--- title: "Check Locations: Areas, Limits and Alert Rules | Uptrack" description: "The 27 Uptrack check locations in 12 areas, how many each plan can use, how often each city checks, and what must fail before you get an alert." url: https://uptrack.app/docs/check-locations ---

# Check locations

Uptrack has 27 check locations in 12 areas. Each area has two Cloudflare cities, and three areas also have a core probe. HTTP and keyword monitors can use all of them. Ping, port, DNS and SSL checks run only from the core probes in Ashburn, Nuremberg and Hyderabad. ## Areas | Area | Locations | | -------------------------- | -------------------------- | | North America East | Ashburn, Toronto, Montréal | | US Central | Dallas, Chicago | | North America West | Oregon, N. California | | Western Europe | London, Paris | | Central and Eastern Europe | Nuremberg, Warsaw, Milan | | South Asia | Hyderabad, Mumbai, Delhi | | Southeast Asia | Singapore, Jakarta | | East Asia | Tokyo, Seoul | | South America | São Paulo, Rio de Janeiro | | Oceania | Sydney, Melbourne | | Middle East | Doha, Tel Aviv | | Africa | Johannesburg, Cape Town | ## What each plan can use - Pro: any 6 areas, which is 12 to 15 locations. You pick them for each monitor. - Team and Business: all 12 areas, which is 27 locations. Each monitor keeps at least 2 areas, so a second area can confirm a failure. You can also run a monitor on Cloudflare cities only, with no core probe. ## How often each location checks The two cities of an area take turns, so the area checks your site at every interval and each city checks at every second interval. A core probe checks at every interval. ## What must fail before you get an alert - A location that fails checks again once before its failure counts. - An area fails when every location that answered in it failed. - Three picked areas must fail, or every picked area when you pick fewer than three. - The failures must continue for the number of checks in your confirmation setting, at least 2. - When a core probe in your picks answers and every such probe is up, city failures alone do not alert. A site that fails in only one or two areas is a regional problem. It shows on the monitor, and you can turn on a separate regional notice for each monitor. ## When a location cannot give an answer A location that cannot run a check, is blocked by your site or is throttled does not count as a failure. It counts as no answer. Each Cloudflare city also checks two control sites in every batch. When a city fails them both, its failures are ignored for that batch. This has a limit. A monitor with no core probe has no independent check on Cloudflare. A Cloudflare fault that passes the control sites and fails your site could send an alert. Keep at least one core area if you want that check. ## Allow Uptrack through your firewall City checks come from Cloudflare Workers, so they use addresses that Cloudflare shares with its other customers. To let them through, add a custom header with a long secret value to your monitor, and allow requests that carry it. City checks also carry the header `CF-Worker: uptrack.app`. It helps you find them in your logs. Do not use it as your only allow rule, because any client can send it to a site that Cloudflare does not protect. The bot details are on the [Uptrack bot page](https://uptrack.app/bot). ## Check from where your users are Plans start from $3/mo, with a 30-day money-back guarantee. [See plans](https://uptrack.app/pricing)