Strange Oracle Problems: Oracle database won't start

One of the desktops in my office is being used as a Server. It has Quad-core AMD Phenom X4, and 4 hard drives in Linux Software RAID 5 Configuration (Ok, it is a strange beast, because I was the one who chose the components and bought the system). We installed Centos 4.7 (64-bit), Oracle 10g, and SAP Netweaver. It is very much a hassle to set up, the 64-bit Oracle. But recently a strange error pops up when starting the Oracle database. It says, the shared_pool_reserved_size is out-of-bound (too large). The current setting is about 100 MB. At first, I wonders is this related to problems occured before, because the mixups between 64-bit and 32-bit parts of the Oracle RDBMS. I thought, the valid range of shared_pool_reserved_size is determined by the architecture (that is-64 or 32 bit).
Then, after some readings and pondering, I found out that not the shared_pool_reserved_size that was incorrect, it was the shared_pool. And it has nothing to do with the 64-bit architecture. Current setting of shared_pool is at 157MB, and shared_pool_reserved_size is only allowed from min_reserved_size to 0.5*shared_pool. The correct shared_pool setting is 1570MB (1.5 GB), and some mishaps make one of the numbers truncated..
Learnt some new Oracle commands while fixing this issue.. these could be run even when the database is idle (not mounted, not started).
/home/oraac1>sqlplus /nolog
>CONNECT / AS SYSDBA;
>CREATE PFILE FROM SPFILE;
This command creates a text-based parameter file from the existing binary parameter file. Which file? The default one. This would differ between systems, but I bet the default one is the one thats being used to start the Oracle RDBMS in normal conditions. In my windows Oracle XE, this is C:\oraclexe\app\oracle\product\10.2.0\server\dbs\SPFILEXE.ORA. In the Linux Oracle, this is /oracle/AC1/102_64/dbs/spfileAC1.ora, and the created text-based parameter file would be /oracle/AC1/102_64/dbs/initAC1.ora.
After the text-based PFILE was created, I just correct the shared_pool line (add another 0 in the end). Then..
>CREATE SPFILE FROM PFILE;
This command creates a binary startup parameter file from the existing text parameter file. Similar to the previous one, this also refers to default parameter files.
ok.. that done, I just need to start the whole SAP-Oracle system using startsap, and all is well.

Comments

Post a Comment

Popular posts from this blog

Long running process in Linux using PHP

Background To do stuff, I usually create web-based applications written in PHP. Sometimes we need to run something that takes a long time, far longer than the 10 second psychological limit for web pages. A bit of googling in stack overflow found us this  http://stackoverflow.com/questions/2212635/best-way-to-manage-long-running-php-script , but I will tell the similar story with a different solution. One of the long running tasks that need to be run is a Pentaho data integration transformation. Difficulties in long running PHP scripts I encountered some problems when trying to make PHP do long running tasks : PHP script timeout. This could be solved by running set_time_limit(0); before the long running tasks. Memory leaks. The framework I normally use have a bit of memory issues, this can be solved either by patching the framework (ok, it is a bit difficult to do, but I did something similar in the past ) or splitting the data to process into several batches. And if you
Read more

Reverse Engineering Reptile Kernel module to Extract Authentication code

Image
 This time I will show how to (partially) reverse engineer a linux kernel module. The linux kernel module is larger than usual kernel module because it is actually a Reptile-based rootkit dropped by some hacker.  Part 1. Get basic module information First we gather basic module info by using modinfo : [root@lb lkrg-0.9.1]# modinfo falc0n filename:       /lib/modules/3.10.0-1127.10.1.el7.x86_64/kernel/sdc/falc0n.ko intree:         Y license:         GPL retpoline:       Y rhelversion:     7.8 srcversion:     81F508029A53F7490CCDB44 depends:         vermagic:       3.10.0-1127.10.1.el7.x86_64 SMP mod_unload modversions   We could also refer to the kernel module file not yet installed in the OS : [root@lb lkrg-0.9.1]# file falc0n.ko falc0n.ko: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), BuildID[sha1]=1bde6abf4732eb620983032a47fbcf07689ece11, not stripped [root@lb lkrg-0.9.1]# modinfo falc0n.ko filename:       /root/lkrg-0.9.1/falc0n.ko intree:         Y license:         GPL retp
Read more

SAP System Copy Lessons Learned

Image
Background Earlier this year I was part of a team that does System Copy for a 20 terabyte plus SAP ERP RM-CA System. And just now I am involved in doing two system copy in just over one week, for much lesser amount of data. I think I would note some lessons learned from the experience in this blog. For the record, we are migrating from HP/UX and AIX to Linux x86 platform. Things that go wrong First, following the System Copy guide carefully is quite a lot of work - mainly because some important stuff are hidden in references in the guide. And reading a SAP note that are referenced in another SAP note, that are referenced in Installation Guide.. is a bit too much. Let me describe what thing goes wrong. VM Time drift The Oracle RAC Cluster have time drift problem, killing one instance when the other is shutting down. The cure for our VMWare-based Linux database server is hidden in SAP Note 989963 "Linux VMWARE Timing", which is basically add a tinker panic 0 in the
Read more