What is Check-Host used for before a Slammed.st test?

Check-Host.net (and check-host.cc) checks host availability with multi-node ping, HTTP, DNS, and TCP/UDP port probes so you confirm a verified target is reachable before spending Hub capacity.

Can Censys help find a backend or origin IP?

On infrastructure you own or are authorized to assess, Censys Search can inventory exposed hosts and services and surface clues for the origin/backend behind a CDN. Unauthorized targeting is prohibited.

Is FOFA an alternative to Censys?

Yes. FOFA is a cyberspace asset search engine that teams use as a Censys-style alternative for authorized inventory of hosts, banners, and exposed services.

RESOURCES

Useful tools suggested by developers of Slammed.st

External diagnostics we use before authorized Hub runs: confirm reachability, map services you own, and spot origin / edge layout — never for targeting systems without permission.

Check-Host.net UI for ping, HTTP, DNS, TCP and UDP checks from multiple locations — Check-Host — multi-node host availability checks

Why these tools

Before a capacity window on infrastructure you own, you need more than a URL in Hub. Is the host reachable from multiple regions? Which services are exposed? What sits in front of the origin (CDN/WAF)? These public tools help answer that so your Slammed.st Layer 4 / Layer 7 run hits the right target class.

Authorized use only. Finding an origin IP to attack a third party is prohibited — see Acceptable Use and authorized load testing. Use these for systems you control or have written permission to assess.

Also useful: Concurrent vs RPS calculator · Glossary · in-app Learn (login).

Check-Host.net / Check-Host.cc

Check-Host.net (also check-host.cc) is an online tool for checking availability of websites, servers, hosts, and IP addresses. It also returns geolocation and WHOIS-style context from several IP databases.

IP Info — country, region, city, ZIP, timezone, ISP, organization, IP range.
Ping — reachability, latency, and packet loss from many world nodes.
HTTP — response status and availability from multiple countries / datacenters.
DNS — A / AAAA / PTR with TTL from nameservers worldwide (propagation checks).
TCP / UDP port — whether a specific port answers from external probes.
Subnet calculator — IP range ↔ CIDR conversions.
API — build custom monitoring around the same checks.

When to use with Slammed.st: smoke-check that your verified target is up from outside before you spend Hub concurrents; confirm DNS updates after a cutover; sanity-check open ports on staging.

Censys Search

search.censys.io indexes internet hosts and services. For authorized capacity work it is useful to inventory what your domain / ASN exposes and to hunt clues for the backend / origin IP when a CDN sits in front of an application you own.

Search by IP, hostname, protocol, or field queries.
Review open services and certificates tied to your assets.
Compare edge vs origin presentation before choosing L4 vs L7 Hub methods.

Only query and test assets you are allowed to assess. Pair findings with Hub Layer 7 or Layer 4 runs on verified targets — and with AI Target Analyzer inside the panel.

FOFA (Censys alternative)

FOFA dark search UI for cyberspace asset discovery — FOFA — cyberspace asset search

fofa.io is a cyberspace asset search engine — a practical alternative to Censys when you need another index or query syntax for the same authorized inventory job (hosts, banners, certificates, exposed panels).

Use it the same way: map assets you own, cross-check what Censys shows, and confirm you are not about to load-test the wrong IP behind a shared CDN edge.

Shodan

shodan.io searches internet-connected devices and exposed services. For Slammed.st workflows it helps you:

See which ports/services on your hosts are reachable from the public internet.
Spot forgotten panels, databases, or admin surfaces before a load window.
Cross-check origin-facing endpoints when CDN hides the application hostname.

Together with Check-Host (liveness) and Censys/FOFA (inventory), Shodan rounds out pre-flight recon for authorized tests. Then size the run with the RPS calculator and start in Hub.

Suggested workflow

Verify ownership / written permission for the target.
Check-Host: ping + HTTP + DNS from several nodes.
Censys / FOFA / Shodan: inventory services and origin clues for assets you own.
Confirm the exact IP/URL in Slammed.st target verification.
Run a short smoke test in Hub, then scale with abort criteria.

Start free · Developer docs · Pricing · Resources hub.

FAQ

What is Check-Host used for before a Slammed.st test?: Check-Host.net (and check-host.cc) checks host availability with multi-node ping, HTTP, DNS, and TCP/UDP port probes so you confirm a verified target is reachable before spending Hub capacity.
Can Censys help find a backend or origin IP?: On infrastructure you own or are authorized to assess, Censys Search can inventory exposed hosts and services and surface clues for the origin/backend behind a CDN. Unauthorized targeting is prohibited.
Is FOFA an alternative to Censys?: Yes. FOFA is a cyberspace asset search engine that teams use as a Censys-style alternative for authorized inventory of hosts, banners, and exposed services.

Resources hub · Glossary · Tools matrix · RPS calculator · Useful network tools · Blog · Pricing · Start free