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---
title: "taosAdapter"
description: "taosAdapter is a TDengine companion tool that acts as a bridge and adapter between TDengine clusters and applications. It provides an easy-to-use and efficient way to ingest data directly from data collection agent software such as Telegraf, StatsD, collectd, etc. It also provides an InfluxDB/OpenTSDB compatible data ingestion interface, allowing InfluxDB/OpenTSDB applications to be seamlessly ported to TDengine."
sidebar_label: "taosAdapter"
---

import Prometheus from "./_prometheus.mdx"
import CollectD from "./_collectd.mdx"
import StatsD from "./_statsd.mdx"
import Icinga2 from "./_icinga2.mdx"
import TCollector from "./_tcollector.mdx"

taosAdapter is a TDengine companion tool that acts as a bridge and adapter between TDengine clusters and applications. It provides an easy-to-use and efficient way to ingest data directly from data collection agent software such as Telegraf, StatsD, collectd, etc. It also provides an InfluxDB/OpenTSDB compatible data ingestion interface that allows InfluxDB/OpenTSDB applications to be seamlessly ported to TDengine.

taosAdapter provides the following features.

- RESTful interface
- InfluxDB v1 compliant write interface
- OpenTSDB JSON and telnet format writes compatible
- Seamless connection to Telegraf
- Seamless connection to collectd
- Seamless connection to StatsD
- Supports Prometheus remote_read and remote_write

## taosAdapter architecture diagram

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![TDengine Database taosAdapter Architecture](taosAdapter-architecture.webp)
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## taosAdapter Deployment Method

### Install taosAdapter

taosAdapter has been part of TDengine server software since TDengine v2.4.0.0. If you use the TDengine server, you don't need additional steps to install taosAdapter. You can download taosAdapter from [TAOSData official website](https://taosdata.com/en/all-downloads/) to download the TDengine server installation package (taosAdapter is included in v2.4.0.0 and later version). If you need to deploy taosAdapter separately on another server other than the TDengine server, you should install the full TDengine on that server to install taosAdapter. If you need to build taosAdapter from source code, you can refer to the [Building taosAdapter]( https://github.com/taosdata/taosadapter/blob/develop/BUILD.md) documentation.

### start/stop taosAdapter

On Linux systems, the taosAdapter service is managed by `systemd` by default. You can use the command `systemctl start taosadapter` to start the taosAdapter service and use the command `systemctl stop taosadapter` to stop the taosAdapter service.

### Remove taosAdapter

Use the command `rmtaos` to remove the TDengine server software if you use tar.gz package or use package management command like rpm or apt to remove the TDengine server, including taosAdapter.

### Upgrade taosAdapter

taosAdapter and TDengine server need to use the same version. Please upgrade the taosAdapter by upgrading the TDengine server.
You need to upgrade the taosAdapter deployed separately from TDengine server by upgrading the TDengine server on the deployed server.

## taosAdapter parameter list

taosAdapter is configurable via command-line arguments, environment variables and configuration files. The default configuration file is /etc/taos/taosadapter.toml on Linux.

Command-line arguments take precedence over environment variables over configuration files. The command-line usage is arg=val, e.g., taosadapter -p=30000 --debug=true. The detailed list is as follows:

```shell
Usage of taosAdapter:
      --collectd.db string                           collectd db name. Env "TAOS_ADAPTER_COLLECTD_DB" (default "collectd")
      --collectd.enable                              enable collectd. Env "TAOS_ADAPTER_COLLECTD_ENABLE" (default true)
      --collectd.password string                     collectd password. Env "TAOS_ADAPTER_COLLECTD_PASSWORD" (default "taosdata")
      --collectd.port int                            collectd server port. Env "TAOS_ADAPTER_COLLECTD_PORT" (default 6045)
      --collectd.user string                         collectd user. Env "TAOS_ADAPTER_COLLECTD_USER" (default "root")
      --collectd.worker int                          collectd write worker. Env "TAOS_ADAPTER_COLLECTD_WORKER" (default 10)
  -c, --config string                                config path default /etc/taos/taosadapter.toml
      --cors.allowAllOrigins                         cors allow all origins. Env "TAOS_ADAPTER_CORS_ALLOW_ALL_ORIGINS" (default true)
      --cors.allowCredentials                        cors allow credentials. Env "TAOS_ADAPTER_CORS_ALLOW_Credentials"
      --cors.allowHeaders stringArray                cors allow HEADERS. Env "TAOS_ADAPTER_ALLOW_HEADERS"
      --cors.allowOrigins stringArray                cors allow origins. Env "TAOS_ADAPTER_ALLOW_ORIGINS"
      --cors.allowWebSockets                         cors allow WebSockets. Env "TAOS_ADAPTER_CORS_ALLOW_WebSockets"
      --cors.exposeHeaders stringArray               cors expose headers. Env "TAOS_ADAPTER_Expose_Headers"
      --debug                                        enable debug mode. Env "TAOS_ADAPTER_DEBUG"
      --help                                         Print this help message and exit
      --influxdb.enable                              enable influxdb. Env "TAOS_ADAPTER_INFLUXDB_ENABLE" (default true)
      --log.path string                              log path. Env "TAOS_ADAPTER_LOG_PATH" (default "/var/log/taos")
      --log.rotationCount uint                       log rotation count. Env "TAOS_ADAPTER_LOG_ROTATION_COUNT" (default 30)
      --log.rotationSize string                      log rotation size(KB MB GB), must be a positive integer. Env "TAOS_ADAPTER_LOG_ROTATION_SIZE" (default "1GB")
      --log.rotationTime duration                    log rotation time. Env "TAOS_ADAPTER_LOG_ROTATION_TIME" (default 24h0m0s)
      --logLevel string                              log level (panic fatal error warn warning info debug trace). Env "TAOS_ADAPTER_LOG_LEVEL" (default "info")
      --monitor.collectDuration duration             Set monitor duration. Env "TAOS_MONITOR_COLLECT_DURATION" (default 3s)
      --monitor.identity string                      The identity of the current instance, or 'hostname:port' if it is empty. Env "TAOS_MONITOR_IDENTITY"
      --monitor.incgroup                             Whether running in cgroup. Env "TAOS_MONITOR_INCGROUP"
      --monitor.password string                      TDengine password. Env "TAOS_MONITOR_PASSWORD" (default "taosdata")
      --monitor.pauseAllMemoryThreshold float        Memory percentage threshold for pause all. Env "TAOS_MONITOR_PAUSE_ALL_MEMORY_THRESHOLD" (default 80)
      --monitor.pauseQueryMemoryThreshold float      Memory percentage threshold for pause query. Env "TAOS_MONITOR_PAUSE_QUERY_MEMORY_THRESHOLD" (default 70)
      --monitor.user string                          TDengine user. Env "TAOS_MONITOR_USER" (default "root")
      --monitor.writeInterval duration               Set write to TDengine interval. Env "TAOS_MONITOR_WRITE_INTERVAL" (default 30s)
      --monitor.writeToTD                            Whether write metrics to TDengine. Env "TAOS_MONITOR_WRITE_TO_TD" (default true)
      --node_exporter.caCertFile string              node_exporter ca cert file path. Env "TAOS_ADAPTER_NODE_EXPORTER_CA_CERT_FILE"
      --node_exporter.certFile string                node_exporter cert file path. Env "TAOS_ADAPTER_NODE_EXPORTER_CERT_FILE"
      --node_exporter.db string                      node_exporter db name. Env "TAOS_ADAPTER_NODE_EXPORTER_DB" (default "node_exporter")
      --node_exporter.enable                         enable node_exporter. Env "TAOS_ADAPTER_NODE_EXPORTER_ENABLE"
      --node_exporter.gatherDuration duration        node_exporter gather duration. Env "TAOS_ADAPTER_NODE_EXPORTER_GATHER_DURATION" (default 5s)
      --node_exporter.httpBearerTokenString string   node_exporter http bearer token. Env "TAOS_ADAPTER_NODE_EXPORTER_HTTP_BEARER_TOKEN_STRING"
      --node_exporter.httpPassword string            node_exporter http password. Env "TAOS_ADAPTER_NODE_EXPORTER_HTTP_PASSWORD"
      --node_exporter.httpUsername string            node_exporter http username. Env "TAOS_ADAPTER_NODE_EXPORTER_HTTP_USERNAME"
      --node_exporter.insecureSkipVerify             node_exporter skip ssl check. Env "TAOS_ADAPTER_NODE_EXPORTER_INSECURE_SKIP_VERIFY" (default true)
      --node_exporter.keyFile string                 node_exporter cert key file path. Env "TAOS_ADAPTER_NODE_EXPORTER_KEY_FILE"
      --node_exporter.password string                node_exporter password. Env "TAOS_ADAPTER_NODE_EXPORTER_PASSWORD" (default "taosdata")
      --node_exporter.responseTimeout duration       node_exporter response timeout. Env "TAOS_ADAPTER_NODE_EXPORTER_RESPONSE_TIMEOUT" (default 5s)
      --node_exporter.urls strings                   node_exporter urls. Env "TAOS_ADAPTER_NODE_EXPORTER_URLS" (default [http://localhost:9100])
      --node_exporter.user string                    node_exporter user. Env "TAOS_ADAPTER_NODE_EXPORTER_USER" (default "root")
      --opentsdb.enable                              enable opentsdb. Env "TAOS_ADAPTER_OPENTSDB_ENABLE" (default true)
      --opentsdb_telnet.dbs strings                  opentsdb_telnet db names. Env "TAOS_ADAPTER_OPENTSDB_TELNET_DBS" (default [opentsdb_telnet,collectd_tsdb,icinga2_tsdb,tcollector_tsdb])
      --opentsdb_telnet.enable                       enable opentsdb telnet,warning: without auth info(default false). Env "TAOS_ADAPTER_OPENTSDB_TELNET_ENABLE"
      --opentsdb_telnet.maxTCPConnections int        max tcp connections. Env "TAOS_ADAPTER_OPENTSDB_TELNET_MAX_TCP_CONNECTIONS" (default 250)
      --opentsdb_telnet.password string              opentsdb_telnet password. Env "TAOS_ADAPTER_OPENTSDB_TELNET_PASSWORD" (default "taosdata")
      --opentsdb_telnet.ports ints                   opentsdb telnet tcp port. Env "TAOS_ADAPTER_OPENTSDB_TELNET_PORTS" (default [6046,6047,6048,6049])
      --opentsdb_telnet.tcpKeepAlive                 enable tcp keep alive. Env "TAOS_ADAPTER_OPENTSDB_TELNET_TCP_KEEP_ALIVE"
      --opentsdb_telnet.user string                  opentsdb_telnet user. Env "TAOS_ADAPTER_OPENTSDB_TELNET_USER" (default "root")
      --pool.idleTimeout duration                    Set idle connection timeout. Env "TAOS_ADAPTER_POOL_IDLE_TIMEOUT" (default 1h0m0s)
      --pool.maxConnect int                          max connections to taosd. Env "TAOS_ADAPTER_POOL_MAX_CONNECT" (default 4000)
      --pool.maxIdle int                             max idle connections to taosd. Env "TAOS_ADAPTER_POOL_MAX_IDLE" (default 4000)
  -P, --port int                                     http port. Env "TAOS_ADAPTER_PORT" (default 6041)
      --prometheus.enable                            enable prometheus. Env "TAOS_ADAPTER_PROMETHEUS_ENABLE" (default true)
      --restfulRowLimit int                          restful returns the maximum number of rows (-1 means no limit). Env "TAOS_ADAPTER_RESTFUL_ROW_LIMIT" (default -1)
      --ssl.certFile string                          ssl cert file path. Env "TAOS_ADAPTER_SSL_CERT_FILE"
      --ssl.enable                                   enable ssl. Env "TAOS_ADAPTER_SSL_ENABLE"
      --ssl.keyFile string                           ssl key file path. Env "TAOS_ADAPTER_SSL_KEY_FILE"
      --statsd.allowPendingMessages int              statsd allow pending messages. Env "TAOS_ADAPTER_STATSD_ALLOW_PENDING_MESSAGES" (default 50000)
      --statsd.db string                             statsd db name. Env "TAOS_ADAPTER_STATSD_DB" (default "statsd")
      --statsd.deleteCounters                        statsd delete counter cache after gather. Env "TAOS_ADAPTER_STATSD_DELETE_COUNTERS" (default true)
      --statsd.deleteGauges                          statsd delete gauge cache after gather. Env "TAOS_ADAPTER_STATSD_DELETE_GAUGES" (default true)
      --statsd.deleteSets                            statsd delete set cache after gather. Env "TAOS_ADAPTER_STATSD_DELETE_SETS" (default true)
      --statsd.deleteTimings                         statsd delete timing cache after gather. Env "TAOS_ADAPTER_STATSD_DELETE_TIMINGS" (default true)
      --statsd.enable                                enable statsd. Env "TAOS_ADAPTER_STATSD_ENABLE" (default true)
      --statsd.gatherInterval duration               statsd gather interval. Env "TAOS_ADAPTER_STATSD_GATHER_INTERVAL" (default 5s)
      --statsd.maxTCPConnections int                 statsd max tcp connections. Env "TAOS_ADAPTER_STATSD_MAX_TCP_CONNECTIONS" (default 250)
      --statsd.password string                       statsd password. Env "TAOS_ADAPTER_STATSD_PASSWORD" (default "taosdata")
      --statsd.port int                              statsd server port. Env "TAOS_ADAPTER_STATSD_PORT" (default 6044)
      --statsd.protocol string                       statsd protocol [tcp or udp]. Env "TAOS_ADAPTER_STATSD_PROTOCOL" (default "udp")
      --statsd.tcpKeepAlive                          enable tcp keep alive. Env "TAOS_ADAPTER_STATSD_TCP_KEEP_ALIVE"
      --statsd.user string                           statsd user. Env "TAOS_ADAPTER_STATSD_USER" (default "root")
      --statsd.worker int                            statsd write worker. Env "TAOS_ADAPTER_STATSD_WORKER" (default 10)
      --taosConfigDir string                         load taos client config path. Env "TAOS_ADAPTER_TAOS_CONFIG_FILE"
      --version                                      Print the version and exit
```

Note:
Please set the following Cross-Origin Resource Sharing (CORS) parameters according to the actual situation when using a browser for interface calls.

```text
AllowAllOrigins
AllowOrigins
AllowHeaders
ExposeHeaders
AllowCredentials
AllowWebSockets
```

You do not need to care about these configurations if you do not make interface calls through the browser.

For details on the CORS protocol, please refer to: [https://www.w3.org/wiki/CORS_Enabled](https://www.w3.org/wiki/CORS_Enabled) or [https://developer.mozilla.org/zh-CN/docs/Web/HTTP/CORS](https://developer.mozilla.org/zh-CN/docs/Web/HTTP/CORS).

See [example/config/taosadapter.toml](https://github.com/taosdata/taosadapter/blob/develop/example/config/taosadapter.toml) for sample configuration files.

## Feature List

- Compatible with RESTful interfaces
  [https://www.taosdata.com/cn/documentation/connector#restful](https://www.taosdata.com/cn/documentation/connector#restful)
- Compatible with InfluxDB v1 write interface
  [https://docs.influxdata.com/influxdb/v2.0/reference/api/influxdb-1x/write/](https://docs.influxdata.com/influxdb/v2.0/reference/api/influxdb-1x/write/)
- Compatible with OpenTSDB JSON and telnet format writes
  - <http://opentsdb.net/docs/build/html/api_http/put.html>
  - <http://opentsdb.net/docs/build/html/api_telnet/put.html>
- Seamless connection to collectd
  collectd is a system statistics collection daemon, please visit [https://collectd.org/](https://collectd.org/) for more information.
- Seamless connection with StatsD
  StatsD is a simple yet powerful daemon for aggregating statistical information. Please visit [https://github.com/statsd/statsd](https://github.com/statsd/statsd) for more information.
- Seamless connection with icinga2
  icinga2 is a software that collects inspection result metrics and performance data. Please visit [https://icinga.com/docs/icinga-2/latest/doc/14-features/#opentsdb-writer](https://icinga.com/docs/icinga-2/latest/doc/14-features/#opentsdb-writer) for more information.
- Seamless connection to TCollector
  TCollector is a client process that collects data from a local collector and pushes the data to OpenTSDB. Please visit [http://opentsdb.net/docs/build/html/user_guide/utilities/tcollector.html](http://opentsdb.net/docs/build/html/user_guide/utilities/tcollector.html) for more information.
- Seamless connection to node_exporter
  node_export is an exporter for machine metrics. Please visit [https://github.com/prometheus/node_exporter](https://github.com/prometheus/node_exporter) for more information.
- Support for Prometheus remote_read and remote_write
  remote_read and remote_write are interfaces for Prometheus data read and write from/to other data storage solution. Please visit [https://prometheus.io/blog/2019/10/10/remote-read-meets-streaming/#remote-apis](https://prometheus.io/blog/2019/10/10/remote-read-meets-streaming/#remote-apis) for more information.

## Interfaces

### TDengine RESTful interface

You can use any client that supports the http protocol to write data to or query data from TDengine by accessing the REST interface address `http://<fqdn>:6041/<APIEndPoint>`. See the [official documentation](/reference/connector#restful) for details. The following EndPoint is supported.

```text
/rest/sql
/rest/sqlt
/rest/sqlutc
```

### InfluxDB

You can use any client that supports the http protocol to access the Restful interface address `http://<fqdn>:6041/<APIEndPoint>` to write data in InfluxDB compatible format to TDengine. The EndPoint is as follows:

```text
/influxdb/v1/write
```

Support InfluxDB query parameters as follows.

- `db` Specifies the database name used by TDengine
- `precision` The time precision used by TDengine
- `u` TDengine user name
- `p` TDengine password

Note: InfluxDB token authorization is not supported at present. Only Basic authorization and query parameter validation are supported.

### OpenTSDB

You can use any client that supports the http protocol to access the Restful interface address `http://<fqdn>:6041/<APIEndPoint>` to write data in OpenTSDB compatible format to TDengine.

```text
/opentsdb/v1/put/json/:db
/opentsdb/v1/put/telnet/:db
```

### collectd

<CollectD />

### StatsD

<StatsD />

### icinga2 OpenTSDB writer

<Icinga2 />

### TCollector

<TCollector />

### node_exporter

node_export is an exporter of hardware and OS metrics exposed by the \*NIX kernel used by Prometheus

- Enable the taosAdapter configuration `node_exporter.enable`
- Set the configuration of the node_exporter
- Restart taosAdapter

### Prometheus

<Prometheus />

## Memory usage optimization methods

taosAdapter will monitor its memory usage during operation and adjust it with two thresholds. Valid values range from -1 to 100 integers in percent of the system's physical memory.

- pauseQueryMemoryThreshold
- pauseAllMemoryThreshold

Stops processing query requests when the `pauseQueryMemoryThreshold` threshold is exceeded.

HTTP response content.

- code 503
- body "query memory exceeds threshold"

Stops processing all write and query requests when the `pauseAllMemoryThreshold` threshold is exceeded.

HTTP response: code 503

- code 503
- body "memory exceeds threshold"

Resume the corresponding function when the memory falls back below the threshold.

Status check interface `http://<fqdn>:6041/-/ping`

- Normal returns `code 200`
- No parameter If memory exceeds pauseAllMemoryThreshold returns `code 503`
- Request parameter `action=query` returns `code 503` if memory exceeds `pauseQueryMemoryThreshold` or `pauseAllMemoryThreshold`

Corresponding configuration parameter

``text
  monitor.collectDuration monitoring interval environment variable `TAOS_MONITOR_COLLECT_DURATION` (default value 3s)
  monitor.incgroup whether to run in cgroup (set to true for running in container) environment variable `TAOS_MONITOR_INCGROUP`
  monitor.pauseAllMemoryThreshold memory threshold for no more inserts and queries environment variable `TAOS_MONITOR_PAUSE_ALL_MEMORY_THRESHOLD` (default 80)
  monitor.pauseQueryMemoryThreshold memory threshold for no more queries Environment variable `TAOS_MONITOR_PAUSE_QUERY_MEMORY_THRESHOLD` (default 70)
```

You can adjust it according to the specific application scenario and operation strategy, and it is recommended to use operation monitoring software to monitor system memory status timely. The load balancer can also check the taosAdapter running status through this interface.

## taosAdapter Monitoring Metrics

taosAdapter collects HTTP-related metrics, CPU percentage, and memory percentage.

### HTTP interface

Provides an interface conforming to [OpenMetrics](https://github.com/OpenObservability/OpenMetrics/blob/main/specification/OpenMetrics.md).

```text
http://<fqdn>:6041/metrics
```

### Write to TDengine

taosAdapter supports writing the metrics of HTTP monitoring, CPU percentage, and memory percentage to TDengine.

For configuration parameters

| **Configuration items** | **Description** | **Default values** |
| ----------------------- | --------------------------------------------------------- | ---------- |
| monitor.collectDuration | CPU and memory collection interval | 3s |
| monitor.identity | The current taosadapter identifier will be used if not set to `hostname:port` | |
| monitor.incgroup | whether it is running in a cgroup (set to true for running in a container) | false |
| monitor.writeToTD | Whether to write to TDengine | true |
| monitor.user | TDengine connection username | root |
| monitor.password | TDengine connection password | taosdata |
| monitor.writeInterval | Write to TDengine interval | 30s |

## Limit the number of results returned

taosAdapter controls the number of results returned by the parameter `restfulRowLimit`, -1 means no limit, default is no limit.

This parameter controls the number of results returned by the following interfaces:

- `http://<fqdn>:6041/rest/sql`
- `http://<fqdn>:6041/rest/sqlt`
- `http://<fqdn>:6041/rest/sqlutc`
- ` http://<fqdn>:6041/prometheus/v1/remote_read/:db`

## Troubleshooting

You can check the taosAdapter running status with the `systemctl status taosadapter` command.

You can also adjust the level of the taosAdapter log output by setting the `--logLevel` parameter or the environment variable `TAOS_ADAPTER_LOG_LEVEL`. Valid values are: panic, fatal, error, warn, warning, info, debug and trace.

## How to migrate from older TDengine versions to taosAdapter

In TDengine server 2.2.x.x or earlier, the TDengine server process (taosd) contains an embedded HTTP service. As mentioned earlier, taosAdapter is a standalone software managed using `systemd` and has its process ID. And there are some configuration parameters and behaviors that are different between the two. See the following table for details.

| **#** | **embedded httpd** | **taosAdapter** | **comment** |
| ----- | ------------------- | ------------------------------------ | ------------------------------------------------------------------ ------------------------------------------------------------------------ |
| 1 | httpEnableRecordSql | --logLevel=debug | |
| 2 | httpMaxThreads | n/a | taosAdapter Automatically manages thread pools without this parameter |
| 3 | telegrafUseFieldNum | See the taosAdapter telegraf configuration method | |
| 4 | restfulRowLimit | restfulRowLimit | Embedded httpd outputs 10240 rows of data by default, the maximum allowed is 102400. taosAdapter also provides restfulRowLimit but it is not limited by default. You can configure it according to the actual scenario.
| 5 | httpDebugFlag | Not applicable | httpdDebugFlag does not work for taosAdapter |
| 6 | httpDBNameMandatory | N/A | taosAdapter requires the database name to be specified in the URL |