mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-25 09:02:00 +00:00
145 lines
6.1 KiB
Markdown
145 lines
6.1 KiB
Markdown
---
|
||
toc_priority: 46
|
||
toc_title: Troubleshooting
|
||
---
|
||
|
||
# Troubleshooting {#troubleshooting}
|
||
|
||
- [Installation](#troubleshooting-installation-errors)
|
||
- [Connecting to the server](#troubleshooting-accepts-no-connections)
|
||
- [Query processing](#troubleshooting-does-not-process-queries)
|
||
- [Efficiency of query processing](#troubleshooting-too-slow)
|
||
|
||
## Installation {#troubleshooting-installation-errors}
|
||
|
||
### You Cannot Get Deb Packages from ClickHouse Repository with Apt-get {#you-cannot-get-deb-packages-from-clickhouse-repository-with-apt-get}
|
||
|
||
- Check firewall settings.
|
||
- If you cannot access the repository for any reason, download packages as described in the [Getting started](../getting-started/index.md) article and install them manually using the `sudo dpkg -i <packages>` command. You will also need the `tzdata` package.
|
||
|
||
## Connecting to the Server {#troubleshooting-accepts-no-connections}
|
||
|
||
Possible issues:
|
||
|
||
- The server is not running.
|
||
- Unexpected or wrong configuration parameters.
|
||
|
||
### Server Is Not Running {#server-is-not-running}
|
||
|
||
**Check if server is runnnig**
|
||
|
||
Command:
|
||
|
||
``` bash
|
||
$ sudo service clickhouse-server status
|
||
```
|
||
|
||
If the server is not running, start it with the command:
|
||
|
||
``` bash
|
||
$ sudo service clickhouse-server start
|
||
```
|
||
|
||
**Check logs**
|
||
|
||
The main log of `clickhouse-server` is in `/var/log/clickhouse-server/clickhouse-server.log` by default.
|
||
|
||
If the server started successfully, you should see the strings:
|
||
|
||
- `<Information> Application: starting up.` — Server started.
|
||
- `<Information> Application: Ready for connections.` — Server is running and ready for connections.
|
||
|
||
If `clickhouse-server` start failed with a configuration error, you should see the `<Error>` string with an error description. For example:
|
||
|
||
``` text
|
||
2019.01.11 15:23:25.549505 [ 45 ] {} <Error> ExternalDictionaries: Failed reloading 'event2id' external dictionary: Poco::Exception. Code: 1000, e.code() = 111, e.displayText() = Connection refused, e.what() = Connection refused
|
||
```
|
||
|
||
If you don’t see an error at the end of the file, look through the entire file starting from the string:
|
||
|
||
``` text
|
||
<Information> Application: starting up.
|
||
```
|
||
|
||
If you try to start a second instance of `clickhouse-server` on the server, you see the following log:
|
||
|
||
``` text
|
||
2019.01.11 15:25:11.151730 [ 1 ] {} <Information> : Starting ClickHouse 19.1.0 with revision 54413
|
||
2019.01.11 15:25:11.154578 [ 1 ] {} <Information> Application: starting up
|
||
2019.01.11 15:25:11.156361 [ 1 ] {} <Information> StatusFile: Status file ./status already exists - unclean restart. Contents:
|
||
PID: 8510
|
||
Started at: 2019-01-11 15:24:23
|
||
Revision: 54413
|
||
|
||
2019.01.11 15:25:11.156673 [ 1 ] {} <Error> Application: DB::Exception: Cannot lock file ./status. Another server instance in same directory is already running.
|
||
2019.01.11 15:25:11.156682 [ 1 ] {} <Information> Application: shutting down
|
||
2019.01.11 15:25:11.156686 [ 1 ] {} <Debug> Application: Uninitializing subsystem: Logging Subsystem
|
||
2019.01.11 15:25:11.156716 [ 2 ] {} <Information> BaseDaemon: Stop SignalListener thread
|
||
```
|
||
|
||
**See system.d logs**
|
||
|
||
If you don’t find any useful information in `clickhouse-server` logs or there aren’t any logs, you can view `system.d` logs using the command:
|
||
|
||
``` bash
|
||
$ sudo journalctl -u clickhouse-server
|
||
```
|
||
|
||
**Start clickhouse-server in interactive mode**
|
||
|
||
``` bash
|
||
$ sudo -u clickhouse /usr/bin/clickhouse-server --config-file /etc/clickhouse-server/config.xml
|
||
```
|
||
|
||
This command starts the server as an interactive app with standard parameters of the autostart script. In this mode `clickhouse-server` prints all the event messages in the console.
|
||
|
||
### Configuration Parameters {#configuration-parameters}
|
||
|
||
Check:
|
||
|
||
- Docker settings.
|
||
|
||
If you run ClickHouse in Docker in an IPv6 network, make sure that `network=host` is set.
|
||
|
||
- Endpoint settings.
|
||
|
||
Check [listen_host](../operations/server-configuration-parameters/settings.md#server_configuration_parameters-listen_host) and [tcp_port](../operations/server-configuration-parameters/settings.md#server_configuration_parameters-tcp_port) settings.
|
||
|
||
ClickHouse server accepts localhost connections only by default.
|
||
|
||
- HTTP protocol settings.
|
||
|
||
Check protocol settings for the HTTP API.
|
||
|
||
- Secure connection settings.
|
||
|
||
Check:
|
||
|
||
- The [tcp_port_secure](../operations/server-configuration-parameters/settings.md#server_configuration_parameters-tcp_port_secure) setting.
|
||
- Settings for [SSL certificates](../operations/server-configuration-parameters/settings.md#server_configuration_parameters-openssl).
|
||
|
||
Use proper parameters while connecting. For example, use the `port_secure` parameter with `clickhouse_client`.
|
||
|
||
- User settings.
|
||
|
||
You might be using the wrong user name or password.
|
||
|
||
## Query Processing {#troubleshooting-does-not-process-queries}
|
||
|
||
If ClickHouse is not able to process the query, it sends an error description to the client. In the `clickhouse-client` you get a description of the error in the console. If you are using the HTTP interface, ClickHouse sends the error description in the response body. For example:
|
||
|
||
``` bash
|
||
$ curl 'http://localhost:8123/' --data-binary "SELECT a"
|
||
Code: 47, e.displayText() = DB::Exception: Unknown identifier: a. Note that there are no tables (FROM clause) in your query, context: required_names: 'a' source_tables: table_aliases: private_aliases: column_aliases: public_columns: 'a' masked_columns: array_join_columns: source_columns: , e.what() = DB::Exception
|
||
```
|
||
|
||
If you start `clickhouse-client` with the `stack-trace` parameter, ClickHouse returns the server stack trace with the description of an error.
|
||
|
||
You might see a message about a broken connection. In this case, you can repeat the query. If the connection breaks every time you perform the query, check the server logs for errors.
|
||
|
||
## Efficiency of Query Processing {#troubleshooting-too-slow}
|
||
|
||
If you see that ClickHouse is working too slowly, you need to profile the load on the server resources and network for your queries.
|
||
|
||
You can use the clickhouse-benchmark utility to profile queries. It shows the number of queries processed per second, the number of rows processed per second, and percentiles of query processing times.
|