{"id":12200,"date":"2025-08-25T07:55:02","date_gmt":"2025-08-25T14:55:02","guid":{"rendered":"https:\/\/blogs.infoblox.com\/?p=12200"},"modified":"2025-09-08T08:17:07","modified_gmt":"2025-09-08T15:17:07","slug":"rethinking-critical-infrastructure-the-strategic-case-for-decoupling-dns-dhcp-from-identity-services","status":"publish","type":"post","link":"https:\/\/www.infoblox.com\/blog\/company\/rethinking-critical-infrastructure-the-strategic-case-for-decoupling-dns-dhcp-from-identity-services\/","title":{"rendered":"Rethinking Critical Infrastructure: The Strategic Case for Decoupling DNS\/DHCP from Identity Services"},"content":{"rendered":"

In today\u2019s interconnected enterprise environments, the stability and security of network services and infrastructure directly impact business continuity and resilience. Among the most critical yet often overlooked components of the network are Domain Name System (DNS) and Dynamic Host Configuration Protocol (DHCP) services. These services form the foundation upon which virtually all digital operations depend. Many organizations default to using the DNS and DHCP services bundled with Microsoft Active Directory, because of the convenience and perceived ease of deployment during domain controller setup. However, this architecture warrants reconsideration in light of evolving threat landscapes and increasing operational demands. <\/p>\n

The True Criticality of DNS and DHCP <\/h3>\n

DNS (think of it as the GPS for computers to find websites and services) and DHCP (think automatic assignment of IP\/network addresses to computers) aren\u2019t merely background services\u2014they are the mission-critical foundation of your entire digital infrastructure. Every enterprise application and security tool in your enterprise relies on DNS as its digital lifeline. Without DNS resolution, applications simply cannot communicate, rendering even the most sophisticated systems inoperable. <\/p>\n

When DNS or DHCP fails, the consequences aren\u2019t minor inconveniences\u2014they\u2019re potentially catastrophic events that can escalate to boardroom-level crises. In the most severe cases, complete DNS failure can halt operations across an organization: no transactions, no communications, no operations\u2014everything freezes. <\/p>\n

Given this level of criticality, the question becomes: are you architecting these services with the resilience they deserve? <\/p>\n

The Hidden Risk: Cascading Failures<\/h3>\n

Despite the critical role, DNS and DHCP services are often deployed alongside identity services on the same servers\u2014creating tightly coupled dependencies that can lead to dangerous cascading failures across the network. A recent ransomware event at a large healthcare organization illustrated this exact risk. First, the identity service was compromised, giving the attackers privileged access. Because DNS and DHCP were hosted on the same server as identity services, the organization simultaneously lost network access\u2014bringing down core operations and severely complicating recovery efforts. Without these foundational services, even basic troubleshooting became impossible, dramatically amplifying the disruption and prolonging the outage. <\/p>\n

Deploying DNS\/DHCP and identity services on the same server is the digital equivalent of housing a power plant control room and a city\u2019s emergency services dispatch center in the same building. When that building is attacked or compromised, you don\u2019t just lose electricity\u2014you lose the ability to coordinate a response. <\/p>\n

The Hidden Costs of Using DNS\/DHCP Bundled with Identity Services<\/h3>\n

Beyond catastrophic events, there are significant and often underestimated operational costs associated with running DNS and DHCP alongside identity services on the same infrastructure. <\/p>\n

The experience of a global energy company with 62,000 employees and annual revenue of $349 billion in 2024 illustrates this point. The organization maintained 400 servers that supported both DNS\/DHCP and identity services, all of which required monthly security and other patches\u2014totaling 4,800 patches annually. They had at least a 1 percent failure rate during patch cycles, leading to 48 crashes per year. Assuming each crash disrupted about 50 employees for an average of four hours, and applying a modest cost of $100 per hour per employee, these routine disruptions cost nearly $1 million in annual productivity losses. <\/p>\n

The impact wasn\u2019t limited to downtime. The company also had 15 full-time system administrators focused solely on managing and maintaining DNS\/DHCP on the combined infrastructure\u2014resources that could have been redirected toward higher-value, strategic initiatives that drive innovation and competitive differentiation. <\/p>\n

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Figure 1. Tightly coupled infrastructure: When DNS\/DHCP and identity services share the same servers, a single point of failure can cascade across your entire network, disrupting operations and complicating recovery efforts. <\/p>\n

Security Implications: Beyond Operational Risk<\/h3>\n

Security concerns further reinforce the need to separate DNS and DHCP from identity infrastructure. Advanced persistent threats like Volt Typhoon\u2014which target U.S. critical infrastructure including energy, water and telecommunications\u2014frequently begin by compromising centralized identity systems. These attacks often follow a \u201clive-off-the-land\u201d approach that leverages existing tools to avoid detection. <\/p>\n

Their strategic goal of such adversaries is to gather as much intelligence as possible\u2014including credentials and DNS\/DHCP data\u2014to execute their operation. When identity services and network services are tightly coupled on the same platform, the attack surface expands significantly: compromising one system can provide access to both authentication controls and foundational network functions. <\/p>\n

Separating these services, however, introduces a cleaner separation of responsibilities and enables adherence to the principle of least privilege. DNS and DHCP can function without elevated administrative rights, reducing the number of privileged accounts and limiting the potential impact of credential-based attacks. This architectural discipline is supported by recent draft updates to the National Institute of Standards and Technology (NIST) Special Publication 800-81<\/a>, which emphasize the importance of separating mission-critical services to enhance cyber resiliency. <\/p>\n

The Wake-Up Call: Critical Infrastructure Failures<\/h3>\n

In July 2024, the CrowdStrike incident served as a stark reminder of infrastructure dependencies. What began as a routine security update became the largest IT outage in history,1<\/sup> crippling millions of servers that hosted identity services alongside DNS and DHCP functions. The widespread impact occurred because the affected servers were responsible for essential authentication and core network connectivity. <\/p>\n

The cascading effects were unprecedented. Mission-critical applications were paralyzed across multiple sectors\u2014over 10,000 flights grounded, hospital operations disrupted and emergency services compromised. This wasn\u2019t just a technical glitch; it exposed the operational fragility of environments where DNS, DHCP and identity services are tightly coupled on the same infrastructure. <\/p>\n

A Strategic Transformation: Learning from Leaders<\/h3>\n

A leading global SaaS provider with 72,000+ employees and nearly $38 billion revenue\u202foffers a compelling case study in infrastructure modernization. The organization faced a series of urgent challenges\u2014including network outages when their identity and DNS services were impacted during the CrowdStrike incident, limited visibility across hybrid environments and a looming cloud migration deadline. To address these issues, they needed a more resilient and decoupled network architecture. <\/p>\n

Their transition to the Infoblox Universal DDI platform delivered several key benefits: <\/p>\n