Multi Tenancy and Isolation Questions

Cover architectural patterns and operational practices for supporting multiple tenants or workload groups in the same infrastructure. Discuss tenancy models such as dedicated hardware, dedicated virtual networks, shared clusters with logical isolation, database per tenant, schema per tenant, and shared schema with tenant identifiers. Address isolation mechanisms including network segmentation, identity and access management, namespace isolation, resource quotas, billing and chargeback, noisy neighbor mitigation, tenant onboarding and lifecycle, tenancy migration, monitoring per tenant, and the tradeoffs between cost, security, and operational complexity.