From 5edafa05ca3a3771b2adc7277f43d8af956b1dfb Mon Sep 17 00:00:00 2001 From: Magnus Kulke Date: Wed, 12 Oct 2016 01:00:19 +0200 Subject: [PATCH 1/2] Added ALB Gotcha about unhealthy targets --- README.md | 1 + 1 file changed, 1 insertion(+) diff --git a/README.md b/README.md index 94dbacee..70349ade 100644 --- a/README.md +++ b/README.md @@ -879,6 +879,7 @@ ALB - ALBs do not (yet) support routing based on HTTP “Host” header or HTTP verb. - Instances in the ALB's target groups have to either have a single, fixed healthcheck port (“EC2 instance”-level healthcheck) or the healthcheck port for a target has to be the same as its application port (“Application instance”-level healthcheck) - you can't configure a per-target healthcheck port that is different than the application port. - ALBs are VPC-only (they are not available in EC2 Classic) +- In a target group, if there is no healthy target, all requests are routed to all targets. An example: you add a target group containing a single service (with a long init phase maybe) as target to a listener, it does not pass health checks (yet), requests will still reach your (initializing) service. Elastic IPs ----------- From 80d80b3fb332e1ff17dc767d929194e98dd0beb6 Mon Sep 17 00:00:00 2001 From: Magnus Kulke Date: Wed, 12 Oct 2016 01:11:55 +0200 Subject: [PATCH 2/2] Addressed review comments. --- README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/README.md b/README.md index 70349ade..fd6dfcb5 100644 --- a/README.md +++ b/README.md @@ -879,7 +879,7 @@ ALB - ALBs do not (yet) support routing based on HTTP “Host” header or HTTP verb. - Instances in the ALB's target groups have to either have a single, fixed healthcheck port (“EC2 instance”-level healthcheck) or the healthcheck port for a target has to be the same as its application port (“Application instance”-level healthcheck) - you can't configure a per-target healthcheck port that is different than the application port. - ALBs are VPC-only (they are not available in EC2 Classic) -- In a target group, if there is no healthy target, all requests are routed to all targets. An example: you add a target group containing a single service (with a long init phase maybe) as target to a listener, it does not pass health checks (yet), requests will still reach your (initializing) service. +- In a target group, if there is no healthy target, all requests are routed to all targets. For example, if you point a listener at a target group containing a single service that has a long initialization phase (during which the health checks would fail), requests will reach the service while it is still starting up. Elastic IPs -----------