Skip to main content

10gR2 RAC on RHEL5.1 (x86_64)

Just a few issues you should be aware of when trying to install 10gR2 RAC on RHEL 5.1:

See Metalink 465001.1 for raw device configuration for RHEL 5. It's not explicitly said, but all disks used must be partitioned! Otherwise, if you don't partition the OCR disk, the from clusterware installation will fail (fail with “Failed to upgrade Oracle Cluster Registry configuration” error, with “Failed to call clsssinit” in log.)
The ASMLib will also refuse to stamp whole disk, a partition is required.

For OS configuration, see Metalink 421308.1. However, the sysctl parameters listed there do not exist on RHEL 5.1, you will have to use:

kernel.shmmni = 4096

kernel.sem = 250 32000 100 128

fs.file-max = 65536

net.ipv4.ip_local_port_range = 1024 65000

net.core.rmem_default = 262144

net.core.rmem_max = 262144

net.core.wmem_default = 262144

net.core.wmem_max = 262144

net.ipv4.tcp_rmem = 4194304 4194304 4194304
net.ipv4.tcp_wmem = 262144 262144 262144

You will also need to install one more rpm package (kernel-headers from CD1), but this will indicate the rpm command anyway.

As for network, remember that the localhost entries must be at the end of hosts file, so OUI will resolve current server with its name, instead of "localhost". (You would see this in the "Specify cluster configuration" screen.) If the node is listed as "localHost" (note the capital H), check your /etc/hosts for errors and that you can ping all the nodes listed (check also for typing errors).

Before running the script, read Metalink 414163.1. You will have to edit vipca and srvctl scripts (remove LD_ASSUME_KERNEL setting) and manually configure public/interconnect interfaces, finally running vipca interactively from root X session.
If you ran without these changes, remove the /etc/oracle/ocr.loc, remove the entries from /etc/inittab and run telinit so the can configure the OCR from scratch again.

Hope this helps:-)


Popular posts from this blog

ORA-27048: skgfifi: file header information is invalid

I was asked to analyze a situation, when an attempt to recover a 11g (standby) database resulted in bunch of "ORA-27048: skgfifi: file header information is invalid" errors.

I tried to reproduce the error on my test system, using different versions (EE, SE,,, but to no avail. Fortunately, I finally got to the failing system:

SQL> recover standby database;
ORA-00279: change 9614132 generated at 11/27/2009 17:59:06 needed for thread 1
ORA-00289: suggestion :
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-27048: skgfifi: file header information is invalid
ORA-00280: change 9614132 for thread 1 is in sequence #208

Interestingly, nothing interesting is written to alert.log n…

Reading data from PGA and SGA

Overview For our investigation of execution plan as it is stored in memory, we need in the first place to be able to read the memory.

We have the options of
x$ksmmem, reading SGA using SQL. Personally I don't like it, it's cumbersome and SGA read: obviously reading SGA only; it's fast and easy to doread process memory: can read PGA, process stack - and since the processes do map the SGA, too, you can read it as well. Unfortunately ptrace sends signals to the processes and the process is paused when reading it, but so far all my reads were short and fast and the processes did not notice. Some OS configurations can prevent you from using ptrace (e.g. docker by default), google for CAP_SYS_PTRACE.gdb: using your favorite debugger, you can read memory as well. Useful when investigating. Direct SGA read I always considered direct SGA read of some dark magic, but the fundamentals are actually very easy. It still looks like sorcery when actually reading the Oracle in…

Filter and access predicates

More than just column projections When we look around for further pointers in the tree nodes, we find more pieces resembling the column projections we have seen so far. With some experimenting, we will find out that these are access predicates and filters.

First of all, the location of these pointers is not always the same, it seems that the value at 0x34 is some kind of flag, indicating whether filters and/or access predicates are present, and where. Or whether there is just one, or more of them.  It probably also indicates what other info is present, but I have no idea what info that would be or what each value means.
Resembling, but different The data we see as predicates are not columns; after all, a predicate is a condition, not a single column. But the structure is similar to what we have seen with columns, and if we follow pointers further, we eventually build a tree, and some of the leaves are indeed just column projections.
After some contemplation, we realize it's all t…