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Use representative names from the target inventory. The checker is syntax-only and performs no DNS lookup.
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{{ sourceStatus || 'Drop one TXT, CSV, or LOG file up to 1 MiB onto the textarea.' }}
Auto detect resolves each nonblank line independently and records the resolved source kind in the ledger.
Choose the actual consumer of these names; DNS storage can allow more forms than host or platform naming policies.
Example target: dc01-rtr-edge-01. Invalid expressions stop the review instead of silently skipping policy.
Use the host label when the organization convention describes the asset name rather than its DNS zone.
Choose whether uppercase is blocking, review-only, or accepted for non-Kubernetes profiles.
Leave blank to disable suffix policy. A leading or trailing dot is normalized for comparison.
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The default review policy preserves the current audit result when Advanced is opened without edits.
InputNormalized hostnameSource kindOutcomeFailed or review rulesEvidenceCopy
{{ row.input }}{{ row.hostname }}{{ row.source_kind }}{{ outcomeLabel(row.outcome) }}{{ row.rules }}{{ row.evidence }}
PriorityFindingAffectedExampleSuggested next stepCopy
{{ row.priority }}{{ row.finding }}{{ row.affected }}{{ row.example }}{{ row.next_step }}
dnsmasq DHCP Config Generator Generate a dnsmasq IPv4 DHCP scope with CIDR and pool checks plus reservations, client options and optional PXE lines for a review-ready config.
Filebeat Grok Pattern Generator Turn one representative log line into a Filebeat-ready Grok pattern with ECS-aware fields, local match checks, and optional ingest pipeline JSON.
DNS Zone File Generator Draft a BIND or provider-ready DNS zone file with normalized records, SOA and TTL checks, plus mail and DNSSEC review warnings.
Reverse DNS (PTR) Checker Check PTR records for an IP or hostname, verify forward-confirmed reverse DNS, and compare expected names or public resolver views.

Names that work in one system can fail in another. DNS comparisons may accept uppercase letters, an automation convention may require lowercase, Kubernetes narrows the allowed shape further, and an organization may encode site, role, service, and sequence in a regular expression. A naming review must separate protocol syntax from local policy instead of treating every convention as an Internet rule.

A fully qualified domain name contains labels separated by dots. Each label identifies one level of the DNS hierarchy, while the leftmost label often carries the machine or workload name. That distinction matters when a convention should match only dc01-rtr-edge-01 rather than the complete dc01-rtr-edge-01.example.internal.

ContextWhat it constrainsCommon reason to choose it
Hostname or FQDNOne or more DNS-style labelsServer inventories and ordinary host identities
Single host labelExactly one label without dotsShort names stored separately from a DNS suffix
Kubernetes nameLowercase DNS-style label or subdomain rulesNames consumed directly by Kubernetes resources
Organization patternRFC-style syntax plus a chosen regular expressionAsset names that encode operational meaning

Passing a syntax review does not mean the name exists in DNS, reaches the intended host, matches a certificate, or belongs to the right asset. Renaming also affects monitoring, SSH trust, certificates, local host mappings, configuration management, and application references. Treat the result as input to a controlled rename or inventory cleanup, not as proof that the wider system is ready.

Internationalized names need a separate Internationalized Domain Names in Applications (IDNA) conversion step. This review accepts ASCII hostname presentation and reports Unicode labels as syntax failures rather than silently converting them to Punycode.

How to Use This Tool:

Choose the profile used by the system that will consume the names, then audit a representative inventory.

  1. Paste Hostname inventory as one nonblank item per line, or drop a TXT, CSV, or LOG file up to 1 MiB. Use no more than 500 entries.
  2. Choose Input format. Auto detect handles absolute URLs, host assignments, CSV first columns, and plain hostname lines; pin a format when a copied line could be read more than one way.
  3. Select Standards profile. For organization profiles, enter a valid Naming regex and choose whether it applies to the first host label or the full hostname.
  4. Set Lowercase policy, an optional Required suffix, and the duplicate policy. Kubernetes profiles require lowercase regardless of the separate lowercase setting.
  5. Review Hostname ledger for the exact evidence, then use the remediation queue to group affected names by rule. Fix an invalid regex or suffix first because either one stops the review.

Interpreting Results:

Pass means the normalized name has no finding under the selected profile and policies. Review means only a review-level rule, such as the default duplicate policy or optional uppercase warning, was triggered. Fail means at least one blocking extraction, syntax, regex, case, suffix, or duplicate rule failed.

The overall gate passes only when every row passes; one Review row keeps it from passing. A high pass rate can still hide a small number of consequential failures, so use the ledger and remediation queue rather than relying on the percentage alone. DNS resolution, reachability, and ownership remain separate checks.

Technical Details:

The review first extracts one candidate hostname per nonblank line, removes wrapping quotes and a trailing root dot, strips a numeric port from a plain host value, and then applies syntax and policy rules. The original line remains available beside the normalized hostname so a bad extraction can be traced back to its source.

Transformation Core:

Input mode controls only how the candidate hostname is extracted. It does not weaken the selected hostname profile.

Input modeExtraction path
Hostname listUse the complete trimmed line as the candidate.
URL listRequire an absolute URL and extract its hostname.
CSV first columnParse quoted CSV cells and use the first column.
Auto detectTry a host assignment, then an absolute URL, then a CSV first column, otherwise use the first whitespace-delimited token.

A suffix is lowercased and trimmed of leading or trailing dots. A candidate matches when it equals the suffix or ends with a dot followed by that suffix, so notexample.internal does not satisfy example.internal. Duplicate comparison is also case-insensitive.

Rule Core:

Syntax is evaluated in UTF-8 bytes. The limits below apply to the displayed hostname without a final root dot.

RuleExact behavior
Total lengthAt most 253 bytes.
Label lengthEvery dot-separated label is at most 63 bytes and cannot be empty.
CharactersRFC-style profiles allow ASCII letters, digits, and hyphens; Kubernetes profiles allow lowercase letters, digits, and hyphens.
Label edgesEvery label starts and ends with an alphanumeric character.
Single-label profilesExactly one label is accepted; dotted input fails.
Kubernetes label profileThe single label must start with a lowercase letter.
Dotted numeric endingThe final label of a multi-label hostname cannot contain digits only.
IP addressA dotted-decimal IPv4 address is rejected as a hostname.
Organization regexThe selected expression must match either the first label or full hostname; JavaScript global and sticky flags are removed before matching.
Lowercase policyUppercase is Fail, Review, or ignored for non-Kubernetes profiles; it always fails a Kubernetes profile.
Duplicate policyA repeated normalized name becomes Review, Fail, or no finding according to the selected policy.

Rules are additive. A row can fail both syntax and organization policy, and the ledger preserves every applicable explanation. Remediation priorities place extraction, syntax, pattern, and suffix failures at P1; case and duplicate findings default to P2 unless the selected duplicate policy makes them blocking.

Privacy Notes:

Inventory text, naming expressions, and suffixes are processed in the current browser tab and are not added to shareable query state. No DNS request is made. Internal hostnames can still leave the browser when you copy, download, or share an exported ledger, so handle those artifacts according to your organization’s data policy.

Worked Examples:

Policy drift in a valid hostname

DC02-FW-EDGE-01.example.internal can satisfy RFC-style label syntax because ASCII uppercase letters are allowed there, yet it fails when Lowercase policy is Require. Under the equivalent Kubernetes profile, uppercase is blocking regardless of the separate case setting.

Host-label regex with a preserved suffix

With Regex target set to the first label, the organization expression checks dc01-rtr-edge-01 while .example.internal is assessed by hostname syntax and the optional suffix rule. Selecting the full hostname instead sends the complete dotted name to the same expression.

References: