IPv6 Zone ID Parser¶

The Zone ID Parser is in the Tool Drawer on the IPv6 tab. Enter an IPv6 address with an optional zone identifier, and the parser returns the canonical address, the zone ID (if any), and whether the address is link-local.

What is a zone ID?¶

IPv6 zone identifiers (RFC 4007) scope an address to a specific network interface. They are written after a percent sign — e.g. fe80::1%eth0 — and are required to disambiguate link-local addresses on hosts with more than one interface, because the same fe80::/10 prefix exists independently on every link.

fe80::1%eth0   →  link-local address fe80::1, scoped to interface eth0
fe80::1%en0    →  same address, scoped to a different interface

The zone identifier is a host-local label (interface name on Linux/macOS, interface index on Windows) and is never transmitted on the wire.

Why only link-local?¶

Zone identifiers are only meaningful on link-local addresses (fe80::/10). Global unicast and ULA addresses are routable on their own and don't need an interface scope. Most operating systems silently ignore a zone identifier supplied with a non-link-local address — the parser raises a yellow warning band when this happens so you don't deploy configuration that is silently broken.

Examples¶

Input	Address	Zone ID	Link-local	Notes
`fe80::1%eth0`	`fe80::1`	`eth0`	Yes	Valid scoped link-local
`fe80::1`	`fe80::1`	—	Yes	Link-local, no zone
`2001:db8::1%eth0`	`2001:db8::1`	`eth0`	No	Warning: zone ignored
`2001:db8::1`	`2001:db8::1`	—	No	Plain global unicast
`fe80::1%`	—	—	—	Error: empty zone

Validation rules¶

Address must be a syntactically valid IPv6 address. The parser normalises every address through inet_pton/inet_ntop, so compressed and expanded forms canonicalise to the same output.
Zone identifier (if present) must be 1–32 characters and may contain only A–Z, a–z, 0–9, _, and -. Anything else raises an error.

Shareable URL¶

The parser supports the standard shareable-URL pattern. The percent sign in a zone identifier must be URL-encoded as %25:

/ipv6/zoneid?zoneid_input=fe80::1%25eth0

PHP decodes the %25 back to a literal % server-side, so the parser sees the original input.

REST API¶

`POST /api/v1/zone-id`¶

Request body:

{
  "input": "fe80::1%eth0"
}

Successful response (HTTP 200):

{
  "ok": true,
  "data": {
    "address":       "fe80::1",
    "zone_id":       "eth0",
    "is_link_local": true,
    "warning":       null
  }
}

Warning case (zone supplied on a non-link-local address) — HTTP 200, but warning is a non-null string explaining that most operating systems will ignore the zone:

{
  "ok": true,
  "data": {
    "address":       "2001:db8::1",
    "zone_id":       "eth0",
    "is_link_local": false,
    "warning":       "Zone identifiers are only meaningful on link-local (fe80::/10) addresses; the zone will be ignored by most operating systems."
  }
}

Error case (invalid address or malformed zone) — HTTP 400:

{
  "ok": false,
  "error": "Zone identifier must be 1–32 characters using letters, digits, \"_\" or \"-\"."
}

See the full API reference at POST /api/v1/zone-id.