Azure虚拟机中ThingsBoard未监听指定端口求助

我在Azure云的Ubuntu 20.04虚拟机上安装并运行ThingsBoard服务器，按照官方教程操作后，服务看似启动正常，但无法访问。为避免端口冲突，我把端口改成了8081，但问题依旧。

执行curl http://localhost:8081/时收到以下错误：

ahontanb@vm-tfg:~$ curl http://localhost:8081/
curl: (7) Failed to connect to localhost port 8081: Connection refused

查看虚拟机监听端口（执行sudo netstat -a）的输出如下：

ahontanb@vm-tfg:~$ sudo netstat -a
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State
tcp        0      0 localhost:postgresql    0.0.0.0:*               LISTEN
tcp        0      0 localhost:6010          0.0.0.0:*               LISTEN
tcp        0      0 localhost:domain        0.0.0.0:*               LISTEN
tcp        0      0 localhost:postgresql    localhost:35046         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:35032         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:35026         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:54638         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:55832         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:42512         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:35052         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:55424         ESTABLISHED
tcp        0      0 localhost:postgresql    localhost:40720         ESTABLISHED
tcp6       0      0 ip6-localhost:6010      [::]:*                  LISTEN
tcp6       0      0 [::]:7070               [::]:*                  LISTEN
tcp6       0      0 [::]:1883               [::]:*                  LISTEN
tcp6       0      0 127.0.0.1:35026         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:55832         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:35032         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:35046         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:35052         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:55424         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:40720         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:54638         127.0.0.1:postgresql    ESTABLISHED
tcp6       0      0 127.0.0.1:42512         127.0.0.1:postgresql    ESTABLISHED
udp        0      0 localhost:323           0.0.0.0:*
udp        0      0 localhost:domain        0.0.0.0:*
udp        0      0 vm-tfg.internal.:bootpc 0.0.0.0:*
udp        0      0 localhost:52982         localhost:52982         ESTABLISHED
udp6       0      0 ip6-localhost:323       [::]:*
udp6       0      0 [::]:5683               [::]:*
raw6       0      0 [::]:ipv6-icmp          [::]:*                  7

可以看到MQTT的1883端口处于监听状态，但8081端口未出现在监听列表中。

我的thingsboard.conf配置内容如下：

#
# Copyright © 2016-2023 The Thingsboard Authors
#
# Licensed 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.
#

export JAVA_OPTS="$JAVA_OPTS -Dplatform=deb -Dinstall.data_dir=/usr/share/thingsboard/data"
export JAVA_OPTS="$JAVA_OPTS -Xlog:gc*,heap*,age*,safepoint=debug:file=/var/log/thingsboard/gc.log:time,uptime,level,tags:filecount=10,filesize=10M"
export JAVA_OPTS="$JAVA_OPTS -XX:+IgnoreUnrecognizedVMOptions -XX:+HeapDumpOnOutOfMemoryError"
export JAVA_OPTS="$JAVA_OPTS -XX:-UseBiasedLocking -XX:+UseTLAB -XX:+ResizeTLAB -XX:+PerfDisableSharedMem -XX:+UseCondCardMark"
export JAVA_OPTS="$JAVA_OPTS -XX:+UseG1GC -XX:MaxGCPauseMillis=500 -XX:+UseStringDeduplication -XX:+ParallelRefProcEnabled -XX:MaxTenuringThreshold=10"
export LOG_FILENAME=thingsboard.out
export LOADER_PATH=/usr/share/thingsboard/conf,/usr/share/thingsboard/extensions
export SQL_DATA_FOLDER=/usr/share/thingsboard/data/sql
# DB Configuration
export DATABASE_TS_TYPE=sql
export SPRING_DATASOURCE_URL=jdbc:postgresql://localhost:5432/thingsboard
export SPRING_DATASOURCE_USERNAME=postgres
export SPRING_DATASOURCE_PASSWORD=ahbgs2000
# Specify partitioning size for timestamp key-value storage. Allowed values: DAYS, MONTHS, YEARS, INDEFINITE.
export SQL_POSTGRES_TS_KV_PARTITIONING=MONTHS
# Update ThingsBoard memory usage and restrict it to 256MB in /etc/thingsboard/conf/thingsboard.conf
export JAVA_OPTS="$JAVA_OPTS -Xms256M -Xmx256M"
export TB_QUEUE_TYPE=in-memory

export export HTTP_BIND_PORT=8081

问题排查与解决建议 #

1. 修复配置文件语法错误 #

配置最后一行存在重复的export关键字：export export HTTP_BIND_PORT=8081，这会导致系统无法正确识别该环境变量。
修复操作：将该行修改为export HTTP_BIND_PORT=8081，删除多余的export。

2. 重启ThingsBoard服务 #

修改配置后必须重启服务才能生效，执行命令：

sudo systemctl restart thingsboard

3. 验证服务状态与日志 #

确认服务是否正常启动：

sudo systemctl status thingsboard

若服务启动失败，查看日志排查具体错误：

cat /var/log/thingsboard/thingsboard.out

或实时查看系统日志：

journalctl -u thingsboard -f

4. 检查端口监听状态 #

重启服务后，再次验证8081端口是否处于监听状态：

sudo netstat -tulpn | grep 8081

或使用ss命令：

sudo ss -tulpn | grep 8081

5. Azure安全组配置（如需外部访问） #

如果需要从虚拟机外部访问8081端口，需在Azure网络安全组（NSG）中添加入站规则，允许TCP 8081端口的流量通过。

内容的提问来源于stack exchange，提问作者Alejandro Hontanilla