Add Uptime Monitoring Documentation

docs/organization/early-adopter-features/index.mdx

@@ -20,3 +20,4 @@ Limitations:
 - [Issue Status](/product/issues/states-triage/) tags
 - [Span Summary](/product/performance/transaction-summary/#span-summary)
 - [Investigation Mode](/product/performance/retention-priorities/#investigation-mode) for retention priorities in Tracing
+- [Uptime Monitoring](/product/alerts/uptime-monitoring/)

docs/product/alerts/index.mdx

@@ -36,6 +36,12 @@ Create alerts to monitor metrics, such as:
 
 You can find a full list of available metric alerts in [Metric Alerts](/product/alerts/alert-types/#metric-alerts).
 
+## Uptime Monitoring Alerts
+
+[Uptime alerts](/product/alerts/uptime-monitoring/) are triggered when an uptime HTTP check request fails to meet our
+[uptime check criteria](/product/alerts/uptime-monitoring/#uptime-check-criteria).
+You can use uptime alerts to make sure a specific URL is constantly available, even during periods of low or no traffic.
+
 ## Creating Alerts
 
 When you create a new project in [sentry.io](https://sentry.io), you can select a default issue alert. However, you can also [create your own alerts](/product/alerts/create-alerts/) to suit your team’s needs, using these [best practices](/product/alerts/best-practices/) as a guide.

docs/product/alerts/uptime-monitoring/automatic-detection.mdx

@@ -0,0 +1,36 @@
+---
+title: Automatic Detection
+sidebar_order: 51
+description: "Learn how automatic detection of uptime monitoring works."
+---
+
+<Include name="feature-stage-alpha-uptime.mdx" />
+
+The automatic detection of uptime alerts sets up uptime alerts for the most frequently encountered
+hostnames in all URLs of your error data. This helps ensure that critical hostnames are continuously monitored,
+enhancing the reliability and availability of your web services.
+
+## How It Works
+
+We analyze all the URLs detected in your project's captured error data to find the hostname that appears most frequently. We then create an uptime alert if it passes our [uptime check criteria](/product/alerts/uptime-monitoring/#uptime-check-criteria).
+
+To avoid creating flaky alerts, the hostname undergoes an "onboarding period" of three days. During this period, we send HTTP requests to the hostname every hour. If the request fails at least three times, the hostname is dropped and re-evaluated after seven days.
+
+<Alert level="info">
+Sentry will execute uptime checks against the hostname root path of the most frequently seen URLs. For example, if the most seen URL in your events is `GET https://www.example.com/docs/introduction` the check will be `GET https://www.example.com/`.
+</Alert>
+
+## Disabling Automatic Detection
+Deleting an alert will disable automatic detection for the entire project linked to the host. This feature can also be turned off globally for the entire organization from the [organization settings](https://sentry.io/orgredirect/organizations/:orgslug/settings/organization) page.
+
+Alternatively, the hostname's `robots.txt` can be updated to disallow Sentry:
+
+```txt{tabTitle: Example}{filename: robots.txt}
+User-agent: SentryUptimeBot
+Disallow: *
+```
+
+## Current Limitations
+
+In the current version, automatically-detected uptime alerts can only be deleted, not edited. Support for editing
+will be added in the future. Additionally, each organization is limited to one automatically-detected host.

docs/product/alerts/uptime-monitoring/index.mdx

@@ -0,0 +1,39 @@
+---
+title: Uptime Monitoring
+sidebar_order: 50
+description: "Learn how to help maintain uptime for your web services by monitoring relevant URLs with Sentry's Uptime Monitoring."
+---
+
+<Include name="feature-stage-alpha-uptime.mdx" />
+
+Sentry's Uptime Monitoring lets you monitor the availability and reliability of your web services effortlessly.
+In the current version, uptime is [automatically configured](/product/alerts/uptime-monitoring/automatic-detection/) as a new alert for only the most relevant URL detected in your organization. In future updates, you'll have the flexibility to add and monitor additional URLs.
+
+## Uptime Check Criteria
+
+Our uptime monitoring system verifies the availability of your URLs
+by performing GET requests at regular 5-minute intervals.
+For a URL to be considered up and running, the response must meet the following criteria:
+
+1. **Successful Response (2xx Status Codes):**
+The URL must return an HTTP status code in the 200–299 range, indicating a successful request.
+2. **Automatic Handling of Redirects (3xx Status Codes):** Sentry will follow redirects for URLs returning an HTTP status code in the 300–399 range and verify that the final destination URL returns a successful response. This ensures that redirects won't falsely trigger downtime alerts.
+3. **Timeout Setting:** Each request has a timeout threshold of 10 seconds.
+If the server doesn't respond within this period, the check will be marked as a failure,
+indicating a potential downtime or performance issues.
+4. **DNS Issue Detection:** Our monitoring also includes the detection of DNS resolution issues.
+If a DNS issue is detected, the check will be marked as a failure,
+allowing you to address the underlying connectivity problems.
+
+## Notifications
+
+An uptime alert continuously monitors the configured URL with the criteria defined above. If a failure is detected,
+a new [uptime issue](/product/issues/issue-details/uptime-issues/) with failed check and related errors details will be created.
+
+To start getting notifications for a new downtime issue, [configure an issue alert](/product/alerts/create-alerts/issue-alert-config/) and choose the issue category "uptime". Then choose how you'd like to be notified (via email, Slack, and so on).
+
+![Uptime issue alert rule configuration](./img/uptime-issue-alert-rule.png)
+
+## Learn More About Uptime Monitoring
+
+<PageGrid />

docs/product/alerts/uptime-monitoring/troubleshooting.mdx

@@ -0,0 +1,33 @@
+---
+title: Troubleshooting
+sidebar_order: 52
+description: "Learn how to troubleshoot potential Uptime Monitoring problems."
+---
+
+<Include name="feature-stage-alpha-uptime.mdx" />
+
+## Verify Feature Eligibility
+
+Uptime alerts are only available for organizations that have early adopter features enabled. They must also have URLs that match our [auto detection criteria](/product/alerts/uptime-monitoring/automatic-detection/#how-it-works). In the current version, organizations are limited to a single uptime alert.
+
+## Verify Firewall Configuration
+
+Some hosting platforms can block incoming requests from Sentry's Uptime Bot, falsely triggering uptime alerts. We recommend verifying your firewall configuration to ensure incoming requests from Sentry are allowed.
+
+If you need to configure your firewall allowlist to include Sentry's Uptime Bot, we recommend checking against our `User-Agent`, given that our IP addresses can change without notice.
+
+### User Agent
+
+Our uptime check requests use the following `User-Agent`:
+
+```
+Mozilla/5.0 (compatible; SentryUptimeBot/1.0; +http://docs.sentry.io/product/alerts/uptime-monitoring/)
+```
+
+### IP Addresses
+
+See [IP Ranges](/security-legal-pii/security/ip-ranges/#uptime-monitoring) for a complete list of IP addresses used for uptime checks.
+
+## Verify That Issue Alerts Match Downtime Issues
+
+Uptime alerts create downtime issues. If you're not receiving notifications when downtimes are detected, make sure you've properly [configured an issue alert](/product/alerts/create-alerts/issue-alert-config/) with the issue category "uptime".

docs/product/issues/issue-details/uptime-issues/index.mdx

@@ -0,0 +1,22 @@
+---
+title: Uptime Issues
+sidebar_order: 40
+description: "Learn how to use the information on the Issue Details page to debug an error issue."
+---
+
+<Include name="feature-stage-alpha-uptime.mdx" />
+
+An uptime issue is a grouping of detected downtime events for a specific URL. A downtime event is generated by
+active uptime alerts when HTTP requests fail to meet our
+[uptime check criteria](/product/alerts/uptime-monitoring/#uptime-check-criteria).
+
+![Uptime issue details](./img/uptime-issue-details.png)
+
+## Traced Errors
+
+Uptime checks made against web services configured with one of Sentry's supported SDKs contain a
+[trace](/concepts/key-terms/tracing/) that can be used to track detected errors resulting from failed HTTP uptime checks. The trace navigator allows you to browse through potential root causes of your downtime and is a powerful  tool for quickly identifying and resolving issues.
+
+## Issue Lifecycle
+
+Uptime issues are grouped by the monitored URL and created upon the first detected downtime. Sentry automatically resolves an ongoing uptime issue when the monitored URL returns to a healthy status and meets our [uptime check criteria](/product/alerts/uptime-monitoring/#uptime-check-criteria). If the URL experiences subsequent downtime, the issue's status will change to regressed.

docs/security-legal-pii/security/ip-ranges.mdx

@@ -122,3 +122,19 @@ All email is delivered from [SendGrid](https://sendgrid.com/) from the following
 ```
 
 These IP addresses are only for Sentry use.
+
+## Uptime Monitoring
+
+Sentry uses the following IP addresses for uptime checks:
+
+US
+```
+34.123.33.225
+34.41.121.171
+```
+
+EU
+```
+34.159.197.47
+35.242.231.10
+```

includes/feature-stage-alpha-uptime.mdx

@@ -0,0 +1,3 @@
+<Note>
+  This feature is only available if your organization has enabled [early adopter features](/organization/early-adopter-features/). Early adopter features are still in-progress and may have bugs. We recognize the irony. If you’re interested in participating, enable early adopter features in [organization settings](https://sentry.io/orgredirect/organizations/:orgslug/settings/organization).
+</Note>