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REx Commands

The rex command group queries the APNIC REx (Resource EXplorer) cross-RIR resource registry REST API at https://api.rex.apnic.net. REx aggregates delegated resources across all five RIRs (APNIC, ARIN, RIPE, LACNIC, AFRINIC) and attributes them to resource-holder organisations via opaque identifiers — capabilities that go beyond the per-RIR stats and RDAP endpoints elsewhere in this CLI. All endpoints return JSON and require no authentication.

Source: cmd_rex.go.

Command Map

graph LR
    REX["rex"]

    REX --> NET["network<br/>locate caller's own network"]
    REX --> RES["resources [type]<br/>recently delegated resources"]
    REX --> HLD["holder &lt;opaqueId&gt; &lt;rir&gt;<br/>full inventory for one org"]
    REX --> CNT["count<br/>distinct holders across RIRs"]

    NET -.->|"no args"| FROM["source IP of caller"]
    RES -.->|"optional: ipv4|ipv6|asn"| FILTER["type filter"]
    HLD -.->|"rir: afrinic|apnic|arin|lacnic|ripencc"| NOTE["RIPE NCC code is ripencc"]

apnic rex network

Locate the caller's own network from the source IP of the request. Returns the covering prefix, the origin ASN, and the economy (country) — no parameters required. The server infers these from the TCP peer address.

apnic rex network
apnic --json rex network | jq '.prefix, .asn, .economy'

Output format (human-readable)

# rex user-network
ip  203.0.113.45
prefix  203.0.113.0/24
asn 13335
economy AU

apnic rex resources [type]

List a bounded, most-recent-first window of cross-RIR delegated resources with holder attribution. The optional positional argument filters by resource kind: ipv4, ipv6, or asn. Omit it to list all kinds. REx returns the most recently delegated resources, not the full historical list.

Positional Type Description
[type] string Optional filter: ipv4, ipv6, or asn. 
apnic rex resources
apnic rex resources asn
apnic --json rex resources ipv4 | jq '.items[0:10]'

Output format (human-readable)

# rex resources: 500 items
ipv4    203.0.113.0/24  ExampleCorp APNIC   AU  A92E1062
ipv6    2001:db8::/32   ExampleCorp APNIC   AU  A92E1062
asn 64512   ExampleCorp RIPE    NL  B7F30011
...

Columns are tab-separated: Type Resource HolderName RIR CC OpaqueID.

apnic rex holder <opaqueId> <rir>

Aggregate every ASN and prefix held by one organisation, given its opaque identifier and the responsible RIR. Returns the holder's full ASN and prefix inventory together with derived size metrics (/24 units for IPv4, /48 units for IPv6).

Positional Type Description
<opaqueId> string The holder's opaque identifier (obtainable from rex resources or from the extended delegated stats opaque-id column).
<rir> string Responsible RIR. Must be one of afrinic, apnic, arin, lacnic, ripencc.

Note: The RIPE NCC code is ripencc, not ripe. Passing ripe is rejected by the API.

# Full inventory for one APNIC holder
apnic rex holder A92E1062 apnic

# RIPE NCC holder
apnic rex holder B7F30011 ripencc

apnic --json rex holder A92E1062 apnic | jq '{asns: .asns, ipv4_24: .ipv4_24_count, ipv6_48: .ipv6_48_count}'

Output format (human-readable)

# rex holder: ExampleCorp (APNIC)
asns    3
asn 64512
asn 64513
asn 64514
ipv4    12 (/24 units: 256)
ipv4    203.0.113.0/24
ipv4    203.0.114.0/23
ipv6    4 (/48 units: 1024)
ipv6    2001:db8::/32
...

apnic rex count

Return the total number of distinct resource-holder organisations across all five RIRs.

apnic rex count
# # rex holders unique-count
# count 154328

apnic --json rex count | jq '.count'

Query Flow

sequenceDiagram
    participant U as User
    participant CLI as apnic rex
    participant SDK as apnic.Client
    participant REX as api.rex.apnic.net

    U->>CLI: apnic rex holder A92E1062 apnic
    CLI->>SDK: FetchRExHolder(ctx, "A92E1062", "apnic")
    SDK->>REX: GET /v1/holder/A92E1062?rir=apnic
    REX-->>SDK: holder JSON (asns, ipv4, ipv6, metrics)
    SDK-->>CLI: *RExHolderResult
    CLI-->>U: human-readable / --json

rex network issues a parameterless GET and the server infers the caller's network from the source IP. rex resources appends an optional ?type= filter. rex count returns a single aggregated integer.

Global flags of note

Flag Effect on REx
--rex-base-url Override the REx API root (api.rex.apnic.net).
--rate-limit / --stealth REx is a public API with no documented hard rate limit, but polite throttling is recommended for batch loops.
--cache-ttl Caches GET responses by URL; useful when iterating over many opaque IDs in a script.
--json Emit the verbatim SDK struct.

Output summary

Subcommand Human-readable --json
rex network # rex user-network then ip/prefix/asn/economy rows RExUserNetwork
rex resources [type] # rex resources: N items then Type<Tab>Resource<Tab>HolderName<Tab>RIR<Tab>CC<Tab>OpaqueID rows RExResourcesResult
rex holder <opaqueId> <rir> header + counts + per-resource rows RExHolderResult
rex count # rex holders unique-count then count<Tab>N RExHoldersUniqueCount