ORACLE 19c RAC INSTALLATION GUIDE

                                           ORACLE 19c RAC

INSTALLATION GUIDE

With Real Installation Screenshots

Grid Infrastructure  •  ASM Disk  •  DNS/SCAN  •  Oracle Database

1. GRID INFRASTRUCTURE INSTALLATION

 

Steps 1–5: OS Installation, Network, Firewall & Oracle Pre-install

S.NO	STEPS / COMMANDS	DESCRIPTION
1	OEL 7.9 Installation	Install Oracle Enterprise Linux 7.9 on Node1 and Node2.
2	Configure: PUBLIC / PRIVATE / INTERNET	Set up three NICs: Public (SSH), Private (RAC interconnect), Internet.
3	systemctl stop firewalld systemctl disable firewalld	Disable firewall permanently on both nodes.
4	yum install -y oracle-database-preinstall-19c	Installs Oracle user, sets kernel params, installs dependency packages.
5	passwd oracle	Set password for oracle OS user.

 

Figure: Steps 4–5: oracle-database-preinstall-19c installation & oracle password setup

Steps 6–12: ASM Packages, Groups & Users

S.NO	STEPS / COMMANDS	DESCRIPTION
6	yum install -y oracleasm-support rpm -qa | grep oracleasm-support	oracleasm-support: tools to configure/manage ASM devices and init scripts.
7	yum install -y kmod-oracleasm	Kernel module for Oracle ASM. Provides oracleasm configure/init/scandisks.
8	groupadd asmadmin	ASM admin group: SYSASM, start/stop ASM, create/drop disk groups.
9	groupadd asmdba	ASM DBA group: database instances access ASM disks.
10	useradd -u 54323 -g oinstall -G asmadmin,asmdba grid	Create GRID user with UID 54323 for cluster-wide consistency.
11	getent group asmadmin # asmadmin:x:54331:grid	Verify groups created and grid user is a member.
12	passwd grid	Set password for GRID OS user.

 

Figure: Steps 8–12: Creating asmadmin/asmdba groups, grid user, oracle user group assignments

Steps 13–19: User Permissions, Directories, .bash_profile & ASMLib

S.NO	STEPS / COMMANDS	DESCRIPTION
13	usermod -a -G asmdba oracle usermod -G backupdba,dba,oinstall,racdba,kmdba,dgdba,oper oracle	Add oracle to all required OS groups for full DBA privileges.
14	mkdir -p /u01/app/oracle/product/19C/dbhome chown -R oracle:oinstall /u01 chmod -R 775 /u01 mkdir -p /u02/app/grid/product/19C/dbhome chown -R grid:oinstall /u02 chmod -R 775 /u02	Create ORACLE_HOME & GRID_HOME, set ownership and 775 permissions.
16	# GRID .bash_profile: export ORACLE_BASE=/u02/app/gridbase export ORACLE_HOME=/u02/app/grid/product/19C/dbhome export ORACLE_SID=+ASM1 source .bash_profile	Grid user env: ORACLE_HOME → Grid home, SID → +ASM1 (ASM instance).
17	# ORACLE .bash_profile: export ORACLE_BASE=/u01/app/oraclebase/ export ORACLE_HOME=/u01/app/oracle/product/19C/dbhome export ORACLE_SID=prim1 source .bash_profile	Oracle user env: ORACLE_HOME → DB home, SID → prim1.
18	oracleasm configure -I # User: grid | Group: oinstall # Start on boot: y | Scan on boot: y	Configure ASMLib driver owner, group and boot settings.
19	/usr/sbin/oracleasm init # Mounts /dev/oracleasm filesystem	Initialize and mount Oracle ASMLib driver filesystem.

 

2. ASM DISK CONFIGURATION

 

S.NO	STEPS / COMMANDS	DESCRIPTION
20	SHUT DOWN NODE1 & NODE2	Power off both VMs before adding shared disks.
21	VirtualBox > File > Virtual Media Manager > SHAREABLE	Mark each data disk as Shareable so both nodes can attach it.
22	fdisk -l # sda:100G sdb:10G sdc:10G sdd:10G # sde:5G  sdf:5G  sdg:5G	List disks to confirm 6 shared disks are visible.
23	fdisk /dev/sdb → n → p → [Enter]×3 → w # Repeat for sdc, sdd, sde, sdf, sdg	Create one primary partition on each data disk.
24	oracleasm createdisk DISK1 /dev/sdb1 oracleasm createdisk DISK2 /dev/sdc1 ... (DISK3–DISK6) oracleasm listdisks  # shows DISK1–DISK6	Label each partition as an ASM disk.
25	cd /dev/oracleasm/disks/ && ll # brw-rw---- 1 grid oinstall DISK1–6	Verify ASM disk ownership under /dev/oracleasm/disks/.
26	POWEROFF NODE1 > ATTACH DISKS TO NODE2 > START NODE2	Attach Node1 shared disks to Node2 in VirtualBox.
27	oracleasm listdisks   # on node2 # If missing: oracleasm scandisks	Verify all 6 ASM disks visible on Node2.

 

Figure: Steps 18–24: ASMLib configure/init, createdisk and listdisks output

3. DNS & SCAN CONFIGURATION

 

S.NO	STEPS / COMMANDS	DESCRIPTION
28	vi /etc/hosts  # on BOTH nodes # Public: 192.168.56.71/72 # Private: 192.168.10.1/2 # VIP: 192.168.56.81/82 # SCAN: 192.168.56.91/92/93	Configure /etc/hosts with all 4 IP types on both nodes.
29	yum install dnsmasq chkconfig dnsmasq on vi /etc/resolv.conf   nameserver 127.0.0.1   search homelab.org   nameserver 8.8.8.8	Install dnsmasq and set nameserver to localhost so SCAN IPs resolve.
30	vi /etc/scanipaddress 192.168.56.91/92/93  node-scan.homelab.org	Document all 3 SCAN IPs.
31	vi /etc/dnsmasq.conf address=/node-scan.homelab.org/192.168.56.91 address=/node-scan.homelab.org/192.168.56.92 address=/node-scan.homelab.org/192.168.56.93	Configure dnsmasq to resolve SCAN to all 3 IPs.
32	chattr +i /etc/resolv.conf	Lock resolv.conf against accidental DHCP overwrite.
33	service dnsmasq restart	Restart dnsmasq to apply configuration.
34	reboot	Reboot both nodes to apply all changes.
35	nslookup node-scan # Returns: 192.168.56.91/92/93	Verify SCAN resolution returns all 3 IPs.

 

Figure: Steps 28–35: /etc/hosts configuration and nslookup SCAN verification

4. GRID SOFTWARE & CLUSTER SETUP

 

S.NO	STEPS / COMMANDS	DESCRIPTION
36	ip addr show | grep inet ip link set enp0s9 up	Verify all 3 network interfaces are UP on both nodes.
37	unzip LINUX.X64_193000_grid_home.zip -d $ORACLE_HOME	Upload and unzip Grid Infrastructure software as grid user.
38	export CV_ASSUME_DISTID=OL8	Bypass OEL7/OL8 compatibility check.
39	vi /etc/ssh/sshd_config   PermitRootLogin yes   UseDNS no	Enable root SSH login and disable DNS lookup for SSH.
40	./sshUserSetup.sh -user grid -hosts "node1 node2"   -noPromptPassphrase -confirm -advance	Set up passwordless SSH for grid user between both nodes.
41	./runcluvfy.sh stage -pre crsinst   -n node1,node2 -verbose	Run Cluster Verification Utility – must pass all checks.
42	# SSH error workaround: mv /usr/bin/scp /usr/bin/scp.orig echo '/usr/bin/scp.orig -T $*' > /usr/bin/scp chmod 755 /usr/bin/scp	Fix for scp protocol errors during installation.
43	rpm -ivh cvuqdisk-1.0.10-1.rpm  # node1 scp cvuqdisk... root@node2:/tmp rpm -ivh cvuqdisk...  # node2	Install cvuqdisk on BOTH nodes.
44	systemctl status chronyd systemctl enable chronyd systemctl start chronyd	Ensure time sync (chrony/NTP) running on both nodes.
45	export CV_ASSUME_DISTID=OL8	Re-export before launching gridSetup.
46	cd $ORACLE_HOME ./gridSetup.sh	Launch Grid Infrastructure installer GUI.

 

Figure: Steps 40–41: Passwordless SSH setup for grid user and cluvfy pre-check passing

Grid Infrastructure Installer Wizard (./gridSetup.sh)

Figure: gridSetup.sh Step 1: Select 'Configure Oracle Grid Infrastructure for a New Cluster'

Figure: gridSetup.sh Step 2: Select 'Configure an Oracle Standalone Cluster'

Figure: gridSetup.sh Step 3: Cluster Name 'homelab-cluster' and SCAN name 'node-scan.homelab.org'

Figure: gridSetup.sh Step 7: ASM Disk Group 'DATA' – select DISK1, DISK2, DISK3

Running root.sh after Grid Installation

Figure: Step 46 (post): Running orainstRoot.sh and root.sh as root on Node1 – Clusterware stack started

5. ORACLE DATABASE INSTALLATION

 

S.NO	STEPS / COMMANDS	DESCRIPTION
47	unzip LINUX.X64_193000_db_home.zip -d $ORACLE_HOME	Upload Oracle 19c Database software and unzip to ORACLE_HOME.
48	./sshUserSetup.sh -user oracle -hosts "node1 node2"   -noPromptPassphrase -confirm -advance	Set up passwordless SSH for oracle user between both nodes.
49	./runInstaller	Launch Oracle Database installer GUI. Select RAC, use ASM storage.
50	dbca	Create RAC database using DBCA wizard. Set SID prefix, passwords, character set.

 

Figure: Steps 47–49: Oracle DB software unzip, SSH setup and runInstaller with root.sh

Figure: Step 50: DBCA – Creating Oracle 19c RAC database (prim1/prim2) on ASM storage

TROUBLESHOOTING: SSH CONNECTION ISSUES

 

Recreate id_rsa Key Pair cd ~/.ssh ssh-copy-id -i ~/.ssh/id_rsa.pub grid@node1 ssh -i ~/.ssh/id_rsa grid@node1	Fix Permissions chmod 600 ~/.ssh/id_rsa chmod 700 ~/.ssh chmod 600 ~/.ssh/authorized_keys
Backup & Clean Old Keys cp ~/.ssh/authorized_keys ~/.ssh/authorized_keys.bak > ~/.ssh/authorized_keys	Verify & Test SSH ssh node1 date ssh node2 date ssh -o BatchMode=yes grid@node2 echo 'SSH OK'
Copy Fresh Keys from BOTH Nodes (grid user) On node1: ssh-copy-id -i ~/.ssh/id_rsa.pub grid@node1 ssh-copy-id -i ~/.ssh/id_rsa.pub grid@node2 On node2: ssh-copy-id -i ~/.ssh/id_rsa.pub grid@node1 ssh-copy-id -i ~/.ssh/id_rsa.pub grid@node2