Collecting Classic Load Balancer logs using the Lambda Function
IP-based routing requests handled by Classic Load Balancers provide useful log data that can be used for troubleshooting issues with load balancers and back-end instances. Site24x7 acts as a unified web console that gives you the ability to search log entries and alert you about threshold breaches. Learn more about log management with Site24x7.
Site24x7 is AWS-reviewed Lambda Service Ready Program Partner
Create a Log Profile
To collect the Classic Load Balancer logs you will first need to create a Log Profile. Navigate to Admin > AppLogs > Log Profile > Add Log Profile, and follow the instructions below:
- Profile Name: Enter a name for your Log Profile.
- Log Type: Choose ELB Classic Log. If you haven't enabled ELB access logs in your AWS account, please follow the instructions given here.
- Log Source: Choose Amazon Lambda.
- Click Save.
- Configure the Lambda function as described here.
Configure the Lambda Function
- Choose Lambda from the Services drop-down list, and choose Create Function. Select Author from scratch, define a name for the function, and choose Python 3.7 as the Runtime.
- Permissions: You can choose an existing IAM role or create a new role from the AWS Policy Template. From the Policy Template drop-down select Amazon S3 Object Read-only permission, and enter a role name. You also have the option to create a new user role and extend permission to other services as well.
- Add triggers: Scroll down to choose S3 Bucket. Any log file added to the S3 bucket will be sent to Site24x7 by the Lambda Function.
- Configure Triggers
- Bucket:Enter the name of the S3 bucket from which logs will be collected.
- Event type: Choose All object create events.
- Click Add.
- In the window that opens, click on the Lambda Function as shown:
- Scroll to the editor, and place the code provided in the link below:
- After entering the code, navigate to the Site24x7 web client, select Admin > Applogs > Log Profile, then select the created Log Profile, and copy the code that appears on the screen as the input for the variable logTypeConfig under the field.
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- Paste this code under Environment Variable with the field name logTypeConfig in the AWS console.
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ELB Classic Load Balancer logs dashboard
AppLogs creates an exclusive dashboard for every Log Type, and shows a few widgets by default. Here's a list of the widgets available in the Classic Load Balancer logs dashboard:
- Average Bytes Transferred
- Request Processing Time
- Backend Processing Time
- Response Processing Time
- Request Trend
- ELB Status Code Stats
- User Agent Stats
- Top 20 Failed Requests
- Errors By Client Host