Dataguard and AIX-Largepages Problem

Recently we experienced serious problems after a dataguard failover where AIX-Largepages were in place. 

Luckily the failover was successfully completed, but the former primary database will be stopped by Dataguard-Broker. Stopped means killed in this case, but not only killed - instead the broker kills the instance and starts it immediately.

Fast is in this case too fast!

After killing the instance, the AIX-Largepages are not all released by the operating system. This needs a couple of seconds (or maybe milliseconds). 

There is no pause between terminating and starting the instance. As result the AIX-Largepages are not all released. Then we had a situation where the database had foo few Largepages and only possible workaround was to reboot the LPAR.

Oracle-Support says that there is no chance to configure kind of delay between termination and start of the instance.


Anyone else with an idea or solution?

Perhaps we could fix this while writing a wrapper for sqlplus, but this will be never a good idea in production and will definitely cause some other troubles...




SLES - autoyast installation with OVM

Following Oracles Documentation SLES should be supported by Oracle VM, but i didnt found SLES as Option while installing a new virtual server. During our project of moving to Oracle-VM, we wanted to use autoyast-installation of SLES. Our approach was to keep it as simple as possible to create new virtual machines. Cloning with OVM was not a real option, our Linux-Guys tend to prefer new installations rather than cloning. In OVM-Guest Boot-Order-Menue - this is what you get and what you can configure. Everything is clear? Nothing is clear, even the official documentation has not made us very happy with OVM.Voila_Capture 2015-11-19_09-44-29_vormWe want to add some more details here, because our SLES-Installations are performed with autoyast. And here is how we solved it: In Network-Boot-Path, you can type what ever you want, we have to modify the vm.cfg-File manually. Here is a sample file: 

vif = ['mac=00:xx:xx:xx:xx:xx,bridge=103ff836f1']
 OVM_simple_name = 'XXXXX'
 bootargs = ''
 uuid = '0004fb00-0006-0000-e2a0-b2a0266f7767'
 on_reboot = 'restart'
 cpu_weight = 27500
 memory = 8192
 cpu_cap = 0
 maxvcpus = 2
 OVM_high_availability = True
 OVM_os_type = 'Oracle Linux 7'
 OVM_domain_type = 'xen_pvm'

(some not important output removed here) In this file you can customize those 2 lines to install SLES with autoyast: 

bootargs='http://<server.domain>/<path_to_sles11sp4>/ install=http://<server.domain>/<path_to_sles11sp4>/' 
extra="install=http://<server.domain>/<path_to_sles11sp4>/ autoyast=http://<server.domain>/<path_to_sles11sp4/<autoyastfile.xml"

After modifying the vm.cfg directly, Start the VM - SuSE will come up magically! 
After successfull installation, it is required to stop the VM, to click something in
VM-Configuration and then saving the configuration. Please notice that every change in the
OVM-Webgui will delete the entrys from vm.cfg and will replace it with the default values.