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Elastic Compute Cloud (EC2) is one of the most widely used services provided by AWS. Therefore, EC2 service limits become an important aspect to take into account while measuring your infrastructure’s health and robustness.
Do you check limits on your EC2 auto scaling groups regularly?
Amazon Elastic Compute Cloud service has a defined limit on the number of EC2 instances that a user can group under a particular auto scaling group. Users should be constantly keeping a check on this limit so that it does not get crossed before they could get hold of it.
The following are the default limits for EC2 auto scaling groups, defined by AWS:
- Auto Scaling groups per Region: 200
- Scaling policies per Auto Scaling group: 50
- Scheduled actions per Auto Scaling group: 125
- Lifecycle hooks per Auto Scaling group: 50
- SNS topics per Auto Scaling group: 10
- Classic Load Balancers per Auto Scaling group: 50
- Target groups per Auto Scaling group: 50
How does Centilytics assist you?
Centilytics helps AWS users by showing the status of their EC2 auto scaling groups’ limit in a particular region. The users also get severity warnings when the limit is about to be crossed so that they can put a request for increasing the defined limit.
Insight descriptions:
There can be three possible scenarios:
| Severity | Description |
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This indication will be displayed when the user has breached 100% of the specified limit of Amazon EC2 auto scaling groups. |
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This indication will be displayed when the user has breached 80% of the specified limit of the corresponding resource. |
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This indication will be displayed when the user has breached less than 80% of the specified limit of Elastic Compute Cloud auto scaling groups. |
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Performance Optimization Tip 101
Do not configure large number of security group rules in your AWS EC2 instances
Description of further columns are as follows:
- Account Id: This column shows the respective account ID of the user’s account.
- Account Name: This column shows the corresponding account name to the user’s account.
- Region: This column shows the region in which the corresponding resource exists.
- Limit Amount: This column shows the limit of the resource which is available. Here, the limit refers to the number of auto scaling groups available to the user in a region.
- Current usage: This column shows the current usage level of the corresponding resource.
- Service: This column shows the type of service limit.
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Compliances covered:
| Compliance Name | Reference No. | Link |
| Trusted Advisor | – | https://console.aws.amazon.com/trustedadvisor/home?#/category/service-limits |
Filters applicable:
| Filter Name | Description |
| Account Id | Applying the account Id filter will display all the resources for the selected account Id. |
| Region | Applying the region filter will display all the resources corresponding to the selected region. |
| Severity | Applying severity filter will display the resources according to the selected severity type i.e. selecting critical will display all resources with critical severity. Same will be the case for Warning and Ok severity types. |
To know more about EC2 auto scaling groups and their service limits read here:
[1] Amazon Elastic Compute Cloud auto scaling groups[2] Service limits on Elastic Compute Cloud auto scaling groups