Correlation between Kernel in /sapmnt/<SID>/exe ans /usr/sap/<SID>/DV../exe

[Private_Member_107037]

Hello,

we are working with linux systems abap stack.

Obviously the kernel is copied copied from /sapmnt/ exe are used during runtime?

Is there any idea out ther?

Thank you a lot!

Jens

[Former Member]

Jens,

Can you clarify what you mean by?

"Obviously the kernel is copied copied from /sapmnt/<SID>/exe to

/usr/sap/<SID>/DV..xy../exe during startup. "

[Private_Member_107037]

Hello,

what I understood as a change with sap Netweaver 6.40 or 6.20, is that:

When you execute "startsap" on unix level;

The subroutine 'sapcpe' (one of the first in Startprofile) is copying your executables from the global directory /sapmnt/<SID>/exe/ to the instance directory: /usr/sap/<SID>/DV..<instancenr>/exe.

The instance is running with the executables in the instancedirectory.

My idea to reduce downtime was: Upgrade the global directory, coordinate a downtime and simply restart. Doing everything else (saving old kernel, copying new kernel) during the uptime of the system.

Unfortunally things did not work the way i thought. and now i would like toi know where is my mistake? I guess that some parts of the global directory are used even when the executables run in the instance directory. But i'm not sure.

Thank You, if you have an idea.

sincerely Jens

[Former Member]

Hi,

Do you not have a centrally mounted /sapmnt/SID on your application servers? sapcpe works for distributed instances (see http://help.sap.com/saphelp_nw04/helpdata/en/1f/8312264bc511d189750000e8322d00/content.htm). Do you actually have an exe directory in /usr/sap/SID/DB../? Are you refering to stand alone java stack (See this /people/community.user/blog/2006/12/04/use-sapcpe-for-kernel-update-on-netweaver-2004-as-java)?

Any way for abap stack, if you goal is to minimize the downtime, you can just copy (cp -rp) your /sapmnt/SID/exe directory to /sapmnt/SID/exe_new and extract the new kernel files in exe_new directory. When you have down time you just need to rename exe to exe_old and exe_new to exe and run saproot.sh.

-RK

Edited by: RK on Apr 17, 2008 7:11 AM

Edited by: RK on Apr 17, 2008 7:14 AM

[Private_Member_107037]

Hello RK,

thanks a lot the HELP SAP Link on sapcpe helps.

But honestly the situation is not described correctly on the HELP SAP.

Yes we do have a central instance. We do have the 'centrally' mounted filesystem /sapmnt/<SID>/exe. And of course we do have the Link-structure from /usr/sap/<SID>/SYS/exe to the centrally filesystem. The /usr/sap/<SID>/SYS/exe is called locally in the SAP Help which is not true. SYS stands for the whole system, so its basically a central directory with central joblog, etc. ..

So far so good. But what sapcpe ist really doing, is that it is copying excutables to the in fact locally l directory /usr/sap/<SID>/DV*/exe.

The SAP Help writes: "By default, sapcpe uses soft links to make other, less frequently-used executables available" I can't find any softlinks in /usr/sap/<SID>/DV*/exe.

In /sapmnt/<SID>/exe there are a 197 files in /usr/sap/<SID>/DV/exe there are 160 files, that is as described in the SAP Help. So I guess that the most important executables during runtime are taken from /usr/sap/<SID>/DV/exe and some libraries are simply still taken from /sapmnt/<SID>/exe

But you are right about your proposal of minimizing downtime. I will follow it next time.

Thank you!

Jens