Add health-check-cn.md

doc/README_CN.md

@@ -25,7 +25,7 @@ Reference document
 * [架构设计](architecture-design-cn.md)
 * [压力测试](benchmark-cn.md)
 * [如何构建 Apache APISIX](how-to-build-cn.md)
-* [健康检查](health-check.md): 支持对上游节点的主动和被动健康检查，在负载均衡时自动过滤掉不健康的节点。
+* [健康检查](health-check-cn.md): 支持对上游节点的主动和被动健康检查，在负载均衡时自动过滤掉不健康的节点。
 * Router(路由)
     * [radixtree](router-radixtree.md)
     * [r3](router-r3.md)

doc/health-check-cn.md

@@ -0,0 +1,103 @@
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+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
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+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
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+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+-->
+
+# [English](health-check.md)
+
+## Upstream的健康检查
+
+APISIX的健康检查使用[lua-resty-healthcheck](https://github.com/Kong/lua-resty-healthcheck)实现，你可以在upstream中使用它。
+
+下面是一个检查检查的例子：
+
+```shell
+curl http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
+{
+    "uri": "/index.html",
+    "plugins": {
+        "limit-count": {
+            "count": 2,
+            "time_window": 60,
+            "rejected_code": 503,
+            "key": "remote_addr"
+        }
+    },
+    "upstream": {
+         "nodes": {
+            "127.0.0.1:1980": 1,
+            "127.0.0.1:1970": 1
+        },
+        "type": "roundrobin",
+        "retries": 2,
+        "checks": {
+            "active": {
+                "http_path": "/status",
+                "host": "foo.com",
+                "healthy": {
+                    "interval": 2,
+                    "successes": 1
+                },
+                "unhealthy": {
+                    "interval": 1,
+                    "http_failures": 2
+                },
+                "req_headers": ["User-Agent: curl/7.29.0"]
+            },
+            "passive": {
+                "healthy": {
+                    "http_statuses": [200, 201],
+                    "successes": 3
+                },
+                "unhealthy": {
+                    "http_statuses": [500],
+                    "http_failures": 3,
+                    "tcp_failures": 3
+                }
+            }
+        }
+    }
+}'
+```
+
+监控检查的配置内容在`checks`中，`checks`包含两个类型：`active` 和 `passive`，详情如下
+
+* `active`: 要启动探活健康检查，需要在upstream配置中的 `checks.active` 添加如下配置项。
+
+    * `active.http_path`: 用于发现upstream节点健康可用的HTTP GET请求路径。
+    * `active.host`: 用于发现upstream节点健康可用的HTTP请求主机名。
+
+    `healthy`的阀值字段：
+    * `active.healthy.interval`: 健康的目标节点的健康检查间隔时间（以秒为单位），最小值为1。
+    * `active.healthy.successes`: 确定目标是否健康的成功次数，最小值为1。
+
+    `unhealthy`的阀值字段：
+    * `active.unhealthy.interval`: 针对不健康目标节点的健康检查之间的间隔（以秒为单位），最小值为1。
+    * `active.unhealthy.http_failures`: 确定目标节点不健康的http请求失败次数，最小值为1。
+    * `active.req_headers`: 其他请求标头。数组格式，可以填写多个标题。
+
+* `passive`: 要启用被动健康检查，需要在upstream配置中的 `checks.passive` 添加如下配置项。
+
+    `healthy`的阀值字段：
+    * `passive.healthy.http_statuses`: 如果当前HTTP响应状态码是其中任何一个，则将upstream节点设置为 `healthy` 状态。否则，请忽略此请求。
+    * `passive.healthy.successes`: 如果upstream节点被检测成功（由 `passive.healthy.http_statuses` 定义）的次数超过 `successes` 次，则将该节点设置为 `healthy` 状态。
+
+    `unhealthy`的阀值字段：
+    * `passive.unhealthy.http_statuses`: 如果当前HTTP响应状态码是其中任何一个，则将upstream节点设置为 `unhealthy` 状态。否则，请忽略此请求。
+    * `passive.unhealthy.tcp_failures`: 如果TCP通讯失败次数超过 `tcp_failures` 次，则将upstream节点设置为 `unhealthy` 状态。
+    * `passive.unhealthy.timeouts`: 如果被动健康检查超时次数超过 `timeouts` 次，则将upstream节点设置为 `unhealthy` 状态。
+    * `passive.unhealthy.http_failures`: 如果被动健康检查的HTTP请求失败（由 `passive.unhealthy.http_statuses` 定义）的次数超过 `http_failures`次，则将upstream节点设置为 `unhealthy` 状态。