--- title: Manage monitors description: Learn how to set up and maintain monitors for your load balancer. image: https://developers.cloudflare.com/core-services-preview.png --- > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/load-balancing/llms.txt > Use this file to discover all available pages before exploring further. [Skip to content](#%5Ftop) # Manage monitors A monitor issues health monitor requests at regular intervals to evaluate the health of each endpoint within a [pool](https://developers.cloudflare.com/load-balancing/pools/). When a pool [becomes unhealthy](https://developers.cloudflare.com/load-balancing/understand-basics/health-details/), your load balancer takes that pool out of the endpoint rotation. For more details about monitors, refer to [Monitors](https://developers.cloudflare.com/load-balancing/monitors/). --- ## Create a monitor * [ Dashboard ](#tab-panel-7004) * [ API ](#tab-panel-7005) **Set up the monitor** You can create a monitor within the [load balancer workflow](https://developers.cloudflare.com/load-balancing/load-balancers/create-load-balancer/) or in the **Monitors** tab: 1. Go to **Load Balancing**. 2. Select the **Monitors** tab. 3. Select **Create monitor**. 4. Add the following information: * **Type**: The protocol to use for health monitors * _Non-enterprise customers_: Choose **HTTP**, **HTTPS**, or **TCP**. * _Enterprise customers_: Choose **HTTP**, **HTTPS**, **TCP**, **UDP ICMP**, **ICMP Ping**, or **SMTP**. * **Path**: The endpoint path to run health monitor requests against * **Port**: The destination port for health monitors 5. For additional settings, select **Advanced health monitor settings**: * **Interval**: * By increasing the default, you can improve failover time, but you may also increase load on your endpoints. * Minimum time in seconds is 60 (Pro), 15 (Business), and 10 (Enterprise). * **Timeout** and **Retries**: * The health monitor request will return unhealthy if it exceeds the duration specified in **Timeout** (and exceeds this duration more times than the specified number of **Retries**). * **Expected Code(s)**: The expected HTTP response codes listed individually (`200`, `302`) or as a range (for example, entering `2xx` would cover all response codes in the `200` range). * **Response Body**: * Looks for a case-insensitive substring in the response body. * Make sure that the value is relatively static and within the first 10 KB of the HTML page. * **Simulate Zone**: * It is recommended to use the same zone in which the Load Balancer exists. * Changes the egress zone settings of a health monitor request to ensure compatibility with features like [authenticated origin pulls](https://developers.cloudflare.com/ssl/origin-configuration/authenticated-origin-pull/), [Argo Smart Routing](https://developers.cloudflare.com/argo-smart-routing/), and [Dedicated CDN Egress IPs](https://developers.cloudflare.com/smart-shield/configuration/dedicated-egress-ips/). * **Follow Redirects**: * Instead of reporting a `301` or `302` code as unhealthy, the health monitor request follows redirects to the final endpoint. * **Configure Request Header(s)**: * Useful if your endpoints are expecting specific incoming headers. * **Header**: * The HTTP request headers to send in the health monitor. It is recommended that you set a Host header by default. The User-Agent header cannot be overridden. This parameter is only valid for HTTP and HTTPS monitors. 6. Select **Save**. Note To increase confidence in pool status, you can also increase the `consecutive_up` and `consecutive_down` fields when [creating a monitor with the API](https://developers.cloudflare.com/api/resources/load%5Fbalancers/subresources/monitors/methods/create/). To become healthy or unhealthy, monitored endpoints must pass this health monitor request the consecutive number of times specified in these parameters. **Prepare your servers** Make sure that your firewall or web server does not block or rate limit your configured health monitors or requests associated with [Cloudflare IP addresses ↗](https://www.cloudflare.com/ips). Each health monitor has the HTTP user-agent of `"Mozilla/5.0 (compatible; Cloudflare-Traffic-Manager/1.0; +https://www.cloudflare.com/traffic-manager/; pool-id: $poolid)"`, where the `$poolid` is the first 16 characters of the [associated pool](https://developers.cloudflare.com/load-balancing/pools/). Warning If you know that your endpoint is healthy but Load Balancing is reporting it as unhealthy, refer to our [Monitor troubleshooting guide](https://developers.cloudflare.com/load-balancing/troubleshooting/load-balancing-faq/#why-is-my-endpoint-or-pool-considered-unhealthy). **Attach the monitor to a pool** Once your monitor is created, you need to attach it to a pool: 1. Go to **Load Balancing**. 2. Select the **Pools** tab. 3. On a specific pool, select **Edit**. 4. Update the following information: * **Monitor**: Select your monitor. * **Health Monitor Regions:** Specifies geographic regions from which Cloudflare should send health monitor requests. Because of [how monitors check pool health](https://developers.cloudflare.com/load-balancing/monitors/#health-monitor-regions), selecting multiple regions could increase the load on your servers. * **Notification E-mail:** Contains email addresses that receive notifications (individual, mailing list address, PagerDuty address). 5. Select **Save**. The status of your health monitor will be _unknown_ until the results of the first check are available. **Set up the monitor** For a full list of monitor properties, refer to [Create Monitor](https://developers.cloudflare.com/api/resources/load%5Fbalancers/subresources/monitors/methods/create/). If you need help with API authentication, refer to [Cloudflare API documentation](https://developers.cloudflare.com/fundamentals/api/). Required API token permissions At least one of the following [token permissions](https://developers.cloudflare.com/fundamentals/api/reference/permissions/)is required: * `Load Balancing: Monitors and Pools Write` Create Monitor ``` curl "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/load_balancers/monitors" \ --request POST \ --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \ --json '{ "type": "https", "description": "Login page monitor", "method": "GET", "path": "/health", "header": { "Host": [ "example.com" ], "X-App-ID": [ "abc123" ] }, "port": 8080, "timeout": 3, "retries": 0, "interval": 90, "expected_body": "alive", "expected_codes": "2xx", "follow_redirects": true, "allow_insecure": true, "consecutive_up": 3, "consecutive_down": 2, "probe_zone": "example.com" }' ``` The response contains the complete definition of the new monitor. Response ``` { "success": true, "errors": [], "messages": [], "result": { "id": ":monitor-id", "created_on": "2021-01-01T05:20:00.12345Z", "modified_on": "2021-01-01T05:20:00.12345Z", "type": "https", "description": "Login page monitor", "method": "GET", "path": "/health", "header": { "Host": [ "example.com" ], "X-App-ID": [ "abc123" ] }, "port": 8080, "timeout": 3, "retries": 0, "interval": 90, "expected_body": "alive", "expected_codes": "2xx", "follow_redirects": true, "allow_insecure": true, "consecutive_up": 3, "consecutive_down": 2, "probe_zone": "example.com" } } ``` **Prepare your servers** Make sure that your firewall or web server does not block or rate limit your configured health monitors or requests associated with [Cloudflare IP addresses ↗](https://www.cloudflare.com/ips). Each health monitor has the HTTP user-agent of `"Mozilla/5.0 (compatible; Cloudflare-Traffic-Manager/1.0; +https://www.cloudflare.com/traffic-manager/; pool-id: $poolid)"`, where the `$poolid` is the first 16 characters of the [associated pool](https://developers.cloudflare.com/load-balancing/pools/). Warning If you know that your endpoint is healthy but Load Balancing is reporting it as unhealthy, refer to our [Monitor troubleshooting guide](https://developers.cloudflare.com/load-balancing/troubleshooting/load-balancing-faq/#why-is-my-endpoint-or-pool-considered-unhealthy). **Attach the monitor to a pool** Once your monitor is created, save its `id` property. Include this value in the `monitor` parameter when [creating your pool](https://developers.cloudflare.com/load-balancing/pools/create-pool/#create-a-pool). --- ## Edit a monitor * [ Dashboard ](#tab-panel-7000) * [ API ](#tab-panel-7001) To edit a monitor in the dashboard: 1. Go to **Load Balancing**. 2. Select **Monitors**. 3. On a specific monitor, select **Edit**. 4. Update settings as needed. 5. Select **Save**. When you edit a monitor with the API, your request type depends on how much you want to edit. To update specific settings without having to resubmit the entire configuration, use a [PATCH](https://developers.cloudflare.com/api/resources/load%5Fbalancers/subresources/monitors/methods/edit/) request. For broader changes, use a [PUT](https://developers.cloudflare.com/api/resources/load%5Fbalancers/subresources/monitors/methods/update/) request. --- ## Delete a monitor * [ Dashboard ](#tab-panel-7002) * [ API ](#tab-panel-7003) To delete a monitor in the dashboard: 1. Go to **Load Balancing**. 2. Select the **Monitors** tab. 3. On a specific monitor, select **Delete**. To delete a monitor using the API, send a [DELETE](https://developers.cloudflare.com/api/resources/load%5Fbalancers/subresources/monitors/methods/delete/) request. ```json {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/load-balancing/","name":"Load Balancing"}},{"@type":"ListItem","position":3,"item":{"@id":"/load-balancing/monitors/","name":"Monitors"}},{"@type":"ListItem","position":4,"item":{"@id":"/load-balancing/monitors/create-monitor/","name":"Manage monitors"}}]} ```