(Failover Cluster) DNS의 역할

✅ Is DNS Used in Live Migration?

✅ Yes — for initial node resolution and authentication

When you initiate a Live Migration in a Windows Failover Cluster:

1. The initiating node (source) needs to:
   • Contact the destination node (target).
   • Authenticate using Kerberos (via domain controller).
   • Establish a SMB (or SMB Direct) connection for memory transfer.
2. For this to work:
   • The node resolves the destination node’s hostname via DNS.
   • Kerberos auth requires reaching the Domain Controller (DC) — and that also usually needs DNS.

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🔄 When Is DNS Not Needed?

Once the connection is established (SMB session over IP), DNS is no longer needed.

• The actual memory transfer and disk handling happen over IP.
• So if DNS fails after the connection, the Live Migration can still proceed.

But if the initiating node cannot resolve the target node's name or reach the DC via DNS, then:

• ❌ The Live Migration will fail.
• ❌ Kerberos authentication won't complete.