community/developer-guide/be-vscode-dev.md - doris-website - Git at Google

 ---
 title: BE Development Environment Setup - Visual Studio Code (VSCode)
 language: en
 description: "Set up the Apache Doris BE development environment with VSCode: compilation, GDB/LLDB debugging, and core dump analysis."
 keywords:
     - VSCode
     - Apache Doris BE
     - BE development environment
     - GDB debugging
     - LLDB debugging
     - core dump
     - doris_be
 ---

 <!--
 Licensed to the Apache Software Foundation (ASF) under one
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 regarding copyright ownership.  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

 Unless required by applicable law or agreed to in writing,
 software 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.
 -->

 # Setting Up a BE Development and Debugging Environment with VSCode

 This document describes how to compile, start, and debug Apache Doris BE using VSCode on Ubuntu 20.04, covering three debugging methods: GDB, LLDB, and core dump.

 > The BE binary is named `doris_be`. In older versions it was named `palo_be`.

 <!-- Knowledge type: Procedure -->
 <!-- Applicable scenario: IDE configuration / Debugging setup -->

 ## 1. Prerequisites

 1. Download the Doris source code: [apache/doris on GitHub](https://github.com/apache/doris)

 2. Install the base toolchain: GCC 8.3.1+, Oracle JDK 1.8+, Python 2.7+. Verify that `gcc`, `java`, and `python` point to the correct versions, and set the `JAVA_HOME` environment variable.

 3. Install other dependencies:

     ```bash
     sudo apt install build-essential openjdk-8-jdk maven cmake byacc flex automake libtool-bin bison binutils-dev libiberty-dev zip unzip libncurses5-dev curl git ninja-build python brotli
     sudo add-apt-repository ppa:ubuntu-toolchain-r/ppa
     sudo apt update
     sudo apt install gcc-10 g++-10
     sudo apt-get install autoconf automake libtool autopoint
     ```

 4. Install OpenSSL:

     ```bash
     sudo apt install -y openssl libssl-dev
     ```

 ## 2. Compilation

 The following steps are performed under the `/home/workspace` directory.

 ### 2.1 Download the Source Code

 ```bash
 git clone https://github.com/apache/doris.git
 cd doris
 git submodule update --init --recursive
 ```

 ### 2.2 Compile Third-Party Dependencies

 ```bash
 cd /home/workspace/doris/thirdparty
 ./build-thirdparty.sh
 ```

 ### 2.3 Compile Doris

 ```bash
 cd /home/workspace/doris
 ./build.sh
 ```

 `build.sh` supports the following combinations:

 | Command                             | Description                |
 | ----------------------------------- | -------------------------- |
 | `./build.sh`                        | Compile both BE and FE     |
 | `./build.sh --be`                   | Compile BE only            |
 | `./build.sh --fe`                   | Compile FE only            |
 | `./build.sh --fe --be`              | Compile both BE and FE     |
 | `./build.sh --fe --be --clean`      | Clean, then compile both BE and FE |
 | `./build.sh --fe --clean`           | Clean, then compile FE     |
 | `./build.sh --be --clean`           | Clean, then compile BE     |

 Build artifacts are output to the `/home/workspace/doris/output/` directory. For problems, refer to the [Doris official documentation](http://doris.apache.org).

 :::tip Private Maven Repository
 When compiling FE, if you need to specify a private Maven repository, use the `USER_SETTINGS_MVN_REPO` environment variable to point to the `settings.xml` path:

 ```bash
 export USER_SETTINGS_MVN_REPO="/xxx/xxx/settings.xml"
 ```
 :::

 ## 3. Deployment and Debugging (GDB)

 ### 3.1 Grant Execute Permission to the BE Binary

 ```bash
 chmod +x /home/workspace/doris/output/be/lib/doris_be
 ```

 `/home/workspace/doris/output/be/lib/doris_be` is the BE executable.

 ### 3.2 Create the Data Storage Directory

 Check `/home/workspace/doris/output/be/conf/be.conf`:

 ```bash
 # INFO, WARNING, ERROR, FATAL
 sys_log_level = INFO
 be_port = 9060
 be_rpc_port = 9070
 webserver_port = 8040
 heartbeat_service_port = 9050
 brpc_port = 8060
 arrow_flight_sql_port = -1

 # Note that there should at most one ip match this list.
 # If no ip match this rule, will choose one randomly.
 # use CIDR format, e.g. 10.10.10.0/
 # Default value is empty.
 priority_networks = 192.168.59.0/24 # data root path, separate by ';'
 storage_root_path = /soft/be/storage
 ```

 Create the data directory based on `storage_root_path`:

 ```bash
 mkdir -p /soft/be/storage
 ```

 ### 3.3 Open the Source Code and Install the Debugging Extension

 1. Open the BE source code directory with VSCode (in this example, `/home/workspace/doris/`).
 2. Install the VSCode **C/C++** (ms-vscode.cpptools) debugging extension.

     ![](/images/image-20210618104004956.png)

 ### 3.4 Create launch.json

 <!-- Knowledge type: Configuration parameters -->

 Create a Launch-mode configuration in `.vscode/launch.json`:

 ```json
 {
     "version": "0.2.0",
     "configurations": [
         {
             "name": "(gdb) Launch",
             "type": "cppdbg",
             "request": "launch",
             "program": "/home/workspace/doris/output/be/lib/doris_be",
             "args": [],
             "stopAtEntry": false,
             "cwd": "/home/workspace/doris/",
             "environment": [
                 {"name": "DORIS_HOME", "value": "/home/workspace/doris/output/be/"},
                 {"name": "UDF_RUNTIME_DIR", "value": "/home/workspace/doris/output/be/lib/udf-runtime"},
                 {"name": "LOG_DIR", "value": "/home/workspace/doris/output/be/log"},
                 {"name": "PID_DIR", "value": "/home/workspace/doris/output/be/bin"}
             ],
             "externalConsole": true,
             "MIMode": "gdb",
             "miDebuggerPath": "/path/to/gdb",
             "setupCommands": [
                 {
                     "description": "Enable pretty-printing for gdb",
                     "text": "-enable-pretty-printing",
                     "ignoreFailures": true
                 }
             ]
         }
     ]
 }
 ```

 `environment` defines the environment variables required by `doris_be` at runtime. Startup fails if they are not set:

 | Environment variable | Purpose                    |
 | -------------------- | -------------------------- |
 | `DORIS_HOME`         | BE runtime root directory  |
 | `UDF_RUNTIME_DIR`    | UDF runtime directory      |
 | `LOG_DIR`            | Log directory              |
 | `PID_DIR`            | PID file directory         |

 `miDebuggerPath` specifies the debugger path (for example, `gdb`). If it is not specified, the system `PATH` is searched. The GDB version shipped with the system may be too old, so you may need to specify the path to a newer version manually.

 ### 3.5 Attach-Mode Debugging

 To attach to a running BE process, use the following configuration:

 ```json
 {
     "version": "0.2.0",
     "configurations": [
         {
             "name": "(gdb) Launch",
             "type": "cppdbg",
             "request": "attach",
             "program": "/home/workspace/doris/output/lib/doris_be",
             "processId": "${command:pickProcess}",
             "MIMode": "gdb",
             "miDebuggerPath": "/path/to/gdb",
             "internalConsoleOptions": "openOnSessionStart",
             "setupCommands": [
                 {
                     "description": "Enable pretty-printing for gdb",
                     "text": "-enable-pretty-printing",
                     "ignoreFailures": true
                 }
             ]
         }
     ]
 }
 ```

 Key points:

 - `"request": "attach"`: sets the debugging mode to attach.
 - `"processId"`: the PID of the process to attach to. It can be a specific number, `"${command:pickProcess}"` (select manually at startup), or extracted with the following command:

     ```bash
     lsof -i | grep -m 1 doris_be | awk "{print $2}"
     ```

     ![](/images/image-20210618095240216.png)

     In the image above, `15200` is the current BE process ID.

 ### 3.6 Complete launch.json Example

 The following is a complete configuration that includes both **Launch** and **Attach** modes:

 ```json
 {
     "version": "0.2.0",
     "configurations": [
         {
             "name": "(gdb) Attach",
             "type": "cppdbg",
             "request": "attach",
             "program": "/home/workspace/doris/output/be/lib/doris_be",
             "processId": 17016,
             "MIMode": "gdb",
             "miDebuggerPath": "/path/to/gdb",
             "setupCommands": [
                 {
                     "description": "Enable pretty-printing for gdb",
                     "text": "-enable-pretty-printing",
                     "ignoreFailures": true
                 }
             ]
         },
         {
             "name": "(gdb) Launch",
             "type": "cppdbg",
             "request": "launch",
             "program": "/home/workspace/doris/output/be/lib/doris_be",
             "args": [],
             "stopAtEntry": false,
             "cwd": "/home/workspace/doris/output/be",
             "environment": [
                 {"name": "DORIS_HOME", "value": "/home/workspace/doris/output/be"},
                 {"name": "UDF_RUNTIME_DIR", "value": "/home/workspace/doris/output/be/lib/udf-runtime"},
                 {"name": "LOG_DIR", "value": "/home/workspace/doris/output/be/log"},
                 {"name": "PID_DIR", "value": "/home/workspace/doris/output/be/bin"}
             ],
             "externalConsole": false,
             "MIMode": "gdb",
             "miDebuggerPath": "/path/to/gdb",
             "setupCommands": [
                 {
                     "description": "Enable pretty-printing for gdb",
                     "text": "-enable-pretty-printing",
                     "ignoreFailures": true
                 }
             ]
         }
     ]
 }
 ```

 ### 3.7 Start Debugging

 Click the VSCode debug button to begin debugging Doris BE.

 ![](/images/image-20210618091006146.png)

 ## 4. Debugging (LLDB)

 LLDB attaches faster than GDB and is used in a similar way. The VSCode extension to install is `CodeLLDB`, then add the following configuration to launch.json:

 ```json
 {
     "name": "CodeLLDB attach",
     "type": "lldb",
     "request": "attach",
     "program": "${workspaceFolder}/output/be/lib/doris_be",
     "pid": "${command:pickMyProcess}"
 }
 ```

 :::caution glibc Version Requirement
 This method requires the system `glibc` version to be `2.18+`. If this is not satisfied, refer to [How to make CodeLLDB work on CentOS7](https://gist.github.com/JaySon-Huang/63dcc6c011feb5bd6deb1ef0cf1a9b96) to install a newer glibc and link it to the extension.
 :::

 ## 5. Debugging Core Dump Files

 To debug a core file produced by a BE crash, add the following to the corresponding configuration entry:

 ```json
 "coreDumpPath": "/PATH/TO/CORE/DUMP/FILE"
 ```

 ## 6. Common Debugging Tips

 ### 6.1 Function Execution Path

 When you are not familiar with the BE execution details, use tools such as `perf` to trace function calls and identify the call chain. For `perf` usage, see [Debugging Tools](./debug-tool).

 Run the SQL you want to trace on a large table, then increase the sampling frequency (for example, `perf -F 999`). Observing the results gives a rough picture of the critical path of the SQL on BE.

 ### 6.2 Debugging CRTP Objects

 To improve runtime efficiency, the BE code heavily uses CRTP (Curiously Recurring Template Pattern) in base types, which prevents the debugger from inspecting an object as its derived type. You can work around this in GDB as follows:

 Suppose you need to debug an object `col` of type `IColumn` but do not know its actual type:

 ```bash
 set print object on   # Print objects by derived type
 p *col.t              # Use col.t to get the concrete type of col
 p col.t->size()       # Use it as the derived type, for example, ColumnString supports size()
 ```

 :::caution
 The polymorphic effect applies to the pointer `COW::t`, not the `IColumn` class object. You must replace every use of `col` with `col.t` in GDB to actually obtain the derived-type object.
 :::

 ## 7. Frequently Asked Questions (FAQ)

 <!-- Knowledge type: Troubleshooting -->

 ### Q1: BE Exits Immediately After Startup

 Environment variables are not set, or paths do not exist. Verify that `DORIS_HOME`, `LOG_DIR`, `PID_DIR`, and `UDF_RUNTIME_DIR` are all set and that the corresponding directories have been created.

 ### Q2: GDB Reports a Version Too Low or an Unsupported Feature

 The GDB version shipped with the system is outdated. Install a newer GDB manually and specify it in `miDebuggerPath`.

 ### Q3: CodeLLDB Fails to Load

 The system `glibc` version is lower than `2.18`. Refer to the link in section 4 to resolve this.

 ### Q4: Maven Fails to Reach the External Network When Compiling FE

 Set the `USER_SETTINGS_MVN_REPO` environment variable to point to the `settings.xml` of a private Maven repository. See the tip in section 2.3.
	---
	title: BE Development Environment Setup - Visual Studio Code (VSCode)
	language: en
	description: "Set up the Apache Doris BE development environment with VSCode: compilation, GDB/LLDB debugging, and core dump analysis."
	keywords:
	- VSCode
	- Apache Doris BE
	- BE development environment
	- GDB debugging
	- LLDB debugging
	- core dump
	- doris_be
	---

	<!--
	Licensed to the Apache Software Foundation (ASF) under one
	or more contributor license agreements. See the NOTICE file
	distributed with this work for additional information
	regarding copyright ownership. 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

	Unless required by applicable law or agreed to in writing,
	software 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.
	-->

	# Setting Up a BE Development and Debugging Environment with VSCode

	This document describes how to compile, start, and debug Apache Doris BE using VSCode on Ubuntu 20.04, covering three debugging methods: GDB, LLDB, and core dump.

	> The BE binary is named `doris_be`. In older versions it was named `palo_be`.

	<!-- Knowledge type: Procedure -->
	<!-- Applicable scenario: IDE configuration / Debugging setup -->

	## 1. Prerequisites

	1. Download the Doris source code: [apache/doris on GitHub](https://github.com/apache/doris)

	2. Install the base toolchain: GCC 8.3.1+, Oracle JDK 1.8+, Python 2.7+. Verify that `gcc`, `java`, and `python` point to the correct versions, and set the `JAVA_HOME` environment variable.

	3. Install other dependencies:

	```bash
	sudo apt install build-essential openjdk-8-jdk maven cmake byacc flex automake libtool-bin bison binutils-dev libiberty-dev zip unzip libncurses5-dev curl git ninja-build python brotli
	sudo add-apt-repository ppa:ubuntu-toolchain-r/ppa
	sudo apt update
	sudo apt install gcc-10 g++-10
	sudo apt-get install autoconf automake libtool autopoint
	```

	4. Install OpenSSL:

	```bash
	sudo apt install -y openssl libssl-dev
	```

	## 2. Compilation

	The following steps are performed under the `/home/workspace` directory.

	### 2.1 Download the Source Code

	```bash
	git clone https://github.com/apache/doris.git
	cd doris
	git submodule update --init --recursive
	```

	### 2.2 Compile Third-Party Dependencies

	```bash
	cd /home/workspace/doris/thirdparty
	./build-thirdparty.sh
	```

	### 2.3 Compile Doris

	```bash
	cd /home/workspace/doris
	./build.sh
	```

	`build.sh` supports the following combinations:

	\| Command \| Description \|
	\| ----------------------------------- \| -------------------------- \|
	\| `./build.sh` \| Compile both BE and FE \|
	\| `./build.sh --be` \| Compile BE only \|
	\| `./build.sh --fe` \| Compile FE only \|
	\| `./build.sh --fe --be` \| Compile both BE and FE \|
	\| `./build.sh --fe --be --clean` \| Clean, then compile both BE and FE \|
	\| `./build.sh --fe --clean` \| Clean, then compile FE \|
	\| `./build.sh --be --clean` \| Clean, then compile BE \|

	Build artifacts are output to the `/home/workspace/doris/output/` directory. For problems, refer to the [Doris official documentation](http://doris.apache.org).

	:::tip Private Maven Repository
	When compiling FE, if you need to specify a private Maven repository, use the `USER_SETTINGS_MVN_REPO` environment variable to point to the `settings.xml` path:

	```bash
	export USER_SETTINGS_MVN_REPO="/xxx/xxx/settings.xml"
	```
	:::

	## 3. Deployment and Debugging (GDB)

	### 3.1 Grant Execute Permission to the BE Binary

	```bash
	chmod +x /home/workspace/doris/output/be/lib/doris_be
	```

	`/home/workspace/doris/output/be/lib/doris_be` is the BE executable.

	### 3.2 Create the Data Storage Directory

	Check `/home/workspace/doris/output/be/conf/be.conf`:

	```bash
	# INFO, WARNING, ERROR, FATAL
	sys_log_level = INFO
	be_port = 9060
	be_rpc_port = 9070
	webserver_port = 8040
	heartbeat_service_port = 9050
	brpc_port = 8060
	arrow_flight_sql_port = -1

	# Note that there should at most one ip match this list.
	# If no ip match this rule, will choose one randomly.
	# use CIDR format, e.g. 10.10.10.0/
	# Default value is empty.
	priority_networks = 192.168.59.0/24 # data root path, separate by ';'
	storage_root_path = /soft/be/storage
	```

	Create the data directory based on `storage_root_path`:

	```bash
	mkdir -p /soft/be/storage
	```

	### 3.3 Open the Source Code and Install the Debugging Extension

	1. Open the BE source code directory with VSCode (in this example, `/home/workspace/doris/`).
	2. Install the VSCode C/C++ (ms-vscode.cpptools) debugging extension.

	![](/images/image-20210618104004956.png)

	### 3.4 Create launch.json

	<!-- Knowledge type: Configuration parameters -->

	Create a Launch-mode configuration in `.vscode/launch.json`:

	```json
	{
	"version": "0.2.0",
	"configurations": [
	{
	"name": "(gdb) Launch",
	"type": "cppdbg",
	"request": "launch",
	"program": "/home/workspace/doris/output/be/lib/doris_be",
	"args": [],
	"stopAtEntry": false,
	"cwd": "/home/workspace/doris/",
	"environment": [
	{"name": "DORIS_HOME", "value": "/home/workspace/doris/output/be/"},
	{"name": "UDF_RUNTIME_DIR", "value": "/home/workspace/doris/output/be/lib/udf-runtime"},
	{"name": "LOG_DIR", "value": "/home/workspace/doris/output/be/log"},
	{"name": "PID_DIR", "value": "/home/workspace/doris/output/be/bin"}
	],
	"externalConsole": true,
	"MIMode": "gdb",
	"miDebuggerPath": "/path/to/gdb",
	"setupCommands": [
	{
	"description": "Enable pretty-printing for gdb",
	"text": "-enable-pretty-printing",
	"ignoreFailures": true
	}
	]
	}
	]
	}
	```

	`environment` defines the environment variables required by `doris_be` at runtime. Startup fails if they are not set:

	\| Environment variable \| Purpose \|
	\| -------------------- \| -------------------------- \|
	\| `DORIS_HOME` \| BE runtime root directory \|
	\| `UDF_RUNTIME_DIR` \| UDF runtime directory \|
	\| `LOG_DIR` \| Log directory \|
	\| `PID_DIR` \| PID file directory \|

	`miDebuggerPath` specifies the debugger path (for example, `gdb`). If it is not specified, the system `PATH` is searched. The GDB version shipped with the system may be too old, so you may need to specify the path to a newer version manually.

	### 3.5 Attach-Mode Debugging

	To attach to a running BE process, use the following configuration:

	```json
	{
	"version": "0.2.0",
	"configurations": [
	{
	"name": "(gdb) Launch",
	"type": "cppdbg",
	"request": "attach",
	"program": "/home/workspace/doris/output/lib/doris_be",
	"processId": "${command:pickProcess}",
	"MIMode": "gdb",
	"miDebuggerPath": "/path/to/gdb",
	"internalConsoleOptions": "openOnSessionStart",
	"setupCommands": [
	{
	"description": "Enable pretty-printing for gdb",
	"text": "-enable-pretty-printing",
	"ignoreFailures": true
	}
	]
	}
	]
	}
	```

	Key points:

	- `"request": "attach"`: sets the debugging mode to attach.
	- `"processId"`: the PID of the process to attach to. It can be a specific number, `"${command:pickProcess}"` (select manually at startup), or extracted with the following command:

	```bash
	lsof -i \| grep -m 1 doris_be \| awk "{print $2}"
	```

	![](/images/image-20210618095240216.png)

	In the image above, `15200` is the current BE process ID.

	### 3.6 Complete launch.json Example

	The following is a complete configuration that includes both Launch and Attach modes:

	```json
	{
	"version": "0.2.0",
	"configurations": [
	{
	"name": "(gdb) Attach",
	"type": "cppdbg",
	"request": "attach",
	"program": "/home/workspace/doris/output/be/lib/doris_be",
	"processId": 17016,
	"MIMode": "gdb",
	"miDebuggerPath": "/path/to/gdb",
	"setupCommands": [
	{
	"description": "Enable pretty-printing for gdb",
	"text": "-enable-pretty-printing",
	"ignoreFailures": true
	}
	]
	},
	{
	"name": "(gdb) Launch",
	"type": "cppdbg",
	"request": "launch",
	"program": "/home/workspace/doris/output/be/lib/doris_be",
	"args": [],
	"stopAtEntry": false,
	"cwd": "/home/workspace/doris/output/be",
	"environment": [
	{"name": "DORIS_HOME", "value": "/home/workspace/doris/output/be"},
	{"name": "UDF_RUNTIME_DIR", "value": "/home/workspace/doris/output/be/lib/udf-runtime"},
	{"name": "LOG_DIR", "value": "/home/workspace/doris/output/be/log"},
	{"name": "PID_DIR", "value": "/home/workspace/doris/output/be/bin"}
	],
	"externalConsole": false,
	"MIMode": "gdb",
	"miDebuggerPath": "/path/to/gdb",
	"setupCommands": [
	{
	"description": "Enable pretty-printing for gdb",
	"text": "-enable-pretty-printing",
	"ignoreFailures": true
	}
	]
	}
	]
	}
	```

	### 3.7 Start Debugging

	Click the VSCode debug button to begin debugging Doris BE.

	![](/images/image-20210618091006146.png)

	## 4. Debugging (LLDB)

	LLDB attaches faster than GDB and is used in a similar way. The VSCode extension to install is `CodeLLDB`, then add the following configuration to launch.json:

	```json
	{
	"name": "CodeLLDB attach",
	"type": "lldb",
	"request": "attach",
	"program": "${workspaceFolder}/output/be/lib/doris_be",
	"pid": "${command:pickMyProcess}"
	}
	```

	:::caution glibc Version Requirement
	This method requires the system `glibc` version to be `2.18+`. If this is not satisfied, refer to [How to make CodeLLDB work on CentOS7](https://gist.github.com/JaySon-Huang/63dcc6c011feb5bd6deb1ef0cf1a9b96) to install a newer glibc and link it to the extension.
	:::

	## 5. Debugging Core Dump Files

	To debug a core file produced by a BE crash, add the following to the corresponding configuration entry:

	```json
	"coreDumpPath": "/PATH/TO/CORE/DUMP/FILE"
	```

	## 6. Common Debugging Tips

	### 6.1 Function Execution Path

	When you are not familiar with the BE execution details, use tools such as `perf` to trace function calls and identify the call chain. For `perf` usage, see [Debugging Tools](./debug-tool).

	Run the SQL you want to trace on a large table, then increase the sampling frequency (for example, `perf -F 999`). Observing the results gives a rough picture of the critical path of the SQL on BE.

	### 6.2 Debugging CRTP Objects

	To improve runtime efficiency, the BE code heavily uses CRTP (Curiously Recurring Template Pattern) in base types, which prevents the debugger from inspecting an object as its derived type. You can work around this in GDB as follows:

	Suppose you need to debug an object `col` of type `IColumn` but do not know its actual type:

	```bash
	set print object on # Print objects by derived type
	p *col.t # Use col.t to get the concrete type of col
	p col.t->size() # Use it as the derived type, for example, ColumnString supports size()
	```

	:::caution
	The polymorphic effect applies to the pointer `COW::t`, not the `IColumn` class object. You must replace every use of `col` with `col.t` in GDB to actually obtain the derived-type object.
	:::

	## 7. Frequently Asked Questions (FAQ)

	<!-- Knowledge type: Troubleshooting -->

	### Q1: BE Exits Immediately After Startup

	Environment variables are not set, or paths do not exist. Verify that `DORIS_HOME`, `LOG_DIR`, `PID_DIR`, and `UDF_RUNTIME_DIR` are all set and that the corresponding directories have been created.

	### Q2: GDB Reports a Version Too Low or an Unsupported Feature

	The GDB version shipped with the system is outdated. Install a newer GDB manually and specify it in `miDebuggerPath`.

	### Q3: CodeLLDB Fails to Load

	The system `glibc` version is lower than `2.18`. Refer to the link in section 4 to resolve this.

	### Q4: Maven Fails to Reach the External Network When Compiling FE

	Set the `USER_SETTINGS_MVN_REPO` environment variable to point to the `settings.xml` of a private Maven repository. See the tip in section 2.3.