python boto 脚本中 EC2 实例的 DiskSpaceUtilization 指标显示空响应

Question

我想获取 DiskSpaceUtilization 指标的数据点，但 get_metrics_statitics 的响应为空。

get_metrics_statitics 函数完美适用于其他指标，即 CPUUtilization、MemoryUtilization。但是相同的代码不适用于 DiskSpaceUtilization。

我尝试了以下代码：

import sys
from datetime import datetime as dt, timedelta
import boto3

metricdictionary = {}
metricdictionary['DiskSpaceUtilization'] = 'System/Linux,Percent'

ec2_resource = boto3.resource("ec2")
cloudwatch = boto3.client("cloudwatch")

date = dt.today() - timedelta(days=1)
year = date.year
month = date.month
day = date.day

response = cloudwatch.get_metric_statistics(Namespace='System/Linux', 
                            MetricName='DiskSpaceUtilization', 
                            Dimensions=[{'Name': 'InstanceId', 
                            'Value': 'i-0a22a230c4dae4195', }],                                
                            StartTime=dt(year, month, day, 00, 00, 00),
                            EndTime=dt(year, month, day, 23, 59, 59),
                            Period=3600, 
                            Statistics=['Average', 'Minimum', 'Maximum'],
                            Unit='Percent')

print response

提前致谢。

Answer 1

那是因为除了InstanceId，还需要指定两个额外的维度：Filesystem和MountPath。

AWS Developer Forums 中报告了类似的问题。如果您不想对这两个维度进行硬编码，请查看注释：

One way to avoid using instance-specific filesystem dimensions is to modify the mon-put-instance-data.pl script and just comment out the part that adds Filesystem and MountPath dimensions, leaving only InstanceId dimension for the reported disk metrics. When making these modifications, try running mon-put-instance-data.pl script from the command line with --verify --verbose options to see what data will be actually sent over to Amazon CloudWatch service.

编辑：如果您想使用 Python 获得这两个维度，您可以执行类似的操作：

#!/usr/bin/env python

import subprocess

mounts = {}

for line in subprocess.check_output(['mount', '-l']).split('\n'):
    parts = line.split(' ')
    if len(parts) > 2:
        mounts[parts[2]] = parts[0]

print mounts

参考：https://askubuntu.com/questions/189987/get-device-with-mount-point

Answer 2

我修改了 get_metric_statistics 函数，它运行良好。对于磁盘 Space 利用率，我们需要添加额外的两个维度，即 FileSystem 和 Mountpath.

response = cloudwatch.get_metric_statistics(
    Namespace=namesp, MetricName='DiskSpaceUtilization',
    Dimensions=[
        {'Name': 'InstanceId', 'Value': instance['InstanceId'], },
        {'Name': 'Filesystem', 'Value': name_of_file_system},
        {'Name': 'MountPath', 'Value': MountPath_for_filesystem}
    ],
    StartTime=dt(year, month, day, 00, 00, 00),
    EndTime=dt(year, month, day, 23, 59, 59),
    Period=3600, Statistics=['Average', 'Minimum', 'Maximum'],
    Unit='Percent')

python boto 脚本中 EC2 实例的 DiskSpaceUtilization 指标显示空响应

DiskSpaceUtilization metrics for EC2 instance in python boto script showing empty response

amazon-ec2

amazon-web-services

python-2.7

amazon-cloudwatch

boto3