Amazon Elastic Load Balancing

Amazon Elastic Load Balancing - An Overview

Elastic Load Balancing (ELB) is a load-balancing service from Amazon Web Services (AWS). AWS ELB automatically distributes incoming application traffic across multiple targets, such as EC2 instances, and scales resources to meet traffic demands. Elastic Load Balancing helps IT teams adjust capacity according to incoming application and network traffic.

AWS ELB supports three types of load balancers: Application Load Balancers, Network Load Balancers, and Gateway Load Balancers.

The Application Load Balancer handles advanced traffic routing from other services or containers at the application level.
The Network Load Balancer is ideal for load balancing of TCP traffic and capable of handling millions of requests per second while maintaining low latencies.
The Gateway Load Balancer simplifies the deployment and management of virtual appliances like firewalls and intrusion detection systems by distributing and scaling traffic.

Monitoring Amazon Elastic Load Balancing - What We do

This page discusses how Applications Manager's AWS ELB monitoring gives you the ability to monitor your load balancers, analyze traffic patterns and troubleshoot issues with your load balancers and targets for optimized performance.

Gather real-time performance data - Get basic data about the number of healthy hosts, latency, requests, error rates and more.
Analyze connection count statistics - Monitor the number of rejected connections to follow your Load Balancer’s ability to properly connect to a target and route a request. Measure the number of rules and bytes processed by the Application ELB.
Track healthy and unhealthy host count - Monitor the number of healthy targets registered with the Application Elastic Load Balancer. Maintain a Healthy Host Count by tracking healthy instances
Troubleshoot and monitor target HTTP error response codes - Gather statistics on the number of Client and Server errors generated by the load balancer. Measure the number of TLS connections that could not successfully establish a session between your load balancer and its registered instances. Get an aggregate of HTTP 4XX and 5XX error codes generated by the targets in your group.
Detect real-time performance issues and fix them faster - Understand the scalability of your ELB system and get a jumpstart on monitoring the Load Balancers in your environment. Applications Manager provides the ability to monitor your ELB configuration with detailed metrics about the requests made to your load balancers.
Get instant notifications of performance issues and bottlenecks. Take quick remedial action before your end-users experience issues.

Creating a new Amazon ALB/NLB/GLB monitor

To learn how to create a new Amazon ALB/NLB/GLB monitor, refer here.

Monitored Parameters

Go to the Monitors Category View by clicking the Monitors tab. Click on ALB or NLB or GLB in the Amazon Instances under the Cloud Apps Table. Displayed is the bulk configuration view distributed into three tabs:

Availability tab gives the Availability history for the past 24 hours or 30 days.
Performance tab gives the Health Status and events for the past 24 hours or 30 days.
List view enables you to perform bulk admin configurations.

Click on the monitor name to see all the Amazon ALB metrics listed under the following tabs:

Click on the monitor name to see all the Amazon NLB metrics listed under the following tabs:

Click on the monitor name to see all the Amazon GLB metrics listed under the following tabs:

Applications Load Balancer (ALB) Metrics

Applications Load Balancer - Overview

Parameter	Description
AVERAGE LATENCY
Average Target Latency	The average time taken from the load balancer forwarding a request until the target began sending response headers, between the poll interval (in Seconds).
HOST STATE BREAKDOWN
Healthy Hosts	The total targets passing health checks across every target group on this load balancer, at the time of polling.
Unhealthy Hosts	The total targets failing health checks across every target group on this load balancer, at the time of polling.
CAPACITY UTILIZATION
Capacity Utilization	The average share of the provisioned capacity of the load balancer that is in use, at the time of polling (in %).
CONSUMED LB CAPACITY UNITS
Consumed Capacity Units	The total load balancer capacity units consumed, which is what AWS bills for, between the poll interval.
Peak Load Balancer Capacity Units	The maximum load balancer capacity units consumed in any single minute, which is the figure to size reserved capacity against, between the poll interval.
Reserved Load Balancer Capacity Units	The total load balancer capacity units held by a reserved capacity configuration, at the time of polling.
REQUESTS
Requests / Min	The rate of requests processed by the load balancer, between the poll interval.
Total Requests	The total requests processed over IPv4 and IPv6, between the poll interval.
CONNECTIONS
Active Connections	The total concurrent TCP connections open from clients to the load balancer and from the load balancer to targets, between the poll interval.
New Connections	The total new TCP connections established from clients to the load balancer and from the load balancer to targets, between the poll interval.
Rejected Connections	The total connections rejected because the load balancer had reached its maximum number of connections, between the poll interval.
PROCESSED BYTES
Data processed / Min	The rate of amount of data processed by the load balancer, between the poll interval (in kB/Min).
Data processed	The total amount of data processed over IPv4 and IPv6, including request and response bodies, between the poll interval (in kB).
RULE EVALUATIONS
Rule Evaluations	The total listener rules evaluated, which count towards the capacity units consumed, between the poll interval.
IPV6 REQUESTS
IPv6 Requests	The total requests received over IPv6, which are also included in the total request count, between the poll interval.
IPV6 DATA PROCESSED
IPv6 Data Processed	The total amount of data processed over IPv6, which is also included in the total data processed, between the poll interval (in MB).

Applications Load Balancer - Errors

Note: Target Control Metrics is mapped under Performance Polling and is disabled by default. To enable or disable metric collection, or to configure the polling interval, navigate to Settings → Performance Polling. Under the Optimize Data Collection tab, select Application Load Balancer as the Monitor Type, choose Target Control Metrics as the Metric Name, and update the required polling status and interval.

Parameter	Description
CONNECTIONS ERRORS
Client TLS Negotiation Errors	The total TLS handshakes that failed between a client and the load balancer, usually a cipher or certificate mismatch on the client, between the poll interval.
Target Connection Errors	The total connections the load balancer could not establish to a target, which points at target health or security group rules rather than at the client, between the poll interval.
Target TLS Negotiation Errors	The total TLS handshakes that failed between the load balancer and a target, usually an expired or untrusted certificate on the target, between the poll interval.
NONCOMPLIANT REQUESTS
Noncompliant Requests	The total requests that do not comply with RFC 7230 and were handled according to the desync mitigation mode, a rise in which can indicate request smuggling attempts, between the poll interval.
LOAD BALANCER HTTP ERRORS
ELB Server Errors	The total HTTP 5XX responses generated by the load balancer itself rather than by a target, between the poll interval.
ELB Client Errors	The total HTTP 4XX responses generated by the load balancer itself rather than by a target, such as malformed requests and requests matching no rule, between the poll interval.
ELB HTTP 3XX Responses	The total HTTP 3XX responses generated by the load balancer itself, typically from a redirect action on a listener rule, between the poll interval.
LOAD BALANCER 5XX ERROR BREAKDOWN
ELB HTTP 502 Errors	The total Bad Gateway responses, returned when a target sends a malformed response or closes the connection before responding, between the poll interval.
ELB HTTP 503 Errors	The total Service Unavailable responses, returned when no healthy target was registered to receive the request, between the poll interval.
ELB HTTP 504 Errors	The total Gateway Timeout responses, returned when a target did not respond before the idle timeout, between the poll interval.
HTTP ACTIONS
Fixed Responses	The total fixed responses returned directly by a listener rule without reaching a target, between the poll interval.
Redirects	The total redirects issued successfully by a listener rule, between the poll interval.
REDIRECT URL LIMIT EXCEEDED
Redirect URL Limit Exceeded	The total redirects that could not be issued because the generated location header exceeded the maximum URL size, between the poll interval.
TARGET CONTROL CHANNELS
Target Control Channel Errors	The total target control channels that failed, between the poll interval.
Target Control Active Channels	The total target control channels open between the load balancer and its targets, at the time of polling.
Target Control New Channels	The total target control channels opened, between the poll interval.
TARGET CONTROL REQUESTS
Target Control Rejected Requests	The total target control requests rejected, typically because the channel limit was reached, between the poll interval.
Target Control Requests	The total requests carried over target control channels, between the poll interval.
TARGET CONTROL WORK QUEUE LENGTH
Target Control Work Queue Length	The total requests waiting in the target control work queue, a growing value meaning the channel path is not keeping up, at the time of polling.
TARGET CONTROL DATA PROCESSED
Target Control Data Processed	The total amount of data carried over target control channels, between the poll interval (in MB).

Applications Load Balancer - Target Groups

Parameter	Description
CONFIGURATION INFO
Target Group	The name of the target group.
Port	The port to use to connect with the target.
Protocol	The protocol to use to connect with the target.
Target type	The type of target that you must specify when registering targets with this target group.
Timeout	The amount of time, in seconds, during which there was no response from the target.
Interval	The approximate amount of time, in seconds, between health checks of an individual target.
Healthy and Unhealthy Hosts - Displays a graphical representation of top 10 target groups, with each target group showing adjacent counts of Healthy and Unhealthy Hosts for comparison.
Target Group Requests - Displays a graphical representation of top 10 target groups based on their Total Requests count.
PERFORMANCE METRICS
Target Group	The name of the target group.
Healthy Hosts	The number of targets that are considered healthy after health checks.
Unhealthy Hosts	The number of targets that are considered unhealthy after health checks.
Average Target Latency	The time elapsed, in seconds, after the request leaves the load balancer until a response from the target is received. This is equivalent to the target_processing_time field in the access logs.
Total Requests	The number of requests processed over IPv4 and IPv6. This count includes only the requests with a response generated by the targets in a specific target group.
Requests Per Target	The average number of requests received by each target in a target group. You must specify the target group using the TargetGroup dimension. This metric does not apply if the target is a Lambda function.
ERRORS
Target Group	The name of the target group.
Target Connection Errors	The number of connections that were not successfully established with the target.
Target TLS Negotiation Errors	The number of TLS connections initiated by the load balancer that did not establish a session with the target.
Target HTTP 5XX Errors	The number of HTTP 5XX server error codes that originate from the load balancer.
Target HTTP 4XX Errors	The number of HTTP 4XX client error codes that originate from the load balancer.
Target HTTP 3XX Errors	The number of HTTP 3XX redirection codes that originate from the load balancer.
Target HTTP 2XX Errors	The number of HTTP response codes generated by the targets.

Applications Load Balancer - Targets

Parameter	Description
TARGET DETAILS
Target ID	The ID of the target. If the target type of the target group is instance, specify an instance ID.
Target Group	The name of the Target Group.
Port	The port on which the target is listening.
Status	The state of the target - initial \| healthy \| unhealthy \| unused \| draining \| unavailable
Reason	Healthy: If the target state is healthy, a reason code is not provided. Initial: If the target state is initial, the reason code can be one of the following values: Elb.RegistrationInProgress - The target is in the process of being registered with the load balancer. Elb.InitialHealthChecking - The load balancer is still sending the target the minimum number of health checks required to determine its health status. Unhealthy: If the target state is unhealthy, the reason code can be one of the following values: Target.ResponseCodeMismatch - The health checks did not return an expected HTTP code. Target.Timeout - The health check requests timed out. Target.FailedHealthChecks - The health checks failed because the connection to the target timed out, the target response was malformed, or the target failed the health check for an unknown reason. Elb.InternalError - The health checks failed due to an internal error. Unused: If the target state is unused, the reason code can be one of the following values: Target.NotRegistered - The target is not registered with the target group. Target.NotInUse - The target group is not used by any load balancer or the target is in an Availability Zone that is not enabled for its load balancer. Target.IpUnusable - The target IP address is reserved for use by a load balancer. Target.InvalidState - The target is in the stopped or terminated state. Draining: If the target state is draining, the reason code can be the following value: Target.DeregistrationInProgress - The target is in the process of being deregistered and the deregistration delay period has not expired. Unavailable: If the target state is unavailable, the reason code can be the following value: Target.HealthCheckDisabled - Health checks are disabled for the target group.

Applications Load Balancer - Configuration

Parameter	Description
CONFIGURATION DETAILS
Load Balancer ID	The ID of the load balancer.
Region	The AWS region in which the load balancer is configured.
State	The state of the load balancer - active \| provisioning \| active_impaired \| failed.
Type	The type of load balancer - application or network.
DNS name	The public DNS name of the load balancer.
Scheme	Internet-facing OR internal. Internet-facing load balancers can route requests from clients over the internet. Internal load balancers can only route requests from clients with access to the VPC for the load balancer.
IP address type	The type of IP addresses used by the subnets for your load balancer.
VPC ID	The ID of the VPC where the load balancer is deployed.
Availability zones	The Availability Zones for the load balancer.
Security groups	The IDs of the security groups for the load balancer.
Creation time	The date and time the load balancer was created.

Network Load Balancer Metrics

Network Load Balancer - Overview

Parameter	Description
TCP CONNECTIONS
Active Connections	The total number of concurrent TCP connections active from clients to the load balancer and from the load balancer to targets.
New Connections	The total number of new TCP connections established from clients to the load balancer and from the load balancer to targets.
TLS CONNECTIONS
Active TLS Connections	The total number of concurrent TLS connections from clients to targets.
New TLS Connections	The total number of new TLS connections established from clients to targets in the time period.
DATA PROCESSED (TCP)
Data processed (TCP)	The total number of bytes processed by the load balancer, in kB.
Data processing rate (TCP)	The rate of bytes processed per minute by the load balancer, in kB/Min.
DATA PROCESSED (TLS)
Data processed (TLS)	The total number of bytes processed by the load balancer, in kB.
Data processing rate (TLS)	The rate of bytes processed per minute by the load balancer, in kB/Min.
CONSUMED LB CAPACITY UNITS
Consumed Capacity Units	The number of load balancer capacity units (LCU) used by your load balancer. You pay for the number of LCUs that you use per hour.

Network Load Balancer - Errors

Parameter	Description
CONNECTIONS ERRORS
Client TLS Negotiation Errors	The total number of TLS handshakes that failed during negotiation between a client and a TLS listener.
Target TLS Negotiation Errors	The total number of TLS handshakes that failed during negotiation between a TLS listener and a target.
RESET PACKETS COUNTERS
Client Reset Packets	The total number of reset (RST) packets sent from a client to a target.
Load Balancer Reset Packets	The total number of reset (RST) packets generated by the load balancer.
Target Reset Packets	The total number of reset (RST) packets sent from a target to a client.

Network Load Balancer - Target Groups

Parameter	Description
Healthy and Unhealthy Hosts - Displays a graphical representation of top 10 target groups, with each target group showing adjacent counts of Healthy and Unhealthy Hosts for comparison.
TARGET GROUPS
Target Group	The name of the target group.
Port	The port to use to connect with the target.
Protocol	The protocol to use to connect with the target.
Target type	The type of target that you must specify when registering targets with this target group.
Timeout	The amount of time, in seconds, during which there was no response from the target.
Interval	The approximate amount of time, in seconds, between health checks of an individual target.
Healthy Hosts	The number of targets that are considered healthy.
Unhealthy Hosts	The number of targets that are considered Unhealthy.

Network Load Balancer - Targets

Parameter	Description
TARGET DETAILS
Target ID	The ID of the target. If the target type of the target group is instance, specify an instance ID.
Target Group	The name of the Target Group to which the target is mapped.
Port	The port on which the target is listening.
Status	The state of the target - initial \| healthy \| unhealthy \| unused \| draining \| unavailable
Reason	Healthy: If the target state is healthy, a reason code is not provided. Initial: If the target state is initial, the reason code can be one of the following values: Elb.RegistrationInProgress - The target is in the process of being registered with the load balancer. Elb.InitialHealthChecking - The load balancer is still sending the target the minimum number of health checks required to determine its health status. Unhealthy: If the target state is unhealthy, the reason code can be one of the following values: Target.ResponseCodeMismatch - The health checks did not return an expected HTTP code. Target.Timeout - The health check requests timed out. Target.FailedHealthChecks - The health checks failed because the connection to the target timed out, the target response was malformed, or the target failed the health check for an unknown reason. Elb.InternalError - The health checks failed due to an internal error. Unused:If the target state is unused, the reason code can be one of the following values: Target.NotRegistered - The target is not registered with the target group. Target.NotInUse - The target group is not used by any load balancer or the target is in an Availability Zone that is not enabled for its load balancer. Target.IpUnusable - The target IP address is reserved for use by a load balancer. Target.InvalidState - The target is in the stopped or terminated state. Draining:If the target state is draining, the reason code can be the following value: Target.DeregistrationInProgress - The target is in the process of being deregistered and the deregistration delay period has not expired. Unavailable:If the target state is unavailable, the reason code can be the following value: Target.HealthCheckDisabled - Health checks are disabled for the target group.

Network Load Balancer - Configuration

Parameter	Description
CONFIGURATION DETAILS
Load Balancer ID	The ID of the load balancer.
Region	The AWS region in which the load balancer is configured.
State	The state of the load balancer - active \| provisioning \| active_impaired \| failed.
Type	The type of load balancer - application or network.
DNS name	The public DNS name of the load balancer.
Scheme	Internet-facing OR internal. Internet-facing load balancers can route requests from clients over the internet. Internal load balancers can only route requests from clients with access to the VPC for the load balancer.
IP address type	The type of IP addresses used by the subnets for your load balancer.
VPC ID	The ID of the VPC where the load balancer is deployed.
Availability zones	The Availability Zones for the load balancer.
Creation time	The date and time the load balancer was created.

Gateway Load Balancer Metrics

Gateway Load Balancer - Performance Overview

Parameter	Description
CONSUMED LB CAPACITY UNITS
Total Consumed LCUs	The total number of load balancer capacity units (LCU) used between the poll interval.
Average Consumed LCUs	The average number of load balancer capacity units (LCU) used between the poll interval.
DATA PROCESSED
Rate of Data Processed	The total number of megabytes processed per minute by the gateway load balancer (excluding health check traffic) between the poll interval (in MB/min).
Data Processed	The total number of megabytes processed by the gateway load balancer (excluding health check traffic) between the poll interval (in MB).
ACTIVE CONNECTIONS
Active Connections	The average number of concurrent connections from clients to targets between the poll interval.
NEW CONNECTIONS
New Connections	The total number of new connections established from clients to targets between the poll interval.
REJECTED CONNECTIONS
Rejected Connections	The average number of rejected connections established from clients to targets between the poll interval.

Gateway Load Balancer - Target Groups

Parameter	Description
TARGET GROUP DETAILS
Resource Name	A substring of the ARN that includes the target group name and target group ID.
Target Type	The type of target - instance \| IP address.
Health Check Status	The current Health Check Status of the target.
Health Check Protocol	The protocols used to perform health checks on targets.
Health Check Port	The port on which the target group listens.
Healthy Threshold	The number of consecutive health checks required for a healthy target.
Unhealthy Threshold	The number of consecutive health checks required for an unhealthy target.
Healthy Hosts	The number of healthy hosts in a target group at the time of polling.
Unhealthy Hosts	The number of unhealthy hosts in a target group at the time of polling.
Health (%)	The health percentage of a target group.
TARGET HEALTH DETAILS
Target ID	The ID of the target.
Target Port	The port on which the target receives traffic.
Health Check Port	The port used for health checks.
Availability Zone	The availability zone where the target is located.
State	The current health state of the target. Possible values: healthy/unhealthy.
Reason	The reason for the current health state.
Description	A detailed description of the health status.

Gateway Load Balancer - Availability Zones

Parameter	Description
AVAILABILITY ZONE DETAILS
Availability Zone	The name of the availability zone.
Active Connections	The average number of concurrent active connections per Availability Zone between the poll interval.
New Connections	The total number of new connections per Availability Zone between the poll interval.
Rejected Connections	The average number of rejected connections per Availability Zone between the poll interval.
Data Processed	The total number of bytes processed per Availability Zone (excluding health check traffic) between the poll interval (in MB).

Gateway Load Balancer - Configuration

Parameter	Description
CONFIGURATION
Load Balancer ID	A substring of the ARN used to uniquely identify the load balancer.
State	The current status of the load balancer - active \| provisioning \| failed.
Type	The type of load balancer.
VPC ID	The ID of the VPC where the load balancer is deployed.
IP address Type	The type of IP addresses used by the load balancer - IPv4 \| dualstack.
Availability Zones	The Availability Zones where the load balancer is deployed.
Creation time	The date and time the load balancer was created.
Deletion Protection	Indicates whether deletion protection is enabled for the load balancer.
Cross Zone Load Balancing	Indicates whether cross zone load balancing is enabled.

Amazon Elastic Load Balancing