Oracle ASM - yet another LVM (Instalation)

1. OS installation
For OS I will use CentOS with config:
- 1.5 GB RAM
- 20 GB harddisk for OS and software
- 6*8GB harddisks for ASM
I install only server cluster and exclude some packages like PCMCIA support, smartcard, power management, etc. They are not need for server.

1.1. After installation the first task is to update your system. For this I will use command
yum update yum* rpm* kernel*

At the moment I do not need more updates. After update the kernel its need to reboot server.

1.2. Install prerequisites packages. Here is the list of the packages:
xdpyinfo
libXmp
binutils
compat-libstdc++-33
elfutils-libelf
elfutils-libelf-devel
elfutils-libelf-devel-static
gcc
gcc-c++
glibc
glibc-common
glibc-devel
glibc-headers
kernel-headers
ksh
libaio
libaio-devel
libgcc libgomp
libstdc++
libstdc++-devel
make
sysstat
unixODBC
unixODBC-devel

Here and below the information is get directly from Oracle Technical Network, Documentation section.
First and second packages are not need according to the documentation, but my personal experience show me they are need.

2. Configure OS
2.1. Set kernel parameters
this is the list of parameters you should set in /etc/sysctl.conf to make software run. If some ot the parameters exist in original file just set recommended values
fs.aio-max-nr = 1048576
fs.file-max = 6815744
kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
net.ipv4.ip_local_port_range = 9000 65500
net.core.rmem_default = 262144
net.core.rmem_max = 4194304
net.core.wmem_default = 262144
net.core.wmem_max = 1048586

Do not forget to execute sysctl -p or reboot the server to get parameters set.

2.2. Add groups
oinstall, oper, dba, asmadmin, asmdba, asmoper

2.3. Create oracle user to have primary group oinstall and member of dba and oper and shell KornShell

2.4. Set in /etc/security/limits.conf number of files and number of processes for oracle user as follow
oracle              soft    nproc   2047
oracle              hard    nproc   16384
oracle              soft    nofile  1024
oracle              hard    nofile  65536

2.5. Add in /etc/profile the settings for ulimits for oracle user
if [ $USER = "oracle" ]; then
        if [ $SHELL = "/bin/ksh" ]; then
              ulimit -u 16384
              ulimit -n 65536
        else
              ulimit -u 16384 -n 65536
        fi
umask 022
fi

On my CentOS option, provided by Oracle documentation (ulimit -p 16384) because of version of ksh, so if you are with RHEL 5.x and if the version of ksh is like ksh-20080202-14.
_4.2 use ulimit -u 16384

3. Install Oracle ASM libraries and kernel modules. The packages should be downloaded from https://www.oracle.com/technetwork/database/enterprise-edition/downloads/oracle18c-linux-180000-5022980.html

Search for "Oracle Database XXX Grid Infrastructure"

Do not forget you should download and install libraries for your distribution and version of kernel. You can use this command to check the version of kernel
[root@rh-asm-ora rpm]# uname -r
2.6.18-164.15.1.