Watch every website and domain across your entire fleet from one place
Astra has two ways to check whether something is reachable. It helps to understand which one to use before you get started.
You set up a monitor once and every agent in your fleet runs it automatically. Think of it as a shared watch list — one entry, checked from every location.
Example: "Check that our company website is up and shows the word 'Welcome' — from every office, on every agent."
A service check is set up per agent for something that only that machine needs to reach. Other agents won't run it because it wouldn't make sense for them to.
Example: "Check that the RDP server on the 10.0.0.x network is reachable — but only from the agent at the New York office."
Quick rule of thumb: If you want all your agents to check something, use a Monitor. If only one specific agent should check it (because it's a local resource, an internal server, etc.), use a Service Check via that agent's settings.
A DNS Monitor watches whether a domain name resolves to the right address. Every agent performs this check and reports back, so you can see if the issue is network-wide or limited to specific locations.
This is especially useful for detecting DNS hijacking — when an ISP or a network device silently redirects your DNS lookups to a different address than expected.
Once created, every active agent in your organisation will begin running this check on its next cycle. No further setup is needed on each machine.
Click any DNS monitor in the list to open its results panel. You'll see a live feed of checks from all agents — the resolver used, the IP returned, the response time, and whether a hijack was detected. A green tick means everything looks correct; a red cross means the check failed or the IP didn't match.
An HTTP Monitor visits a URL and checks that it responds correctly. Every agent does this independently, so you can immediately see whether a problem is affecting everyone or just one location.
Unlike a simple ping, an HTTP Monitor can verify that a page is not just reachable but is actually returning the right content — useful for catching broken deployments, maintenance pages, or login redirects where the server is technically "up" but the service isn't working.
Click any HTTP monitor to see its results. Each row shows which agent ran the check, the status code returned, the response time, and whether your keyword was found. If an agent at a specific location is failing while others pass, the problem is likely local to that site's network rather than the server itself.
To change a monitor's settings — its URL, domain, interval, keyword, or anything else — click the pencil icon next to it in the list. This opens the same form used to create it, pre-filled with the current values. Save your changes and every agent will pick them up on their next check.
Use the toggle switch on each row to pause a monitor without deleting it. This is handy during planned maintenance when you know checks will fail. The bin icon in the results panel permanently removes the monitor and its history.
Use Service Checks (configured per-agent in Agent Settings) when:
Service Check results appear on each agent's detail page under the Services tab, not in the Monitors section.