Find the server behind an IP address

An abuse report, a firewall log or a DNS answer often names nothing but an IP address. Cloud Viewer finds the resource that has or contains that address, across all your projects, so you know which machine to look at before you do anything else.

This works in free mode too. The search runs on your device, so it also covers projects that Cloud Viewer’s servers have never seen.

Search for the address

1. Open the Resources tab and remove any project filter, so every project is searched. On iPhone, also choose All at the top.
2. Type the full address into Search resources or IP address, for example 203.0.113.7 or 2001:db8:3::1.
3. Read the results. Under each name, a line says what matched: IPv4 · 203.0.113.7, IPv6 · 2001:db8:3::1/64 or Subnet · 10.0.1.0/24.

On iPhone and Android, the link cloudviewer://resources?q=203.0.113.7 opens the same search with the address filled in, for example from a runbook.

What matches

• The search covers server IPv4 and IPv6 addresses, primary IPs, floating IPs, load balancer IPv4 addresses, and the ranges and subnets of private networks.
• A server’s IPv6 address is stored as a /64, and the search checks whether the address falls inside it. A single host address from that block finds the server it belongs to.
• More than one result is normal. A server and its primary IP carry the same address.
• Only whole addresses are matched. 192.0.2 is treated as text, and CIDR ranges are not accepted as input. An IPv4 address written in IPv6 form (::ffff:192.0.2.5) is searched as the IPv4 address.
• Firewall rules are not searched. A rule that mentions an address answers a different question than which machine carries it.
• Dedicated servers are not in the Hetzner Cloud API, so their addresses are not searched.

No result means the address is in none of the projects Cloud Viewer can see.

Or ask Claude

With the Claude connector on Pro or Team, ask Claude something like “Which of my servers has 203.0.113.7?”. Its tool find_resource_by_ip searches every connected project with the same rules and says which field matched. It does not see projects that are only on your device.

Then

• Tap the result, then Open details: its status, recent activity, alerts and log lines show what the machine has been doing (Resources and details).
• To pass it on, use Share brief, or Copy for coding agent for an agent that will investigate (Hand off to a coding agent).
• Cloud Viewer only reads. To act, for example to shut the server down or change its firewall, open the Hetzner Console.