Every scan runs through an entry host — the host the engine connects through to reach the target subnets (see Reaching non-routable subnets). To let a deep scan identify what it finds, store credentials for the hosts you expect to discover first — see Credentials.
Starting a scan
Go to Command Center → Discovery and start a new scan. A scan takes these inputs:- Entry host (required) — every scan starts from an entry host; the engine reaches the target subnets through it. To tunnel through it as a bastion, give its SSH user and key/secret credentials; leave both empty to run the scanner directly from the engine host. If the host has both a public and private IP, you also choose which one to dial.
- Scope (required) — one or more CIDRs to cover (e.g.
10.0.1.0/24, or a comma-separated list). A CIDR must be/16or narrower; broader ranges are rejected to keep a single scan bounded. - Credential allowlist (optional) — restricts which stored credentials a deep scan may try against discovered hosts. Leave it empty and all of the org’s credentials are eligible; narrow it to specific credentials when you want tight control over which logins are ever attempted, such as on sensitive or fragile network segments.
Scan depth
1
Scan
A reachability sweep only — 2501 checks which addresses in the range are live and which ports they have open. Nothing is logged into.
2
Deep scan
Everything in Scan, plus authenticated recon: 2501 attempts to log into each responding host with the eligible stored credentials and characterizes it (OS, services, routes, and technology stack). Deep scan is what populates a host’s tags.
Review mode
Choose how much of the scan runs without you in the loop:- Auto — recon starts automatically and every host that responds is promoted to a managed host. No manual step.
- Semi-auto — recon starts automatically, but you confirm each host before it’s created or updated.
- Manual — nothing fires on its own. You trigger recon and host creation yourself, node by node.
How it works
1
The scan runs in an ephemeral container
The scanner runs inside a short-lived container, one per subnet. It probes each address in the range, then — on a deep scan — attempts to authenticate to responding hosts using the eligible stored credentials.
2
Discovered nodes are characterized
Hosts that accept a connection are characterized automatically — OS, services, routes, and technology stack are derived and attached as tags.
3
Review the results
Discovered nodes appear in the infrastructure map as a review panel. For each node you can:
- Confirm — promote it to a managed host with all derived tags applied, making it immediately available for agent assignment.
- Ignore — dismiss the node without adding it to inventory.
Credentials and characterization
On a deep scan, 2501 tries the eligible stored credentials against each responding host to identify it. Credential handling is deliberately conservative:- 2501 only ever tries credentials already stored in the org — it never generates or guesses logins. The credential allowlist narrows this further; an empty allowlist makes every org credential eligible.
- A node is marked characterized only when a command actually proves access — not on a hopeful match.
- To protect accounts, 2501 stops using a credential after a configurable number of failed authentication attempts (max failures per credential).
- A host that responds but that no credential can authenticate to is still recorded as discovered, so you can supply a credential and re-run recon on it later.

