配置为 dockerized postgres 时，pgbouncer 无法启动答案

【问题标题】：pgbouncer fails to start when configured to dockerized postgres配置为 dockerized postgres 时，pgbouncer 无法启动
【发布时间】：2021-08-14 19:53:32
【问题描述】：

我是第一次尝试配置 pgbouncer。

我的 postgres 数据库作为容器运行（端口为 5011）

我的操作系统是 debian 10。

我使用 apt-install 来安装 pgbouncer：

sudo apt-get install pgbouncer

然后可以看到 pgbouncer 状态正常：

# sudo systemctl status pgbouncer
● pgbouncer.service - LSB: start pgbouncer
   Loaded: loaded (/etc/init.d/pgbouncer; generated)
   Active: active (running) since Wed 2021-05-26 16:15:49 IDT; 11min ago
     Docs: man:systemd-sysv-generator(8)
    Tasks: 2 (limit: 4915)
   Memory: 2.4M
   CGroup: /system.slice/pgbouncer.service
           └─4392 /usr/sbin/pgbouncer -d /etc/pgbouncer/pgbouncer.ini

我的数据库名称是 mydb，postgres 容器在 5011 端口上运行，所以我这样配置 /etc/pgbouncer/pgbouncer.ini：

[databases]
octopus-bouncer = host=10.1.1.1 port=5011 user=dbauser dbname=mydb

;; Configuration section
[pgbouncer]
auth_file = userlist.txt

; IP address or * which means all IPs
listen_addr = *
listen_port = 6432

; any, trust, plain, crypt, md5, cert, hba, pam
auth_type = md5
auth_file = /etc/pgbouncer/userlist.txt

; total number of clients that can connect
max_client_conn = 100

; default pool size.  20 is good number when transaction pooling
; is in use, in session pooling it needs to be the number of
; max clients you want to handle at any moment
default_pool_size = 20

我终于把我的用户放到/etc/pgbouncer/userlist.txt：

"dbauser" "mypassword"

然后我重新启动了 pgbouncer - 但失败了：

# sudo systemctl restart pgbouncer
Job for pgbouncer.service failed because the control process exited with error code.
See "systemctl status pgbouncer.service" and "journalctl -xe" for details.

状态只显示这个：

# sudo systemctl status pgbouncer
● pgbouncer.service - LSB: start pgbouncer
   Loaded: loaded (/etc/init.d/pgbouncer; generated)
   Active: failed (Result: exit-code) since Wed 2021-05-26 17:04:00 IDT; 2min 3s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 28111 ExecStart=/etc/init.d/pgbouncer start (code=exited, status=1/FAILURE)

May 26 17:04:00 Octopus systemd[1]: Starting LSB: start pgbouncer...
May 26 17:04:00 Octopus pgbouncer[28111]: Starting PgBouncer: pgbouncer failed!
May 26 17:04:00 Octopus systemd[1]: pgbouncer.service: Control process exited, code=exited, status=1/FAILURE
May 26 17:04:00 Octopus systemd[1]: pgbouncer.service: Failed with result 'exit-code'.
May 26 17:04:00 Octopus systemd[1]: Failed to start LSB: start pgbouncer.

我错过了什么吗？如何调试问题？

【问题讨论】：

我设法通过从 postgres 用户而不是 root 启动它来启动 pgbouncer，并使用以下命令：/usr/sbin/pgbouncer -d -R -v /etc/pgbouncer/pgbouncer.ini . pgbouncer 日志显示 pgbouncer 已启动并运行：2021-05-27 16:38:50.475 19862 LOG process up: pgbouncer 1.9.0, libevent 2.1.8-stable (epoll), adns: c-ares 1.14.0, tls ：OpenSSL 1.1.1d 2019 年 9 月 10 日。但是，当尝试使用 psql 从容器登录到 psql 到 pgbouncer 端口 6432 时出现错误：psql：错误：没有这样的数据库：mydb

标签： pgbouncer

【解决方案1】：

您可以将 KillSignal=SIGINT 添加到服务单元文件中：

cat /usr/lib/systemd/system/pgbouncer.service
[Unit]
Description=A lightweight connection pooler for PostgreSQL
Documentation=man:pgbouncer(1)
After=syslog.target network.target

[Service]
RemainAfterExit=yes

User=postgres
Group=postgres

# Path to the init file
Environment=BOUNCERCONF=/etc/pgbouncer/pgbouncer.ini

#Environment=SYSTEMD_LOG_LEVEL=debug

ExecStart=/usr/bin/pgbouncer -q ${BOUNCERCONF}
ExecReload=/usr/bin/pgbouncer -R -q ${BOUNCERCONF}
KillSignal=SIGINT

# Give a reasonable amount of time for the server to start up/shut down
TimeoutSec=300

[Install]
WantedBy=multi-user.target

来自 pgbouncer 人：

Signals
   SIGHUP Reload config.  Same as issuing the command RELOAD on the console.
   SIGINT Safe shutdown.  Same as issuing PAUSE and SHUTDOWN on the console.

【讨论】：