如何使用systemd运行多个redis实例

Question

最近我转到Debian 8 "Jessie“，它现在使用systemd，我找不到运行多个redis实例的方法。

我发现在重启时有一个/lib/systemd/system/redis-server.service文件可以启动redis服务器。因此，我创建了一个包含以下内容的新文件调用/lib/systemd/system/redis-server-2.service：

[Unit]
Description=Advanced key-value store
After=network.target

[Service]
Type=forking
ExecStart=/usr/bin/redis-server /etc/redis/redis-2.conf
TimeoutStopSec=0
Restart=always
User=redis
Group=redis

[Install]
WantedBy=multi-user.target

但是，当我尝试像这样启动服务：service redis-server-2 start时，我得到了以下错误：

Job for redis-server-2.service failed. See 'systemctl status redis-server-2.service' and 'journalctl -xn' for details.

systemctl status redis-server-2.service给了我：

● redis-server-2.service - Advanced key-value store
   Loaded: loaded (/lib/systemd/system/redis-server-2.service; disabled)
   Active: failed (Result: start-limit) since Sat 2015-10-10 11:09:54 CEST; 33s ago
  Process: 2473 ExecStart=/usr/bin/redis-server /etc/redis/redis-2.conf (code=exited, status=1/FAILURE)
 Main PID: 2371 (code=exited, status=1/FAILURE)

Oct 10 11:09:54 server101 systemd[1]: redis-server-2.service: control process exited, code=exited status=1
Oct 10 11:09:54 server101 systemd[1]: Failed to start Advanced key-value store.
Oct 10 11:09:54 server101 systemd[1]: Unit redis-server-2.service entered failed state.
Oct 10 11:09:54 server101 systemd[1]: redis-server-2.service start request repeated too quickly, refusing to start.
Oct 10 11:09:54 server101 systemd[1]: Failed to start Advanced key-value store.
Oct 10 11:09:54 server101 systemd[1]: Unit redis-server-2.service entered failed state.

这对我没什么帮助。

但是，如果我运行/usr/bin/redis-server /etc/redis/redis-2.conf，我的redis实例就会正确启动。

那么，你知道为什么系统不自己启动这个实例吗？

提前谢谢你的帮助。

Answer 1

正如迈克尔·汉普顿所建议的，我查看了syslog，发现：

Oct 10 11:33:46 server101 redis-server[1947]: *** FATAL CONFIG FILE ERROR ***
Oct 10 11:33:46 server101 redis-server[1947]: Reading the configuration file, at line 5
Oct 10 11:33:46 server101 redis-server[1947]: >>> 'logfile /var/log/redis/redis-server-2.log'
Oct 10 11:33:46 server101 redis-server[1947]: Can't open the log file: Permission denied

所以我不得不这么做来解决这个问题：

chown redis:redis /var/log/redis/redis-server-2.log