Oracle requires 3 dedicated SCAN IPs for the RAC cluster. These IPs must be: - Not assigned to any machine Not assigned to any machine - Not pingable Not pingable - Reserved exclusively for SCAN Reserved exclusively for SCAN If you enter SCAN IPs that are already used by VirtualBox, a VM, or any other device, the installer immediately throws the error.

You must select three fresh, unused IP addresses from your network range. Since your network is: 192.168.56.x Run ping on 3 IPs that are not in use: If the result shows: or ➡️ These IPs are free. ➡️ Use these three as your SCAN IPs .

Once you confirm free IPs, update the /etc/hosts file on both nodes . Below is the complete recommended hosts file for a 2-node RAC setup:

> Replace IPs with your real ones. This is based on your environment where: node1: 192.168.56.91 node2: 192.168.56.92 SCAN IPs: 192.168.56.101–103 Public, Private, VIP included Replace IPs with your real ones. This is based on your environment where: - node1: 192.168.56.91 node1: 192.168.56.91 - node2: 192.168.56.92 node2: 192.168.56.92 - SCAN IPs: 192.168.56.101–103 SCAN IPs: 192.168.56.101–103 - Public, Private, VIP included Public, Private, VIP included

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127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6

# Public
192.168.56.71 node1.learnomate.org node1
192.168.56.72 node2.learnomate.org node2

# Private
192.168.10.1 node1-priv.learnomate.org node1-priv
192.168.10.2 node2-priv.learnomate.org node2-priv

# Virtual
192.168.56.81 node1-vip.learnomate.org node1-vip
192.168.56.82 node2-vip.learnomate.org node2-vip

# SCAN (use free IPs)
192.168.56.101 node-scan.learnomate.org node-scan
192.168.56.102 node-scan.learnomate.org node-scan
192.168.56.103 node-scan.learnomate.org node-scan

Restart the installer and proceed. The error will be resolved because the installer now sees: ✔ Unique SCAN name ✔ 3 free SCAN IPs ✔ Correct hostname mapping

- SCAN IPs must not be used by any machine. SCAN IPs must not be used by any machine. - SCAN works as a round-robin DNS entry; that’s why all 3 resolve to the same name. SCAN works as a round-robin DNS entry; that’s why all 3 resolve to the same name. - Never assign SCAN IPs to any interface manually. Never assign SCAN IPs to any interface manually. Learn with Learnomate Technologies – Your Path to Smarter IT Skills Want to see how we teach? Head over to our YouTube channel for insights, tutorials, and tech breakdowns: www.youtube.com/@learnomate To know more about our courses, offerings, and team: Visit our official website: www.learnomate.org Interested in mastering Oracle Database Administration? Check out our comprehensive Oracle DBA Training program here: https://learnomate.org/oracle-dba-training/ Want to explore more tech topics? Check out our detailed blog posts here: https://learnomate.org/blogs/ And hey, I’d love to stay connected with you personally! Let’s connect on LinkedIn: Ankush Thavali 😎