:doc:`Alarm <index>` / Attribute / dimensions

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dimensions
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.. py:attribute:: CloudWatch.Alarm.dimensions

  

  - *(list) --* 

    The dimensions for the metric associated with the alarm.

    
    

    - *(dict) --* 

      A dimension is a name/value pair that is part of the identity of a metric. Because dimensions are part of the unique identifier for a metric, whenever you add a unique name/value pair to one of your metrics, you are creating a new variation of that metric. For example, many Amazon EC2 metrics publish ``InstanceId`` as a dimension name, and the actual instance ID as the value for that dimension.

       

      You can assign up to 30 dimensions to a metric.

      
      

      - **Name** *(string) --* 

        The name of the dimension. Dimension names must contain only ASCII characters, must include at least one non-whitespace character, and cannot start with a colon ( ``:``). ASCII control characters are not supported as part of dimension names.

        
      

      - **Value** *(string) --* 

        The value of the dimension. Dimension values must contain only ASCII characters and must include at least one non-whitespace character. ASCII control characters are not supported as part of dimension values.

        
  
