What does the 's' flag mean in a NAPTR record?

The 's' flag signifies that the next lookup step is terminal and points directly to an SRV record specified in the replacement field.

Updated: August 2026 • Verified v1.2

DNS RFC 3403 NAPTR (Naming Authority Pointer) Record Generator

Internet & NetworkNetwork

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[domain]. IN NAPTR [order] [preference] "[flags]" "[service]" "[regexp]" [replacement]

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Understanding Your Results

Generates valid RFC 3403 NAPTR records from user inputs or industry presets (SIP TLS, SIP UDP, ENUM E.164, SIP WebSockets), with terminal `dig` verification commands.

Practical Guidance & Next Steps

In NAPTR records, lower `order` values are processed first. For identical `order` values, lower `preference` acts as the tie-breaker. Flag `s` indicates a terminal lookup for an SRV record.

What is this?

A network telecommunications utility that creates RFC 3403 Naming Authority Pointer (NAPTR) DNS records for VoIP and telephony routing.

How does it work?

1. Enter domain or select a preset (SIP TLS, SIP UDP, ENUM). 2. Customize order, preference, flags, and replacement target. 3. Copy the formatted BIND zone record and terminal verification query.

Why use it?

Eliminates syntax errors when configuring PBX telecommunications and VoIP service discovery.

Technical Scope & Calculation Limitations

Generates standard RFC 3403 BIND zone file format.

Frequently Asked Questions

A NAPTR (Naming Authority Pointer) record is a specialized DNS resource record defined in RFC 3403. It allows regular expression-based rewriting of domain names or phone numbers to map into service endpoints like SIP or SRV records.

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