{"id":79,"date":"2010-01-27T05:36:50","date_gmt":"2010-01-27T10:36:50","guid":{"rendered":"http:\/\/migrate2cloud.com\/blog\/?p=79"},"modified":"2016-03-21T02:52:55","modified_gmt":"2016-03-21T07:52:55","slug":"quick-start-with-elastic-load-balancer-elb","status":"publish","type":"post","link":"https:\/\/www.migrate2cloud.com\/blog\/quick-start-with-elastic-load-balancer-elb\/","title":{"rendered":"Quick start with Elastic Load Balancer (ELB ) on EC2"},"content":{"rendered":"

Elastic Load Balancing ( ELB ) is an AWS load balancer service that is readily available for users who have signed up for AWS EC2 and s3 services . ELB is configured to automatically distribute incoming application traffic across multiple Amazon EC2 instances . Recently AWS has announced<\/a> support for ELB to the AWS Management Console which will give users a simple, point-and-click web interface to create and configure load balancers for the AWS EC2 instances .<\/p>\n

Below are the simple steps to configure ELB for webserver from the command line .<\/p>\n

1 ) Setting up the tools<\/strong><\/p>\n

Download the ELB API Tool<\/a> and set the environmental variables<\/p>\n

[bash]export JAVA_HOME=\/path\/to\/java
\nexport EC2_PRIVATE_KEY=\/path\/to\/key
\nexport EC2_CERT=\/path\/to\/cert
\nexport AWS_ELB_HOME=\/path\/to\/ELB-API-TOOLS
\nexport PATH=$PATH:$AWS_ELB_HOME\/bin[\/bash]<\/p>\n

2 ) Create an HTTP Load Balancer<\/strong><\/p>\n

[bash]elb-create-lb LoadBalancerName \u2013headers \u2013listener \u201clb-port=80,
\ninstance-port=80,protocol=http\u201d \u2013availability-zones us-east-1a[\/bash]<\/p>\n

3 ) Register Instances with ELB<\/strong><\/p>\n

[bash]elb-register-instances-with-lb LoadBalancerName \u2013headers \u2013instances
\ni-11111111,i-22222222[\/bash]<\/p>\n

4 ) Configure DNS<\/strong><\/p>\n

since ELB does not work on the root of a domain , you have to redirect it to www and set CNAME for www as the ELB DNS name . So set domain forwarding for root domain to www and set CNAME for www in the DNS management portal .<\/p>\n

[bash]<\/p>\n

TYPE CNAME
\nTTL 5
\nNAME WWW
\nVALUE DNS-NAME-OF-ELB<\/p>\n

[\/bash]<\/p>\n

5 ) Configure Health Check<\/strong><\/p>\n

check the health of the instances registered with ELB .<\/p>\n

i)Configure a TCP healthcheck with target port 8080<\/strong><\/p>\n

[bash]elb-configure-healthcheck LoadBalancerName \u2013headers
\n\u2013target \u201cTCP:8080\u2033 \u2013interval 5 \u2013timeout 3 \u2013unhealthy-threshold 2
\n\u2013healthy-threshold 2[\/bash]<\/p>\n

ii) Configure an HTTP healthcheck with target port 80 with a path<\/strong><\/p>\n

[bash]elb-configure-healthcheck LoadBalancerName \u2013headers
\n\u2013target \u201cHTTP:80\/status\u201d \u2013interval 5 \u2013timeout 3
\n\u2013unhealthy-threshold 2 \u2013healthy-threshold 2[\/bash]<\/p>\n

6 ) check the ELB and instance Health <\/strong><\/p>\n

i ) Describe the state of all instances for LoadBalancer \u201cLoadBalancerName\u201d<\/strong><\/p>\n

[bash]elb-describe-instance-health LoadBalancerName \u2013headers[\/bash]<\/p>\n

ii ) Describe the state of specific instances for LoadBalancer <\/strong><\/p>\n

[bash] elb-describe-instance-health LoadBalancerName \u2013headers
\n\u2013instances i-11111111 , i-22222222 [\/bash]<\/p>\n

7 ) Deregistering instances from ELB<\/strong><\/p>\n

[bash]elb-deregister-instances-from-lb LoadBalancerName \u2013headers
\n\u2013instances i-11111111,i-22222222 [\/bash]<\/p>\n

8 ) Expand a Load Balanced Application to an Additional Availability Zone<\/strong><\/p>\n

Suppose that you have 2 ec2 instances ( i-11111111 and i-22222222 ) running in the availability zone us-east-1a is registered with an ELB . You want to register 2 more ec2 instances ( i-33333333 and i-44444444 ) present in the availability zone us-east-1b with the same ELB .<\/p>\n

i ) Register the new instances ( i-33333333 and i-44444444 ) that are in the new zone ( us-east-1b ) with the load balancer<\/strong><\/p>\n

[bash] elb-register-instances-with-lb LoadBalancerName \u2013headers
\n\u2013instances i-33333333 , i-44444444 [\/bash]<\/p>\n

ii ) Enable the new zone for the Load Balancer. <\/strong><\/p>\n

[bash]elb-enable-zones-for-lb LoadBalancerName \u2013headers
\n\u2013availability-zones us-east-1b [\/bash]<\/p>\n

9 ) Disable an Availability Zone from a Load Balanced Application<\/strong><\/p>\n

[bash]elb-disable-zones-for-lb LoadBalancerName \u2013headers
\n\u2013availability-zones us-east-1a [\/bash]<\/p>\n

[bash]elb-deregister-instances-from-lb MyLoadBalancer \u2013headers
\n\u2013instances i-11111111 , i-22222222[\/bash]<\/p>\n

10 ) Tear Down an Existing LoadBalancer<\/strong><\/p>\n

[bash] elb-delete-lb MyLoadBalancer [\/bash]<\/p>\n","protected":false},"excerpt":{"rendered":"

Elastic Load Balancing ( ELB ) is an AWS load balancer service that is readily available for users who have signed up for AWS EC2 and s3 services . ELB is configured to automatically distribute incoming application traffic across multiple Amazon EC2 instances . Recently AWS has announced support for ELB to the AWS Management […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[3],"tags":[235,221,604,329,22,127,215,243,144,137,238,6,624,116,444,44,625,626,234,233],"class_list":["post-79","post","type-post","status-publish","format-standard","hentry","category-cloud-computing","tag-amazon-elastic-compute-cloud","tag-amazon-web-services","tag-amazon-com","tag-api","tag-aws-ec2-cloud-computing-elb-http-load-balancer-amazon","tag-cloud-computing","tag-cloud-infrastructure","tag-company-product","tag-company-amazon-com","tag-department-stores-nec","tag-dns","tag-ec2","tag-eucalyptus","tag-http","tag-java","tag-load-balancing","tag-point-and-click-web-interface","tag-s3-services","tag-web-hosting","tag-web-services"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t