Sunday, July 23, 2017

Deploying Oracle RAC Database 12c Lab on Red Hat Enterprise Linux 7 with Virtual Box -racattack Repack


Introduction:

This document provides a step-by-step deployment procedure with some of best practices to install and configure an Oracle Real Application Clusters (RAC) Database 12c Release 1 (12.1)* with Oracle ASM on Linux RedHat Entreprise 7 virtual machines (Virtualbox). Most of it is inspired by the RACAttack project  that was written collaboratively by many authors all around the world (Seth Miller, Yury Velikanov, Ludovico Caldara and Björn Rost...to name a few) . 

If you want to learn more or contribute to the project please visit their official Wiki Page.
In addition I have inserted some relevent guidelines regarding Oracle 12c on RHEL 7 from RedHat’s website (Deploying Oracle RAC Database 12c on Red Hat Enterprise Linux 7 - Best Practices)

Implementation process: 
We will focus on the following tasks:
Main steps
   1. Setup VirtualBOX
   2. Create the first node
   3. Create shared ASM devices
         -   Configuring Device Mapper Multipathing
         -   Using udev Rules instead of Oracle ASMLib
   4. Clone node
   5. Install Grid Infrastructure 12c Release 1
   6. Install Database Software 12c Release 1
   7. Create Database
   8. Enjoy and experiment
Lab environment requirement & overview
Host requirement:

a. Hardware:

RAM : min 8 GB - actual 10 GB
DISK: min 50 GB - actual 500 GB 
Internet connection

b.
Software:

Host:  OS - Windows /Linux                Hypervisor -  virtualBox    Other tools needed: Putty, Vnc Viewer
* RedHat free Evaluation Subscription can be done by creating an account with a business email address  (here).
image

Oracle software -  
1- Login to: http://edelivery.oracle.com/ with your Oracle Account
2- On the Media Pack Search page, select:
       Product pack: Oracle Database      Platform: Linux x86-64
3- Click GO then Select and download the following products :


  Grid Infrastructure 12c Release 1 (12.1.0.2.0) and Oracle Database 12c Release 1 (12.1.0.2.0)
image

               
c. Space requirements

   Disk space consumed for Oracle Grid Infrastructure Home and Oracle Database Home Enterprise Edition may vary.

Software                                                                                                             Disk Space           
Oracle Grid Infrastructure Home (includessoftware files)                                                                        12 GB
Oracle Database Home Enterprise Edition(includes software files and data files)                                       12 GB
/tmp                                                                                                                                                                 1 GB

Swap Space (Recommended) :

RAM                                                                                                                    Swap space           
2Gb to 16Gb                                                                                                                            Equal to the size of RAM         
          > 16Gb                                                                                                                                16 GB of RAM 

Filesystem layout to properly install the Oracle Grid Infrastructure and Oracle Database software
Filesystem                                size     Used      Avail      Use%      Mounted on
/dev/mapper/rhel-root                  27G      15G       13G        54%               /
devtmpfs                                     1.6G         0        1.6G          0%              /dev
tmpfs                                           3.0G         0        3.0G          0%             /dev/shm
tmpfs                                            1.6G                   8.4M         1%            /run
tmpfs                                            1.6G        0         1.6G         0%            /sys/fs/cgroup
tmpfs                                            1.6G    121M     377M       25%           /boot



1. Setup VirtualBOX                                                                              Go to Top

    a. Network configuration :   I have used the following network setup. Feel free to adjust to your needs:
     - Hostnames  london1,london2                 Domaine: Evilcorp.com  ( Mr Robot fan here…)   

   Public IPs 192.168.78.0/24  (51,52)

    Interconnect 172.16.100.0/24   (51,52) 
           o Private IPs available from RAC nodes only


     - SCAN
           o Name => london-cluster-scan.evilcorp.com
           o IPs  => 192.168.78.251/252/253

     b. Preparation:
     1. From the main VBOX screen, choose File > Preferences > Network.
     2. Double click on VirtualBox Host-Only Ethernet Adapter. Update the settings as shown and click Ok twice.
        IPv4 Address: 192.168.78.1
        IPv4 Network Mask: 255.255.255.0
     3. Create a virtual hard drive now >
                               VDI (VirtualBox Disk Image)> Dynamically allocated> Location /London> size 30G
     4. Disable USB
     5. Allocate the minimum physical memory required ( 3.5G<Memory<4G )
      o Storage: Delete the Empty disk under the IDE Controller
                        > Add CD/DVD Device
                        > Locate and open the rhel-server-7.1-x86_64- dvd.iso file.

     o Network:  Adapter 1: Host-only Adapter.  
                        Adapter 2: Internal Network  (Name: rac-priv) .    
                        Adapter 3: NAT .

VirtualBox_Settings_Network_Adapter_1 VirtualBox_New_VM_Settings_Network_Adapter_2VirtualBox_New_VM_Settings_Network_Adapter_3

   Shared folder 12gR2  : on shared folder link the diretory containing all the installation files and name it 12gR2
   You can mount it later using the following command   mount -t vboxsf 12gr2 /mnt

2. Create the first node                                                                            Go to Top

1). Linux RedHat Enterprise installation :
  A. Click on Start to boot the virtual machine. If asked to select a start-up disk, choose RHEL7 iso.                
       o Skip the CD testing by pressing the right arrow key and press enter.
       o From now on you can use the mouse to navigate. To unlock the mouse and keyboard from the VM, hit the right Ctrl or
           Alt key.
          Click Next.



  B. Under LOCALIZATION 
       o LANGUAGE SUPPORT : Leave/select English (English) selected .
         -  Adapt or leave the timezone settings as they are and exit.
       o KEYBOARD : Leave U.S. English selected and exit (unless you have another preferred keyboard layout).



  C. Under INSTALLATION DESTINATION Leave Basic Storage Devices selected and exit.
      o Click Yes, discard any data for the warning box stating The storage device below may contain data.

  D. Under NETWORK AND HOSTNAME  
     In the hostname field, type london1.evilcorp.com .

   D.1 Highlight EnpOs3 interface and click the Configure... button.
  • Click the IPv4 Settings tab. 


  • Click the Connect automatically checkbox.
  • Click the Method: dropdown and select Manual.
  • Click Add and type 192.168.78.51 for the address.
  • Leave Netmask at 24.
  • In the DNS servers: box, type 192.168.78.51, 192.168.78.52.
  • In the Search domains: box, evilcorp.com then Click the Save .

  •    D.2 Highlight EnpOs8 Interface and click the Configure... button.

  • Click the IPv4 Settings tab.
  • Click the Connect automatically checkbox.
  • Click the Method: dropdown and select Manual.
  • Click Add and type 172.16.100.51.
  • Change Netmask to 24.
  • Click the Save button. 

  •    D.3 Highlight EnpOs9 Interface and click the Configure... button.
    • Click the IPv4 Settings tab.
  • Click the Connect automatically checkbox.
  • Click the Method: dropdown and select Automatic (DHCP) addresses only.
  • Click the Save button.
  • Click Close to close the NETWORK & HOST NAME menu and click Next.
  •   E. Under SOFTWARE SELECTION
          o  Choose infrastructure Server: Select  DNS Name Server and Compatibility Libraries Add-Ons then exit.



       F. Complete the Installation
         o  Enter the Root Password as racattack  (Click Use Anyway when warned about the weak password).
         o  Click Begin Installation
         o  When Installation is complete,Click Reboot.



    2). Linux post installation configuration:

    - We will first have to change the network interface naming from EnpOs3/8/9 to Eth0/1/2 through this *** Tutorial>>.

    To connect to the new virtual machine, create a connection in Putty Called london1 with the IP Address of 192.168.78.51. Optionally, create another connection for london2 with the IP Address of 192.168.78.52 that will be created later as a clone of london1.




       Open the london1 connection by clicking Open.
         - Enter root at the login as: prompt and racattack at the password: prompt.
         - Remove special character occuring when hitting backspace on the terminal


    # stty erase ^?    or CTRL+H
           
        o Verify the network configuration via network manager user interface

    [root@localhost]# nmtui
        
         o In case the hostname wasn't set durring the installation run the following

    [root@localhost]# hostnamectl set-hostname london1.evilcorp.com

        o Confirm host configuration

    [root@london1]# hostnamectl status
      Static hostname: london1
      Icon name: computer               Chassis: n/a
      Machine ID: dbd60b83d0d9470cbbf07397a6ab261e
      Boot ID: 85bde258cf7b49458a397db3a7ae36a1
    Virtualization: kvm
      Operating System: Red Hat Enterprise Linux Server 7.1 (Maipo)
           CPE OS Name: cpe:/o:redhat:enterprise_linux:7.1:GA:server
                         Kernel: Linux 3.10.0-229.el7.x86_64
                   Architecture: x86_64

    - Shared memory allocation
        *New in REDHAT 7:  tmpfs is a file system that keeps all files and folders in the virtual memory of the operating system. 
    Here are some of the known purposes of tmpfs:

    Filesystem         Purpose
    /dev                     contains the special device files for all the devices.
    /dev/shm             contains shared memory allocation
    /run                      used for system logs
    /sys/fs/cgroup      used for cgroups, a kernel feature to limit, police and account the resource usage of certain processes
        
          o Resize swap and dev/shm to 2G (shared memory allocation):


    [root@london1]# dd if=/dev/zero of=/swapfile bs=1024k count=2000   ---OR fallocate -l 2G /swapfile              
    1-
    Setup the swapfile                                                                                                                                    
    [root@london1]#
     mkswap /swapfile 
    2- It is recommended that the permissions are changed to prevent the swap being world readable.           
    [root@london1]# chmod 0600 /swapfile
    3- To enable the swap file immediately but not at boot time                                                                                                    [root@london1]#  swapon /swapfile  

         o Setting & Mounting Shared Memory File System on Linux (I actually assigned 3G )

    [root@london1]#  mount -t tmpfs shmfs -o size=3072m /dev/shm

         o To enable it at boot time, edit /etc/fstab to include the following entry:

    [root@london1]# vi /etc/fstab  (replace default by size clause)
    [..]
    tmpfs                   /dev/shm                tmpfs   size=3g        0 0
    /swapfile                  swap                swap    defaults        0 0

          o Check the new swap size

    [root@london1]#  swapon -s                                        ---- OR # cat /proc/swaps

    - OS Configuration
    Install Required Linux Packages for Oracle Grid Infrastructure and Oracle Database 12.1.0.2 :

    Required Packages
    ------------------------------------------------------------
    binutils
    libX11
    compat-libcap1
    libXau
    compat-libstdc++-33
    libaio
    gcc
    libaio-devel
    gcc-c++
    libdmx
    glibc-devel
    glibc
    ksh
    make
    libgcc
    sysstat
    libstdc++
    xorg-x11-utils
    libstdc++-devel
    xorg-x11-xauth
    libXext
    libXv
    libXtst
    libXi
    libxcb
    libXt
    libXmu
    libXxf86misc
    libXxf86dga
    LibXxf86vm
    nfs-utils

        o Add a local DVD repository

    [root@london1]# mount /dev/cdrom /media
    [root@london1]# vi  /etc/yum.repos.d/rhel71.repo
    [rhe64]
    name=Red hat Linux 7.1 x86_64
    baseurl=file:///media
    gpgcheck=0
    enabled=1

       Add Virtual Box guest addition plugin
    - Note:
    Due to some headers mismatch check and possible execution errors, few rpms may need to be installed first  :

    [root@london1]# yum install gcc gcc-c++ kernel-devel autoconf automake -y
    [root@london1]# umount /media

    - Make the VirtualBox guest additions available to the OS by clicking Devices>Install Guest Additions
           o Run the below commands

    [root@london1]# mount /dev/cdrom /media
    [root@london1]# sh /media/VBoxLinuxAdditions.run
    [root@london1]# umount /media


    Note : Some of the Install Guide requirements will already be present from the "default-RPMs" foundation of Linux that you started with (including gcc’s  installed above) . The rest is located in the DVD except the compat_libstdc++-33.
    - compat-libstdc++-33-3.2.3-72.el7.x86_64 needs to be downloaded from redhat repository (30 days trial) or can be found as Oracle linux equivalent on https://yum.oracle.com/repo/OracleLinux/OL7  or rpm.pbone.net
    - Make the linux RHEL7 DVD available to the OS
    - Run the below commands to install the required rpms

    [root@london1]# mount /dev/cdrom /media
    [root@london1]#   yum install binutils compat-libcap1 compat-libstdc++-33 elfutils-libelf elfutils-libelf-devel gcc gcc-++ glibc glibc-common glibc-devel glibc-headers ksh libaio libaio-devel libgcc libstdc++ libstdc++-devel make numactl-devel sysstat unixODBC unixODBC-devel libXxf86vm  cpp libdmx mpfr kernel-headers xorg-x11-utils libXmu xorg-x11-xauth libXt libXv libXxf86dga nfs-utils                                                                                                        
    [root@london1]#   rpm -ivh compat-libstdc++-33-3.2.3-72.el7.x86_64

        o Additional rpms for other tools (i.e VNC)face    

    [root@london1]#  yum install tigervnc-server.x86_64 xclock man parted.x86_64 unzip.x86_64 xterm lsof bind xorg-x11-twm
    .. warning... No package xorg-x11-twm available

        o Note: The reason behind the non-availability of xorg-x11-twm package is because it has been discontinued in RHEL 7 and replaced by metacity. 
    Solution : Install the below packages :

    [root@london1]#  yum install xorg-x11-xinit xorg-x11-font-utils xorg-x11-fonts-Type1 libX11-common xorg-x11-xauth libX11 dbus-x11 xorg-x11-server-utils xorg-x11-xkb-utils tigervnc-server xterm

               o Next , just download and install xorg-x11-twm from your favorite CentOS 6 mirror 

    [root@london1]# rpm -ivh --nodeps xorg-x11-twm-1.0.3-5.1.el6.x86_64.rpm

             o  For maximum flexibility you can add the following CentOS 7 packages 

    [root@london1]#   yum install xorg-x11-fonts-75dpi xorg-x11-fonts-100dpi xorg-x11-fonts-misc
          
       o Finally, verify that all the rpms are installed by typing the below rpm commands

    --- Oracle RPMs
    [root@london1]# rpm -vq cloog-ppl libXxf86misc ppl binutils compat-libcap1 compat-libstdc++-33 elfutils-libelf elfutils-libelf-devel gcc gcc-c++ glibc glibc-common glibc-devel glibc-headers ksh libaio libaio-devel libgcc libstdc++ libstdc++-devel make numactl-devel sysstat unixODBC unixODBC-devel libXxf86vm  cpp libdmx mpfr kernel-headers xorg-x11-utils libXmu xorg-x11-xauth libXt libXv libXxf86dga  nfs-utils
    -- VNC rpms
    [root@london1]# rpm -vq xorg-x11-xinit xorg-x11-font-utils xorg-x11-fonts-Type1 libX11-common xorg-x11-xauth libX11 dbus-x11 xorg-x11-server-utils xorg-x11-xkb-utils tigervnc-server xterm

       o System parameter change :      Here is the list of system parameters to be adapted :
  • Virtual Memory:
  • Shared Memory (SHMMAX, SHMALL, SHMMNI)
  • Semaphores (SEMMSL, SEMMNI, SEMMNS)
  • Ephemeral Network Ports
  • Optimizing Network Settings
  • Setting NOZEROCONF
  • Increasing synchronous I/O Requests
  • Increasing File Handles
  • Kernel Panic On OOPS Parameter
  • Disabling the avahi­daemon service (N/A)

  •     Note: Prior to making any changes to the /etc/sysctl.conf, create a backup as follows:
    [root@london1]# cp /etc/sysctl.conf /etc/sysctl.conf.bkup 

        o Adapt the content of sysctl.conf with the bellow lines if they are different or not present.

    [root@london1]# cat /etc/sysctl.conf
    net.ipv4.ip_forward = 0
    net.ipv4.conf.default.rp_filter = 1
    net.ipv4.conf.default.accept_source_route = 0
    net.core.rmem_default = 262144
    net.core.rmem_max = 4194304
    net.core.wmem_default = 262144
    net.core.wmem_max = 1048576
    kernel.sysrq = 0
    kernel.core_uses_pid = 1
    net.ipv4.tcp_syncookies = 1
    net.bridge.bridge-nf-call-ip6tables = 0
    net.bridge.bridge-nf-call-iptables = 0
    net.bridge.bridge-nf-call-arptables = 0
    vm.swappiness = 0
    vm.dirty_background_ratio = 3
    vm.dirty_ratio = 80
    vm.dirty_expire_centisecs = 500
    vm.dirty_writeback_centisecs = 100
    kernel.msgmnb = 65536
    kernel.msgmax = 65536
    kernel.shmmax = 68719476736
    kernel.shmmni = 4096
    kernel.shmall = 4294967296
    kernel.sem = 250 32000 100 128
    fs.aio-max-nr = 1048576
    fs.file-max = 6815744
    net.ipv4.ip_local_port_range = 9000 65500
     

        o For the changes to take effect immediately, run the following command

    [root@london1]# sysctl -p /etc/sysctl.conf

        o Set NOZEROCONF on  /etc/sysconfig/network file
           Modify this line to ensures that the route 169.254.0.0/16 is not added to the routing table. If the file is empty skip this stepce
           NOZEROCONF=yes

        o Disable SElinux
    SELinux can prevent to establish a correct SSH communication between two hosts, or prevent the creation of ASM disks with the oracleasm tool.To disable SELinux, Edit the file /etc/selinux/config as follow:

    [root@london1]# vi /etc/selinux/config
    --- Line to modify —>…  
    SELINUX=disabled  

    --- Reboot the machine and confirm SELINUX is disabled
    [root@london1 ~]# getenforce 
    Disabled

         o Disable the avahi­daemon service if loaded:

    [root@london1]# systemctl stop avahi-dnsconfd                                                                                         
    [root@london1]# systemctl stop avahi-daemon
    [root@london1]# systemctl disable avahi-dnsconfd
    [root@london1]# systemctl disable avahi-daemon

        o Turn off and disable the Firewall:
    If the firewall option is operating, you will need to first manually disable UDP ICMP rejections
    *Note:   RHEL 7 introduced firewalld in replacement of iptables which makes /etc/sysconfig/iptables no longer relevant.

    [root@london1]# systemctl stop firewalld            --- RHEL6 /etc/rc.d/init.d/iptables stop
        
         o Turn UDP ICMP rejections off for all subsequent server reboots (which should always be turned off).

    [root@london1]# systemctl disable firewalld        --- RHEL6 chkconfig iptables off 
    [root@london1]# rm '/etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service'
    [root@london1]# rm '/etc/systemd/system/basic.target.wants/firewalld.service'
    [root@london1]# systemctl status firewalld
       
         o Add Users and groups

    [root@london1]# groupadd --gid 501 oinstall
    [root@london1]# groupadd --gid 502 dba
    [root@london1]# groupadd --gid 503 asmdba
    [root@london1]# groupadd --gid 504 asmoper
    [root@london1]# groupadd --gid 505 asmadmin
    [root@london1]# groupadd --gid 506 oper
           
    Note :
    vboxsf group allows access to the shared folders

    [root@london1]# useradd --uid 501 --gid oinstall --groups dba,oper,asmdba,asmoper,vboxsf -d /home/oracle -s /bin/bash -c "Oracle Software Owner" oracle
    [root@london1]#passwd oracle                                                                                                                              
    Type : racattack
    [root@london1]#useradd --uid 502 --gid oinstall --groups dba,asmadmin,asmdba,asmoper,vboxsf -d /home/grid -s /bin/bash -c "Grid Software Owner" grid
    [root@london1]#passwd grid
          Type : racattack
          
         o Setting Shell Limits for the Grid and Oracle Users

    [root@london1]# vi /etc/security/limits.d/99-grid-oracle-limits.conf                                                                                
    ## add following hard soft limits
    oracle soft nproc 2047
    oracle hard nproc 16384
    oracle soft nofile 1024
    oracle hard nofile 65536
    oracle soft stack 10240
    oracle hard stack 32768
    grid soft nproc 2047
    grid hard nproc 16384
    grid soft nofile 1024
    grid hard nofile 65536
    grid soft stack 10240
    grid hard stack 32768

    - Or :  Alternatively,you can update the resource limits in the /etc/security/limits.conf configuration file for the Oracle installation owner by adding the following lines.

    [root@london1]# vi  /etc/security/limits.conf                                        
    ##  oracle user limits add the following    
    oracle soft nproc 2047
    oracle hard nproc 16384
    oracle soft nofile 1024
    oracle hard nofile 65536
    oracle soft stack 10240
    oracle hard stack 32768

         o As the root, create a shell script labeled oracle-grid.sh within /etc/profile.d/ to create the appropriate ulimits 
           for the oracle and grid user .

    [root@london1]# vi /etc/profile.d/oracle-grid.sh
    # Setting the appropriate ulimits for oracle and grid user
    if [ $USER = "oracle" ]; then
    if [ $SHELL = "/bin/ksh" ]; then
    ulimit -u 16384
    ulimit -n 65536
    else
    ulimit -u 16384 -n 65536
    fi
    fi
    if [ $USER = "grid" ]; then
    if [ $SHELL = "/bin/ksh" ]; then
    ulimit -u 16384
    ulimit -n 65536
    else
    ulimit -u 16384 -n 65536
    fi
    fi
         
          o Add the following lines to the /etc/pam.d/login file to use limits, if it does not already exist.

    session    required     /lib64/security/pam_limits.so
    session    required     pam_limits.so
        
        *Note :
      If you want to reference /lib/security as default library directory create the folder and run the following

    [root@london1]#  ln -s /lib64/security/* /lib/security/ .
        
          o Add two modified .bash_profile to /home/oracle & /home/grid directories respectively
         
     “.bash_oracle_profile” and “.bash_grid_profile” 
            
    (rename each of them to 
    .bash_profile and assign a value to ORACLE_SID accordingly )

          o Enable ssh: Run as oracle /and grid
     

    [oracle/Grid@london1]#  ssh-keygen -t rsa                                                                                                                       >ENTER                                                                                                                                                                         >ENTER                                                                                                                                                                 >ENTER.                                                                                                                                                                       [oracle@london1]#  cat /home/oracle/.ssh/id_rsa.pub >>/home/oracle/.ssh/authorized_keys
    [grid@london1]#  cat /home/grid/.ssh/id_rsa.pub >>/home/grid/.ssh/authorized_keys
          
            o Create Grid oracle Directories
           o Create Oracle inventory Directory
     

    Create Oracle inventory Directory                                                                                                        
    [oracle/Grid@london1]#  mkdir -p /u01/app/OraIventory                                                                         
    [oracle/Grid@london1]# chown -R grid:oinstall /u01/app/OraIventory                                                          
    [root
    @london1]# chmod -R 775  /u01/app/OraIventory

    - Create Grid Infrastrcuture Home directory  and Oracle base  
                                                                                                             
    [
    root@london1]# mkdir –p  /u01/grid/oracle/product/12.1.0.2/grid
    [root@london1]# chown -R grid:oinstall  /u01/grid
    [root@london1]# chmod -R 775   /u01/grid
    [root@london1]# mkdir –p  /u01/app/grid               ----- Oracle BASE                                                                                   
    [root@london1]# chown -R grid:oinstall /u01/app/grid                                                                                                    [root@london1]# chmod -R 775 /u01/app/grid                                                                                                                 

    -
    Create database Oracle Base Directory                                                                                                                                     
    [root
    @london1]# mkdir -p  /u01/app/oracle                                                                                                                      [root@london1]# mkdir -p  /u01/app/oracle/cfgtoollogs                                                                                                    

    -
     Needed to ensure dbca will be able to launch after rdbms install                                                                              
    [root
    @london1]# chmod -R 775 /u01/app/oracle/cfgtoollogs/                                                                                              [root@london1]# chown -R oracle:oinstall /u01/app/oracle                                                                                              [root@london1]# chmod -R 775 /u01/app/oracle                                                                                                                                  

    -
    Create Oracle RDBMS Home directory                                                                                                                       
    [root@london1] # mkdir -p /u01/app/oracle/product/12.1.0.2/db_1                                                                                    [root@london1]# chown -R oracle:oinstall /u01/app/oracle/product/12.1.0.2/                                                                [root@london1]# chmod -R 775 /u01/app/oracle
          
          o Setup oracle root profiles
     
    [root@london1]# vi /etc/oratab                 grid:/u01/grid/oracle/product/12.1.0.2/grid:N                                                                                               
    [root@london1]# chown oracle:dba /etc/oratab
         
         o  Add  following lines to /root/.bashrc  

    ORAENV_ASK=NO                                                                                                                                                   ORACLE_SID=grid                                                                                                                                                           
    . oraenv >/dev/null                                                                                                                                                    
    unset ORAENV_ASK   

    3). RAC DNS configuration 

    --------------Create  Forward zone--------------                                                                                                                  
    [root@london1 ~]# touch /var/named/evilcorp.com
    [root@london1 ~]# chmod 664 /var/named/evilcorp.com
    [root@london1 ~]# chgrp named /var/named/evilcorp.com
    [root@london1 ~]# chmod g+w /var/named/evilcorp.com.rev
    --------------Create Reverse zone--------------
    [root@london1 ~]# touch /var/named/evilcorp.com.rev
    [root@london1 ~]# chmod 664 /var/named/evilcorp.com.rev
    [root@london1 ~]# chgrp named /var/named/evilcorp.com.rev
    [root@london1 ~]# chmod g+w /var/named/evilcorp.com.rev
    [root@london1 ~]# chmod g+w /var/named
    [root@london1 ~]# cp /etc/named.conf /etc/named.conf.org
          
          o  Edit named.conf : empty-zones-enable no; within options setion will allow one reverse zone for all networks

    --------------Configure  Forward zone--------------                                                                              
    [root@london1 ~]# sed -i -e 's/listen-on .*/listen-on port 53 { 192.168.78.51; };/' \-e 's/allow-query .*/allow-query { 192.168.78.0\/24; localhost; };\n allow-transfer { 192.168.78.0\/24; };/' \-e 's/session.key";/session.key"; \n empty-zones-enable no;\n/;' \-e '$azone "evilcorp.com" {\n type master;\n file "evilcorp.com";\n};\n\nzone "in-addr.arpa" {\n type master;\n file "evilcorp.com.rev";\n};' /etc/named.conf
          
          o  Edit forward zone (evilcorp.com)

    --------------Forward zone--------------                                                                                                                                    [root@london1 ~]# echo '$TTL 3H
    @            IN SOA london1 hostmaster (
    101 ; serial
    1D ; refresh
    1H ; retry
    1W ; expire
    3H ) ; minimum
                   NS  london1
                   NS  london2
    localhost     A   127.0.0.1
    london1       A   192.168.78.51
    london1-vip   A   192.168.78.61
    london1-priv  A   172.16.100.51
    london2       A   192.168.78.52
    london2-vip   A   192.168.78.62
    london2-priv  A   172.16.100.52
    london-cluster-scan A 192.168.78.251
    london-cluster-scan A 192.168.78.252
    london-cluster-scan A 192.168.78.253' >/var/named/evilcorp.com
         
            o Edit reverse Zone (evilcorp.com.rev)

    --------------Reverse zone--------------                                                                                                                                   [root@london1]#echo '$TTL 3H
    @           IN SOA london1.evilcorp.com. hostmaster.evilcorp.com(
    101 ; serial
    1D ; refresh
    1H ; retry
    1W ; expire
    3H ) ; minimum
                   NS  london1.evilcorp.com.
                   NS  london2.evilcorp.com.
    51.78.168.192 PTR london1.evilcorp.com.
    61.78.168.192 PTR london1-vip.evilcorp.com.
    51.100.16.172 PTR london1-priv.evilcorp.com.
    52.78.168.192 PTR london2.evilcorp.com.
    62.78.168.192 PTR london2-vip.evilcorp.com.
    52.100.16.172 PTR london2-priv.evilcorp.com.
    251.78.168.192 PTR london-cluster-scan.evilcorp.com.
    252.78.168.192 PTR london-cluster-scan.evilcorp.com.
    253.78.168.192 PTR london-cluster-scan.evilcorp.com.
    ' > /var/named/evilcorp.com.rev

        
          o Generate the rndc.key file.  alternative to writing the rndc.conf file ( automatic rndc configuration) 

    [root@london1]# rndc-confgen -a -r /dev/urandom[root@london1]# chgrp named /etc/rndc.key   
    [root@london1]# chmod g+r /etc/rndc.key                                

           o Restart named service and Enable at boot 

    [root@london1]#service named restart                                                                                                                                                 ---Redirecting to /bin/systemctl restart  named.service   
    [root@london1]# chkconfig named on                                                                          
     
    *Note:
    Forwarding requires to add named.service simlink to run  'systemctl enable named.service'.    

    [root@london1]# ln -s '/usr/lib/systemd/system/named.service' '/etc/systemd/system/multi-user.target.wants/named.service'                                 
         
            o Finally check  if the DNS configuration is well set      

    [root@london1]# vi /etc/sysconfig/network-scripts/ifcfg eth2                                                           
    --verify if parameter PEERDNS is set to no  to prevent the resolv.conf from being overwritten by the dhcp client:
    verify   zone   
                PEERDNS=no 
    [root@london1]# cat /etc/resolv.conf
    # Generated by NetworkManager                                                                                                                                              
    search            evilcorp.com                                                                                                                                                 nameserver     192.168.78.51                                                                                                                                             nameserver     192.168.78.52                             
    [root@london1]# named-checkzone evilcorp.com.rev  /var/named/evilcorp.com.rev                     
    // verify zone                          
    OK                                                                       
    [root@london1]# netstat -tulnp | grep –i 53
    tcp       0      0    192.168.78.51:53    0.0.0.0:*   LISTEN     491/named
    tcp       0      0    127.0.0.1:953       0.0.0.0:*   LISTEN     491/named                      udp       0      0    192.168.78.51:53    0.0.0.0:*              491/named
    [root@london1 ~]# host london1
    london1.evilcorp.com has address 192.168.78.51
       

    3. Create shared ASM devices                                                               Go to Top 
      Create and attach vm disks

        o Execute the following command to create 5 disks for ASM (+DATA diskgroup will use 3 ). Each command is in a        single line.

    C:>  "C:\Program Files\Oracle\VirtualBox\VBoxManage" createhd --filename "C:\VM\RAC lab\london1\asm1.vdi" --size 4096 --format VDI --variant Fixed                                                       
    C:>  "C:\Program Files\Oracle\VirtualBox\VBoxManage" createhd --filename "C:\VM\RAC lab\london1\asm2.vdi" --size 4096 --format VDI --variant Fixed                                                          
    C:> "C:\Program Files\Oracle\VirtualBox\VBoxManage" createhd --filename "C:\VM\RAC lab\london1\asm3.vdi" --size 4096 --format VDI --variant Fixed 
    C:> "C:\Program Files\Oracle\VirtualBox\VBoxManage" createhd --filename "C:\VM\RAC lab\london1\asm4.vdi" --size 4096 --format VDI --variant Fixed
    C:> "C:\Program Files\Oracle\VirtualBox\VBoxManage" createhd --filename "C:\VM\RAC lab\london1\asm5.vdi" --size 4096 --format VDI --variant Fixed
    0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100% Medium created. UUID: 02a719b5-decf-4c16-9513-632c81e86896

        o Execute the following command to attach the disks to the VM. Each command is in a single line: (do it
           through GUI if necessary)


    C:>  "C:\Program Files\Oracle\VirtualBox\VBoxManage" storageattach london1 --storagectl "SATA" --port--device 0 --type hdd --medium "C:\VM\RAC lab\london1\asm1.vdi" --mtype shareable
    C:> "C:\Program Files\Oracle\VirtualBox\VBoxManage" storageattach london1 --storagectl "SATA" --port --device 0 --type hdd --medium "C:\VM\RAC lab\london1\asm2.vdi" --mtype shareable
    C:> "C:\Program Files\Oracle\VirtualBox\VBoxManage" storageattach london1 --storagectl "SATA" --port--device 0 --type hdd --medium "C:\VM\RAC lab\london1\asm3.vdi" --mtype shareable
    C:> "C:\Program Files\Oracle\VirtualBox\VBoxManage" storageattach london1 --storagectl "SATA" --port--device 0 --type hdd --medium "C:\VM\RAC lab\london1\asm4.vdi" --mtype shareable
    C:> "C:\Program Files\Oracle\VirtualBox\VBoxManage" storageattach london1 --storagectl "SATA" --port--device 0 --type hdd --medium "C:\VM\RAC lab\london1\asm5.vdi" --mtype shareable

        o Create partition from above added disks
         use fdisk command to partition the disks (as root).Repeat the steps below for all the disks ( sdb, sdc, sdd, sde,sdf).

    --- Repeat the same step for sdc, sdd and sde.
    [root@london1 ~]# fidsk /dev/sdb   
    Command (m for help): n
    Command action   e   extended   /   p   primary partition (1-4) p
    Partition number (1-4): 1
    First cylinder (1-652, default 1): <enter>
    Using default value 1
    Last cylinder, +cylinders or +size{K,M,G} (1-xxx, default xxx): <enter>
    Command (m for help): w
    The partition table has been altered!
    --- Final result
    [root@london1 ~]# ls -l /dev/sd?1
    brw-rw---- 1 root disk 8,  1 Jul 19 05:34 /dev/sda1
    brw-rw---- 1 root disk 8, 17 Jul 19 05:52 /dev/sdb1
    brw-rw---- 1 root disk 8, 33 Jul 19 05:53 /dev/sdc1
    brw-rw---- 1 root disk 8, 49 Jul 19 05:54 /dev/sdd1
    brw-rw---- 1 root disk 8, 65 Jul 19 05:54 /dev/sde1
    brw-rw---- 1 root disk 8, 65 Jul 19 05:54 /dev/sdf1

        o Configure the option -g for the scsi_id command to expect an UUID  from the shared devices.

    [root@london1]#  printf  "options=-g\n--whitelisted\n --replace-whitespace"  > /etc/scsi_id.config
    ----- Create a symbolic link for scsi_id
       ln -s  '/usr/lib/udev/scsi_id'   '/sbin/scsi_id'

        o Prepare the file /etc/udev/rules.d/99-oracle-asmdevices.rules by running the following script:

    [root@london1]#   i=1
    cmd="/sbin/scsi_id -g -u -d"
    for disk in sdb sdc sdd sde ; do
    cat <<EOF >> /etc/udev/rules.d/99-oracle-asmdevices.rules KERNEL=="sd?1", SUBSYSTEM=="block", PROGRAM=="$cmd /dev/\$parent", \
    RESULT=="`$cmd /dev/$disk`", SYMLINK+="asm-disk$i", OWNER="grid", GROUP="dba", MODE="0660"
    EOF
    i=$(($i+1))
    done
      
    - Note: Choose carefully the owner of the asm disks here (OWNER=grid if the installation uses grid user and OWNER=oracle if installation will be done through oracle user).
    The file content should look like the below:
    KERNEL=="sd?1", SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/scsi_id -g -u -d /dev/$parent", RESULT=="SATA_VBOX_HARDDISK_VBd306dbe0-df3367e3_", SYMLINK+="asm-disk1", OWNER="grid", GROUP="dba", MODE="0660"

        o Reload the udev rules and restart udev:

    [root@london1]#   /sbin/partprobe /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1
    [root@london1]#   /sbin/udevadm test /block/sdb/sdb1
    [root@london1]#   /sbin/udevadm test /block/sdc/sdc1
    [root@london1]#   /sbin/udevadm test /block/sdd/sdd1
    [root@london1]#   /sbin/udevadm test /block/sde/sde1
    [root@london1]#   /sbin/udevadm test /block/sde/sdf1
    [root@london1]#   /sbin/udevadm control --reload-rules
    [root@london1]#   /sbin/start_udev     ** Not needed for RHEL

        o Check the result
    [root@london1 ~]# ls -l /dev/asm-*
    brw-rw---- 1 grid dba 8, 17 Jul 19 07:28 /dev/asm-disk1
    brw-rw---- 1 grid dba 8, 33 Jul 19 07:28 /dev/asm-disk2
    brw-rw---- 1 grid dba 8, 49 Jul 19 07:28 /dev/asm-disk3
    brw-rw---- 1 grid dba 8, 65 Jul 19 07:28 /dev/asm-disk4
    brw-rw---- 1 grid dba 8, 65 Jul 19 07:28 /dev/asm-disk5


    4. Clone the node                                                                                     Go to Top


    Copy london1 VBOX hdrive rename it to london2  and start a new vm with a name london2 using existing london2.vdi.
    • Add virtual machine network configuration as
    • Adapter 1 (host only).
    • Adapt2 : internal network rac-priv.
    • Adapter3 (NAT).
    • Add shared file 12rc_RAC
    • Attach 4 previous ASM disks
    Second Node configuration LONDON2
     
         o Startup london2 node and run the network manager tool
    [root@london2] nmtui     in RHEL7 ---------OR #system-config-network in RHEL6  
     
      o Set the following
    • eth0 public IP to  192.168.78.52
    • eth1 Private IP to 172.16.100.52
    • eth2 DHCP address only 
    • Configure new device> dns configuration
    • Use london2.evilcorp.com as hostname

    o Remove the udev network rules file. It will be regenerated on the next reboot with the new MAC addresses.

    [root@london2 ~]# rm -f /etc/udev/rules.d/70-persistent-net.rules

         o Remove the HWADDR and UUID lines in the network adapter configuration files.

    [root @london2]# sed -i -e '/HWADDR/d' -e '/UUID/d' /etc/sysconfig/network-scripts/ifcfg-eth[0-2]

         o Complete DNS setup

    ------ Stop the DNS service
    [root@london2]# service named stop 
    ------ Remove the actual DNS files
    [root@london2]# rm -f /var/named/evilcorp.com /var/named/evilcorp.com.rev
    ----- Modify /etc/named.conf file
    [root@london2]# sed -i -e 's/listen-on .*/listen-on port 53 { 192.168.78.52; };/' \-e 's/type master;/type slave;\n masters {192.168.78.51; };/' \/etc/named.conf
    --- Check that the parameter PEERDNS is set to no in /etc/sysconfig/network-scripts/ifcfg-eth2---- start the DNS service
    [root@london2]#  service named start

    o Check that both DNS servers are working (master and slave) on the nodes. Make sure both nodes are up and runing

    [root@london2 ~]# netstat -tulpn | grep :53    ** port 53  is the DNS listener port
    [root@london2 ~]# dig @london1 london1.evilcorp.com
    [root@london2 ~]# dig @london1 london2.evilcorp.com
    [root@london2 ~]# dig @london1 london1-vip.evilcorp.com
    [root@london2 ~]# dig @london1 london2-vip.evilcorp.com
    [root@london2 ~]# dig @london1 london1-priv.evilcorp.com
    [root@london2 ~]# dig @london1 london2-priv.evilcorp.com
    [root@london2 ~]# dig @london1 london-cluster-scan.evilcorp.com
    [root@london2 ~]# dig @london2 london1.evilcorp.com
    [root@london2 ~]# dig @london2 london2.evilcorp.com
    [root@london2 ~]# dig @london2 london1-vip.evilcorp.com
    [root@london2 ~]# dig @london2 london2-vip.evilcorp.com
    [root@london2 ~]# dig @london2 london1-priv.evilcorp.com
    [root@london2 ~]# dig @london2 london2-priv.evilcorp.com
    [root@london2 ~]# dig @london2 london-cluster-scan.evilcorp.co
       
         o Confirm that the asm disk are present on node london2
       [root@london2 ~]$ ls -l /dev/asm-*
      
         o Setup the VNC Server on london1 and unzip the installation files
       [oracle@london1]$ vncserver :1 
         -- Desktop is london1.evilcorp.com:1
       

        o log on to london1 using  vncviewer [192.168.78.51:1] and unzip the install files
    [oracle@london1]$ su oracle   
    [oracle@london1]$  unzip V46096-01_1of2.zip -d  {/path/to/extract}
    [oracle@london1]$  unzip V46096-01_2of2.zip -d  {/path/to/extract}
    Do the same with Oracle Database files  : V46095-01_1of2.zip  V46095-01_2of2.zip  
      
       o Use the following command to install the cvuqdisk package on both nodes (this allows Cluster Verification Utility to find the shared disks during installation)
      [oracle@london1]$ rpm -Uvh grid/rpm/cvuqdisk-1.0.9-1.rpm
            
    o  Adjust the cvu_config  to avoid the pdksh "missing package"  pre-req failure
    [oracle@london1]$ sed -i 's/CV_ASSUME_DISTID=OEL5/CV_ASSUME_DISTID=OEL7/' grid/stage/cvu/cv/admin/cvu_config


    5. Install grid infrastructure 12c release 1                                             Go to Top


         o  Run Grid Cluster installer
    [oracle@london1]$    /media/sf_12cR1/grid/runInstaller
        
            Oracle_RAC_Database_12c_Lab_Grid_1Oracle_RAC_Database_12c_Lab_Grid_1.2

      o Note :  Since our SCAN Name chosen is too long (more than 15 chars.) Oracle will proposes to shorten it unless you choose  advanced installation (which we are doing here).
          Oracle_RAC_Database_12c_Lab_Grid_1.4
  • Scan nam : london-cluster-scan.evilcorp.com        cluster name : london-cluster
  • Oracle_RAC_Database_12c_Lab_Grid_config_1.4.2

  • Add public hostname london2.evilcorp.com
  • Add virtual hostname   london2-vip.evilcorp.com
  • Oracle_RAC_Database_12c_Lab_Grid_config_2.1

  • SSH conectivity : 
  • Establish passwordless ssh connectivity by typing oracle password and click setup  then Ok when finished
  • Oracle_RAC_Database_12c_Lab_Grid_config_2.2

  • Click identify network interface : eth0 :puclic , eth1: private ,eth2: do not use
  • Oracle_RAC_Database_12c_Lab_Grid_config_3       

  • Storage Option(advanced): select standard asm for storage

  • Oracle_RAC_Database_12c_Lab_Grid_config_3.1

  • Create asm disk group :
  •     -    Leave DATA as Disk Group Name.
        -    Select External redundancy
        -    If the Candidate Disks list is empty
        -   Click on Change Discovery Path.. Enter /dev/asm* in the Disk Discovery Path  text field.
          select 3 first disks (asm-disk1/2/3)

    Oracle_RAC_Database_12c_Lab_Grid_config_3.2
  • asm password racattack  (use the same password for both asm acounts)
  • Failure isolation (advanced ) : Do not use IPMI (inteligent platform management interface)
  • Operating system group : all default  dba /asmdba , asmoper

  • Oracle_RAC_Database_12c_Lab_Grid_config_3.5

  • Installation location :
  •          - ORACLE_BASE=/u01/app/grid
             - GRID_HOME=/u01/oracle/product/12.1.0.2/grid

    Oracle_RAC_Database_12c_Lab_Grid_config_3.6
             - Inventory = u01/app/OraIventory
    Oracle_RAC_Database_12c_Lab_Grid_config_3.7

  • Root script execution : Choose wether to run the rootscripts manually or allow the installer to do it automatically (with password)
  • Some prerequisite validation will be done at this step. It can require few minutes to complete.

    Oracle_RAC_Database_12c_Lab_Grid_config_4.2
  •        - In the example above the warnings can be ignored (tick the according check box)
            -  Click Install

  • Note :  you can save the installations setting into a responsefile for a future silent install
  • [oracle@london1]$ grid/runInstaller -silent -responseFile /home/grid/grid_rac_install.rsp -showProgress -promptForPassword    // -ignorePrereq
       
        o   FINAL STEP: root scripts:
    execute the iguration scripts on Both nodes as root  then click ok when finished

    [root@]$   /u01/app/oraInventory/orainstRoot.sh
    [root@]$   /u01/app/grid/product/12.1.0.2/grid/root.sh 
    [root@]$   /u01/app/grid/product/12.1.0.2/grid/crs/config/rootconfig.sh

         Oracle_RAC_Database_12c_Lab_Grid_config_4.3

  • Note: In case rootconfig.sh execution raise an error related to roothas/rootcrs  perl scripts path. Adjust it as follows

  • [root@]$ sed -i 's/perl -I$ORACLE_HOME\/perl\/lib -I$ORACLE_HOME\/crs/perl -I $ORACLE_HOME\/perl\/lib -I $ORACLE_HOME\/crs/' rootconfig.sh

    - This will change the two following lines
  • ROOTHASPL="$ORACLE_HOME/perl/bin/perl -I $ORACLE_HOME/perl/lib -I $ORACLE_HOME/crs/install $ORACLE_HOME/crs/install/roothas.pl"
  • ROOTCRSPL="$ORACLE_HOME/perl/bin/perl -I $ORACLE_HOME/perl/lib -I $ORACLE_HOME/crs/install $ORACLE_HOME/crs/install/rootcrs.pl"
  • Post-Installation

        o Execute configToolAllCommands as grid user on first node:


    [root@]$  $GRID_HOME/cfgtoollogs/configToolAllCommands

    6. Install the database software 12c release 1                                      Go to Top

       
        o INSTALL the DBMS software 

          -  Adjust the cvu_config  to avoid the "missing package"  pre-req failure  command
    [oracle@london1]$ sed -i 's/CV_ASSUME_DISTID=OEL4/CV_ASSUME_DISTID=OEL7/' database/stage/cvu/cv/admin/cvu_config

    Install database software only then click Next
  • > grid install options : Oracle RAC database installation
  • Oracle_RAC_Database_12c_Lab_DB_config_1.2

  • > Node selection : make sure ssh passwordless connection works, click Next

  • Oracle_RAC_Database_12c_Lab_DB_config_1.3

  • > Instal type Entreprise , click NEXT
  • Oracle_RAC_Database_12c_Lab_DB_config_1.4

  • > Installation location
  • Oracle Base: /u01/app/oracle  
  • Oracle home: /u01/app/oracle/product/12.1.0.2/db_1
  • Oracle_RAC_Database_12c_Lab_DB_config_1.5

  • > Operating system groups :  Leave dba for all groups except for the OSOPER group and click Next
  • >...check Prereq

  • Oracle_RAC_Database_12c_Lab_DB_config_1.6

             - In this example : one warning has a fix that I applied and the other has been ignorred during my     
                installation

         Oracle_RAC_Database_12c_Lab_DB_config_2.2
  • Run /u01/app/oracle/product/12.1.0.2/db_1/root.sh as root on both nodes london1,london2 then click ok when done.
  •    Oracle_RAC_Database_12c_Lab_DB_config_2.2

         o Possible installation failures and warnings :

      Warnings :

    Warning :
    SWAP too small+ /dev/shm not permanently mounted
    Fix  : make sure  /dev/shm is mounted in /etc/fstab
    Warning : PRVF-5056 : SCAN listener "LISTENER_SCAN1" not running  
     Fix :  Start the identified listener using ''srvctl start scan_listener
    Warning : Maximum locked memory check -- warning
     Fix  : [root@london2-1 ~]# /tmp/CVU_12.1.0.2.0_grid/runfixup.sh

      Failures :

    PRVG-1561 : Setting ORA_CRS_HOME variable is not supported        
    SOLUTION : $ unset ORA_CRS_HOME                                   
    PRVF-9661 : Time offset is greater than acceptable limit on node "london2" [actual = "-5200.0", acceptable = "1000.0" ]
    - Cause:  System clock has drifted from the clock on the reference node for the specified set of nodes. 
    - Action: If this is only generated by CTSSD ignore
    [oracle@london1]#   crsctl check ctss                                         [oracle@london2]# crsctl check ctss         
    CRS-4702: Offset (in msec): 0                                                    CRS-4702: Offset (in msec): –3100

    7. Create the 12c database on the cluster                                             Go to Top

      o  Create +FRA asm diskgroup first

       [grid@london1] oraenv
        [+ASM1]
       [grid@london1] sqlplus "/ as sysasm"
        SQL> CREATE DISKGROUP FRA EXTERNAL REDUNDANCY DISK '/dev/sde1','/dev/sdf1'  ; 
        SQL> Alter diskgroup FRA mount;

         o  Run the DBCA:

        [oracle@london1] /u01/app/oracle/product/12.1.0.2/db_1/bin/dbca
  • > Select create database
  • RA-Oracle_RAC_12101-DBCA_Database_Operation

  • > Select Create a database with default configuration.
  • >Global Database Name: RAC_DB.evilcorp.com
  • Storage Type: Automatic Storage Management (ASM)
    Database Files Location: +DATA
    Fast Recovery Area: +FRA
    Database Character Set: AL32UTF8 - Unicode UTF-8 Universal character set
    Administrative password: racattack
    Check Create As Container Database
    Pluggable Database Name: PDB(*)

    RA-Oracle_RAC_12101-DBCA_Creation_mode

    Click NEXT
  • The prerequisite checks may fail due to space requirements. It's safe to ignore by checking Ignore all. Click Next to see the summary
  • RA-Oracle_RAC_12101-DBCA_Summary

    Click Finish to start the installation


  • The database creation is finished. Click Exit, then Close.
  • Oracle_RAC_Database_12c_Lab_DBCA_4


    Note : Don’t forget to assign the right values to oracle_sid environment variable for both grid and oracle .bash_profile files in each nodes.  (i.e ORACLE_SID=Racdb1/Racdb2 …)


    o Possible installation failures and warnings

    I - LONDON2 PRCR 1079 fail to start resource  ora.rac_db.db
    ORA-00845 Memory target not supported CLNS 00107
    CRS-2674 srvctl start ora.rac_db -n london2 failed
    CRS-2632 no more servers

    Cause :
    The use of Automatic Memory Management (AMM)  is absolutely incompatible with HugePages.
    On systems with HugePages in use, attempting to set the MEMORY_TARGET / MEMORY_MAX_TARGET instance initialization parameters may result in the mentioned error message:
    ORA-00845: MEMORY_TARGET not supported on this system

    Solution  (if you want to keep AMM on) :
    On both nodes
          1 - Add transparent_hugepage=never  at the end of the below line  in the  /etc/default/grub file
        GRUB_CMDLINE_LINUX=...
          2- Apply change on each node london1 london2

    [root@]# grub2-mkconfig -o /boot/grub2/grub.cfg

          3-
    Reboot the system to ensure the huge pages setting takes effect properly.
    [root@]# cat /proc/cmdline
    [root@]# cat /sys/kernel/mm/transparent_hugepage/enabled
    [always] madvise never

    II -DBCA Failing ORA-12537: TNS: Connection closed During 12c RAC Installation

    Cause : Listener (including SCAN Listener) and Database are Owned by Different OS Users (oracle and grid)

    Solution: Make sure that the file system of the database home directory  has setuid/suid set, database binary($RDBMS_HOME/bin/oracle) has correct ownership and permission  and listener owner is able to access database oracle binary (as listener owner)
    # Repeat Following on Each Node of Cluster/Grid Infrastructure (london1, london2)

    [root@london1 ~]# cd /u01/app/oracle/product/12.1.0.2/db_1/bin[root@london1 bin]# ls -l
    oracle
    -rwxrwsr-x 1 oracle dba 323649880 Dec 22 02:53 oracle
    [root@london1 bin]# chmod 6775 oracle      
    -- first number in this command (6) means setting both setuid/suid and setgid/sgid options
    [root@london1 bin]# ls -l
    oracle
    -rwsrwsr-x 1 oracle dba 323649880 Dec 22 02:53 oracle

    7. Enjoy and experiment                                                                         Go to Top

    We can finaly check the current status of the cluster and the RAC database resource: 

    [grid@london1 ~]$ crsctl stat res ora.rac_db.db -t
    --------------------------------------------------------------------------------
    Name           Target  State        Server                   State details
    --------------------------------------------------------------------------------
    Cluster Resources
    --------------------------------------------------------------------------------
    ora.rac_db.db
           1        ONLINE  ONLINE       london1                  Open,STABLE
           2        ONLINE  ONLINE       london2                  Open,STABLE
    --------------------------------------------------------------------------------

    # [root@london2 bin]# srvctl status database -d Rac_DB

    Instance RACDB1 is running on node london1
    Instance RACDB2 is running on node london2

    For a better preview of the RAC 12c features I invite you to explore it in my next post  >> Enjoy and experiment