redis.exceptions.ConnectionError: Error -2 连接到 localhost:6379。 名称或服务未知

Question

在服务器中运行代码时出现此错误，我的环境是 debian，而Python2.7.3

Traceback (most recent call last):
  File "fetcher.py", line 4, in <module>
    import mirad.fetcher_tasks as tasks
  File "/home/mirad/backend/mirad/fetcher_tasks.py", line 75, in <module>
    redis_keys = r.keys('*')
  File "/home/mirad/backend/venv/local/lib/python2.7/site-packages/redis/client.py", line 863, in keys
    return self.execute_command('KEYS', pattern)
  File "/home/mirad/backend/venv/local/lib/python2.7/site-packages/redis/client.py", line 534, in execute_command
    connection.send_command(*args)
  File "/home/mirad/backend/venv/local/lib/python2.7/site-packages/redis/connection.py", line 532, in send_command
    self.send_packed_command(self.pack_command(*args))
  File "/home/mirad/backend/venv/local/lib/python2.7/site-packages/redis/connection.py", line 508, in send_packed_command
    self.connect()
  File "/home/mirad/backend/venv/local/lib/python2.7/site-packages/redis/connection.py", line 412, in connect
    raise ConnectionError(self._error_message(e))
redis.exceptions.ConnectionError: Error -2 connecting to localhost:6379. Name or service not known.

当我运行redis-cli它可以正常工作，没有任何错误：

$ redis-cli 
127.0.0.1:6379> 

Answer 1

您似乎正在尝试将 redis 连接到您当前的 Debian 环境无法识别的服务器。 从 Traceback，我看到您正在尝试使用主机名作为 localhost 进行连接，

r_server=redis.Redis(host="localhost",port=6379)

但是，您的系统无法理解“localhost”，请在主机文件中输入，即说 127.0.0.1 是 localhost。 在 /etc/hosts 中添加以下代码

127.0.0.1 localhost

否则使用以下命令连接redis；

r_server=redis.Redis(host="127.0.0.1",port=6379) 
 

Answer 2

我遇到了类似的问题，后来意识到我没有通过命令在终端中打开 redis：$ redis-server。 也许是这样。