by XDK
3. October 2019 22:10
Explanation:
Following is the command
aws cloudwatch set-alarm-state --alarm-name <Created alarm name> --state-reason <comment> --state-value ALARM
by XDK
28. September 2019 01:39
Explanation:
Launch an EC2 instance for which the custom CloudWatch memory metrics need to be generated.
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Create an IAM role named "CustomMetricsRole" with a custom policy name "CustomEC2CloudWatch" to establish the interoperability between EC2 instance and CloudWatch as below
Policy : CustomEC2CloudWatch
Permissions:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "VisualEditor0",
"Effect": "Allow",
"Action": [
"cloudwatch:GetMetricStatistics",
"cloudwatch:PutMetricData",
"cloudwatch:GetMetricData",
"ec2:DescribeTags",
"cloudwatch:ListMetrics"
],
"Resource": "*"
}
]
}
Attach IAM role to the EC2 instance
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SSH to EC2 instance
$ sudo apt update
$ sudo apt install unzip
$ sudo apt install perl
$ sudo apt install liblwp-protocol-https-perl libdatetime-perl
Download the CloudWatch Monitoring perl scripts for Linux
$ wget http://aws-cloudwatch.s3.amazonaws.com/downloads/CloudWatchMonitoringScripts-1.2.1.zip
$ unzip CloudWatchMonitoringScripts-1.2.1.zip
$ cd aws-scripts-mon
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mon-put-instance-data.pl - Collects system metrics on an EC2 instance and sends them to CloudWatch
mon-get-instance-stats.pl - Queries CloudWatch and displays the most resent metrics
AwsSignatureV4.pm - File template for AWS credentials
Push custom metrics from EC2 instance to CloudWatch
$ ./mon-put-instance-data.pl --mem-util --mem-used --mem-avail
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Create crontab and add the script to run at every minute intervals.
$ crontab -e
* * * * * /home/ubuntu/aws-scripts-mon/mon-put-instance-data.pl --mem-util --mem-used --mem-avail
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To retrive the most recent custom metrics from CloudWatch to EC2 instance
$ ./mon-get-instance-stats.pl
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