1. Check the hardware parameters

• Check the processor details
  >cat /proc/cpuinfo
• Check the OS details
  >cat /etc/issue
• Check the Kernel version
  >rpm -qa | grep kernel
• Check the memory and the swap configuration details
  > free
• Check the disk space usage and the free space availability
  > df

2. Check and alter Kernel Parameters

• Check and alter the current setting of semaphores
  > cat /proc/sys/kernel/sem
  250 32000 100 100
  The order and the minimum values of the semaphore variables are semmsl 250, semmns 32000, semopm 100, and semni100
  > echo 256 32000 100 100 > /proc/sys/kernel/sem
  alter semmsl's value to 256
• Check the current settings for shared memory parameters
  >cat /proc/sys/kernel/shmmax
  >cat /proc/sys/kernel/shmmni
  >cat /proc/sys/kernel/shmall
  Also use echo command to alter their values.
• Set the maximum file-handles for a process to 131072. This value can be set by the command echo or ulimit.
  > cat /proc/sys/fs/file-max
  > echo 131072 > /proc/sys/fs/file-max
  or
  >ulimit -n 131072
• Open the port range between 1024 and 65000 for access.
  > cat /proc/sys/net/ipv4/ip_local_port_range
  > echo 1024 65000 > /proc/sys/net/ipv4/ip_local_port_range
• Set the maximum number of processes spawned by a user to 16348.
  > ulimit -u 16348
• The kernel parameter values are set temporarily, and they disappear on rebooting the system. Now set them permanent
  > cat /etc/sysctl.conf (editing this file)
  > sysctl -p (as root, to make new values effective)

3. Environment variables

• Check TMP variable
  Should set this variable to point to a directory having at least 1GB of free space, and also ensure that the installer has write privileges to this variable.
• If running the installer remotely, You should set the DISPLAY variable to the system name or the IP address of your locale workstation.
  > echo $DISPLAY
  :0.0
  > DISPLAY=123.45.67.89:0.0;export DISPLAY
• Empty the values for variables $ORACLE_HOME and $ORACLE_SID

4. HOSTS file

• Make sure that the format in the /etc/hosts file begins with the IP address followed by the domain-qualified host name and finally the aliases.
  > cat /etc/hosts
  127.0.0.1      localhost.localdoman       localhost

5. Default Port

• The database installed with OracleAS Infrastructure uses the port 1521 by default for Oracle Net Listener.
  > cat portlist.ini
  If 1521 is in use, you can use the staticports.ini file to assign the ports for OracleAS Infrastructure.
  > vi staticports.ini