What it does
Paste the output of the F5 iqdump command, lines from /var/log/gtm, or the name of a topic, and this explains F5's iQuery protocol without touching a device. iQuery is the proprietary, XML-based protocol that BIG-IP DNS (formerly GTM) uses to talk to the big3d agent on itself and on every other BIG-IP it knows about. The tool decodes what you paste and explains the architecture behind it. It is a decode-and-explain tool that runs entirely in your browser, grounded in F5's own BIG-IP DNS/GTM documentation.
Decoding iqdump output
iqdump streams the live iQuery data between two systems so you can verify the path and the SSL authentication. Paste its output and the tool reads back the header comment lines, the local hostname you ran it from, the big3d peer it connected to and the port (4353), the synchronization group it subscribed to, and the timestamp, then the <xml_connection> stanza fields such as version, the big3d build string, and connection_id. Each field is explained, and a present big3d peer line is called out as evidence that the TCP path and SSL trust to that agent are working, because a broken path makes iqdump report an error instead.
Decoding /var/log/gtm lines
The gtmd process logs iQuery mesh health to /var/log/gtm. Paste those lines and the tool decodes the box state-change messages, for example a green --> red transition that means a BIG-IP became unavailable over iQuery, along with the SNMP_TRAP entries and the big3d connection established/lost messages. A green --> red transition is flagged with what to check next: the iQuery path (TCP 4353, SSL trust) to that box, and whether its big3d is running and version-compatible.
Explaining the architecture
Type or click a topic and the tool explains it in F5's terms: the iQuery mesh of long-lived connections, TCP port 4353, the SSL certificate-based trust that bigip_add, big3d_install, and gtm_add bootstrap, the iqdump command itself, what iQuery carries (object availability plus the load-balancing metrics dynamic GSLB needs), the gtmd and big3d agents, and the VLAN rule that iQuery is sent only on the VLAN on which a system receives it.
Scope and grounding
This explains and decodes; it never opens a socket, runs iqdump, or fetches anything, and the same input always produces the same output. It reads the shape of iqdump and log text rather than validating an entire iQuery exchange. Every fact comes from F5's BIG-IP DNS/GTM concepts and implementations manuals, the LTM-DNS operations guide, and the K-articles on iQuery trust and troubleshooting; the example is a real iqdump sample published by F5. Note that the Link Controller module was removed in BIG-IP 21.0.0. Nothing you paste leaves the page.