# Apply SRV priority before weight when selecting a service endpoint > Use RFC 2782 — A DNS RR for specifying the location of services (DNS SRV) to review this narrow operational decision without extending the source beyond its stated scope. - Canonical URL: https://update.dsesecurity.com/updates/apply-srv-priority-before-weight-when-selecting-a-service-endpoint/ - Publisher: Detection Systems & Engineering (DSE Security) - Author: DSE Security Editorial Team - Published: 2026-08-27T12:17:54+00:00 - Modified: 2026-08-27T12:18:09+00:00 - Last reviewed by DSE: 2026-08-26 - Resource type: Checklist - DSE priority: Advisory - Topics: Cybersecurity, Networks & Infrastructure - Reading time: 3 minutes ## What you need to know Use RFC 2782 — A DNS RR for specifying the location of services (DNS SRV) to review this narrow operational decision without extending the source beyond its stated scope. ## Potentially affected Teams, systems, services, or facilities within the stated scope of RFC 2782 — A DNS RR for specifying the location of services (DNS SRV) ## DSE recommendation Compare the observed state with the cited official source, document applicability and exceptions, and test any approved change with rollback safeguards. ## Article Treat this document as a focused evidence review: Apply SRV priority before weight when selecting a service endpoint. Only the official source and traced locations below supply facts. Confirm applicability before acting. ## Source fact: The official [RFC 2782 — A DNS RR for specifying the location of services (DNS SRV)](https://www.rfc-editor.org/rfc/rfc2782.html) from RFC Editor / Internet Engineering Task Force supports the following bounded statements: - An SRV record identifies a service endpoint with priority, weight, port, and target fields. The research record locates this support at Section The format of the SRV RR. - A client first selects reachable SRV targets with the lowest priority value, then uses weight to choose among targets at that priority. The research record locates this support at Section Usage rules. - Within one priority group, a target’s selection chance is proportional to its weight relative to the sum of that group’s weights. The research record locates this support at Section Usage rules, weighted selection procedure. Keep the evidence boundary at these traced claims. They support a review of authoritative zones, delegations, resolvers, caches, record owners, and the clients that consume the resulting answers; they do not support conclusions outside the source’s stated conditions. ## What the source does not establish This RFC evidence supports only the named DNS protocol decision; it does not prove Windows implementation support or a safe production configuration. It does not establish a deployment’s current state, authorize a production change, prove compliance, or show that Windows DNS roles, Active Directory-integrated data, forwarding paths, time, routing, firewalls, and registrar or registry state are healthy. Documented options are review inputs, not universal mandates. ## Applicability questions - For source statement 1 at Section The format of the SRV RR, which observable configuration, record, or test can confirm applicability here? - For source statement 2 at Section Usage rules, which observable configuration, record, or test can confirm applicability here? - For source statement 3 at Section Usage rules, weighted selection procedure, which observable configuration, record, or test can confirm applicability here? - Within authoritative zones, delegations, resolvers, caches, record owners, and the clients that consume the resulting answers, which versions, roles, and configuration states define the review population? - Could Windows DNS roles, Active Directory-integrated data, forwarding paths, time, routing, firewalls, and registrar or registry state invalidate the test, hide a failure, or change applicability? - Who owns the decision, and which observation requires stopping, escalation, or rollback? ## DSE recommendation: DSE recommends using the cited source as the evidence anchor for this decision. Anchor the review in the cited section and keep observation separate from interpretation. Record the source location, examined part of authoritative zones, delegations, resolvers, caches, record owners, and the clients that consume the resulting answers, observed and expected states, owner, and reason for deviation. If the review warrants change, use a bounded implementation with prerequisites, test population, monitoring, abort criteria, and a rehearsed reversal. Sequence checks for Windows DNS roles, Active Directory-integrated data, forwarding paths, time, routing, firewalls, and registrar or registry state and sanitize protected material before retention. ## Verification and evidence Keep the source locations Section The format of the SRV RR; Section Usage rules; Section Usage rules, weighted selection procedure adjacent to the sanitized artifacts used for comparison. Prefer zone data, packet captures, query transcripts, delegation checks, resolver configuration, and negative-answer behavior, with enough identity and timing data for an independent recheck. Close the review only when the evidence, exception handling, resulting action, and after-state are linked. Schedule a new review after material technical, organizational, incident, or source changes; today’s observation is not a continuing guarantee. ## Official references - [RFC 2782 — A DNS RR for specifying the location of services (DNS SRV)](https://www.rfc-editor.org/rfc/rfc2782.html) — RFC Editor / Internet Engineering Task Force ## Primary reference - Name: RFC 2782 — A DNS RR for specifying the location of services (DNS SRV) - Authority: www.rfc-editor.org - URL: https://www.rfc-editor.org/rfc/rfc2782.html - Source publication date: Not stated by the source ## Citation and use Preferred citation: “Apply SRV priority before weight when selecting a service endpoint,” DSE Security, https://update.dsesecurity.com/updates/apply-srv-priority-before-weight-when-selecting-a-service-endpoint/ Publishing principles: https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/ Usage and citation policy: https://update.dsesecurity.com/usage/ Copyright © 2026 Detection Systems & Engineering. 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