hardware outage when you disable FT.

There are consulting companies which offer you installing a standalone ASCS even when sapinst doesn't provide this as an installation option.

If you don't want to undertake this effort, take a look at other HA concepts for SAP on VMware: https://www.box.net/shared/dfc7fcac9c0a9df34420

Kind regards,

Matthias

[michael_ruth3]

Hi,

You get your fault tolerance feature from VMware. But also look at SAP notes 1374671, and 1056052, may be of some help.

300-350 users on one CI with multiple instances might be fine but other factors come into play, such as how much data, how much disk space, etc.

Cheers