Redis 錯誤：Failed with result 'start-limit-hit'

Redis 錯誤：Failed with result 'start-limit-hit'

背景

Redis 版本爲 5.0.4；

文件 /etc/systemd/system/redis.service 內容以下：

[Unit]
Description=Redis Datastore Server
After=network.target

[Service]
Type=forking
PIDFile=/var/run/redis/redis_6379
User=redis
Group=redis

Environment=statedir=/var/run/redis
PermissionsStartOnly=true
ExecStartPre=/bin/mkdir -p ${statedir}
ExecStartPre=/bin/chown -R redis:redis ${statedir}
ExecStart=/usr/local/bin/redis-server /etc/redis/redis.conf --supervised systemd
ExecReload=/bin/kill -USR2 $MAINPID
ExecStop=/usr/local/bin/redis-cli shutdown
Restart=always

[Install]
WantedBy=multi-user.target

運行

在使用 systemctl 啓動 Redis 時報錯：

sudo systemctl daemon-reload
sudo systemctl start redis

錯誤日誌：

Job for redis-server.service failed because the control process exited with error code. See "systemctl status redis-server.service" and "journalctl -xe" for details.

根據提示用命令 systemctl status redis-server.service 查看結果以下：

● redis-server.service - Redis Datastore Server
   Loaded: loaded (/lib/systemd/system/redis-server.service; enabled; vendor preset: enabled)
   Active: failed (Result: start-limit-hit) since Thu 2019-04-18 15:36:10 CST; 5s ago
  Process: 8341 ExecStart=/usr/bin/redis-server /etc/redis/redis.conf --supervised systemd (code=exited
  Process: 8337 ExecStartPre=/bin/chown -R redis:redis ${statedir} (code=exited, status=0/SUCCESS)
  Process: 8333 ExecStartPre=/bin/mkdir -p ${statedir} (code=exited, status=0/SUCCESS)

Apr 18 15:36:10 dl26 systemd[1]: Failed to start Redis Datastore Server.
Apr 18 15:36:10 dl26 systemd[1]: redis-server.service: Unit entered failed state.
Apr 18 15:36:10 dl26 systemd[1]: redis-server.service: Failed with result 'exit-code'.
Apr 18 15:36:10 dl26 systemd[1]: redis-server.service: Service hold-off time over, scheduling restart.
Apr 18 15:36:10 dl26 systemd[1]: Stopped Redis Datastore Server.
Apr 18 15:36:10 dl26 systemd[1]: redis-server.service: Start request repeated too quickly.
Apr 18 15:36:10 dl26 systemd[1]: Failed to start Redis Datastore Server.
Apr 18 15:36:10 dl26 systemd[1]: redis-server.service: Unit entered failed state.
Apr 18 15:36:10 dl26 systemd[1]: redis-server.service: Failed with result 'start-limit-hit'.

發現 ExecStart=/usr/bin/redis-server /etc/redis/redis.conf --supervised systemd 報錯，執行該命令出現以下錯誤日誌：

*** FATAL CONFIG FILE ERROR ***
Reading the configuration file, at line 88
>>> 'protected-mode yes'
Bad directive or wrong number of arguments

問題是在處理配置文件時出現參數不匹配現象，緣由是由於我在用源碼安裝 redis 後還用 apt-get install redis 的方法安裝了一箇舊版本的 redis，在 /usr/bin/ 目錄下的 redis-server 不是最新版本，故出現不兼容的問題。

解決方法：

cp -r redis/src/redis-server /usr/bin/redis-server

再次執行：

sudo systemctl daemon-reload
sudo systemctl start redis

仍然報一樣的錯誤，執行/usr/bin/redis-server /etc/redis/redis.conf --supervised systemd，日誌以下：

8436:C 18 Apr 2019 15:37:50.558 # Can't chdir to '/home/chenxiang/redis': No such file or directory

發現是目錄名稱不存在，文件 /etc/redis/redis.conf 中的目錄名稱爲 /home/chenxiang/redis，而實際 redis 目錄名稱爲 /home/chenxiang/redis-5.0.4，修改實際目錄名稱爲 redis 即解決這一問題。

繼續運行：

sudo systemctl daemon-reload
sudo systemctl start redis

出現了新的錯誤：

Job for redis-server.service failed because a timeout was exceeded. See "systemctl status redis-server.service" and "journalctl -xe" for details.

經過 systemctl status redis-server.service 查看日誌信息：

● redis-server.service - Redis Datastore Server
   Loaded: loaded (/lib/systemd/system/redis-server.service; enabled; vendor preset: enabled)
   Active: activating (start) since Thu 2019-04-18 15:49:48 CST; 1min 21s ago
  Process: 8533 ExecStart=/usr/bin/redis-server /etc/redis/redis.conf --supervised systemd (code=exited
  Process: 8530 ExecStartPre=/bin/chown -R redis:redis ${statedir} (code=exited, status=0/SUCCESS)
  Process: 8527 ExecStartPre=/bin/mkdir -p ${statedir} (code=exited, status=0/SUCCESS)
   CGroup: /system.slice/redis-server.service
           └─8535 /usr/bin/redis-server 127.0.0.1:6379                            

Apr 18 15:49:48 dl26 systemd[1]: Starting Redis Datastore Server...
Apr 18 15:49:48 dl26 redis-server[8533]: 8533:C 18 Apr 2019 15:49:48.250 # oO0OoO0OoO0Oo Redis is start
Apr 18 15:49:48 dl26 redis-server[8533]: 8533:C 18 Apr 2019 15:49:48.250 # Redis version=5.0.4, bits=64
Apr 18 15:49:48 dl26 redis-server[8533]: 8533:C 18 Apr 2019 15:49:48.250 # Configuration loaded
Apr 18 15:49:48 dl26 redis-server[8533]: 8533:C 18 Apr 2019 15:49:48.250 # systemd supervision requeste
Apr 18 15:49:48 dl26 systemd[1]: redis-server.service: PID file /var/run/redis/redis_6379 not readable

發現 redis-server.service 沒有足夠的權限訪問 /var/run/redis/redis_6379，須要修改/etc/systemd/system/redis.service爲：

[Unit]
Description=Redis Datastore Server
After=network.target

[Service]
Type=forking
PIDFile=/var/run/redis/redis.pid
User=redis
Group=redis

Environment=statedir=/var/run/redis
PermissionsStartOnly=true
ExecStartPre=/bin/mkdir -p ${statedir}
ExecStartPre=/bin/chown -R redis:redis ${statedir}
ExecStartPost=/bin/sh -c "echo 6739 > /var/run/redis/redis.pid"
ExecStart=/usr/local/bin/redis-server /etc/redis/redis.conf --supervised systemd
ExecReload=/bin/kill -USR2 $MAINPID
ExecStop=/usr/local/bin/redis-cli shutdown
Restart=always

[Install]
WantedBy=multi-user.target

其中修改兩行：PIDFile=/var/run/redis/redis.pid，以及 ExecStartPost=/bin/sh -c "echo 6739 > /var/run/redis/redis.pid"。

2019.4