Questions tagged with Availability

Hi, I have an environment on Elastic Beanstalk with Application Load Balancer listen to HTTPS and HTTP as well, we also have a auto scaling group with 6 to 10max instances. The application is facing an issue that we're struggling to find, a segfault (we're on it) once it happens in an instance it get terminated and start a new ok. However during the instance replacement, the state of the enviroment becomes "Severe" and the application get off, stops responding. We're looking for a solution for high availability, if we have 4 instances running and one requires to be terminated for some reason, shouldn't the balancer keep the enviroment live and available? What should we look for to have it in place?lg...

I created an instance from an image that I had created from a snapshot. The original image is t4g.large, however, when creating an instance from this image I was able to only create t3.large (the option for t4g.large was greyed out). The instance creation went fine but now I am not able to connect to my instance. Under the Status Check I see "Instance reachability check failed. Check failure at 2023/01/13 15:58 GMT+5:30 (10 minutes)" Availability zone is us-west-2d. Any inputs on this would be highly appreciated.lg...

I am trying to attach a new volume to an ec2 instance but not able to view all my volumes, i even put all the volumes in same availability zone still not able to find all. Because of this i am not able to perform detach and attach a new volume to the instance. Enter image description here](/media/postImages/original/IM-IZYBbwFQdSFJnMCZe49Yw)lg...

We have an ASG with 100+ hosts in us-east-1, that is distributed across all 6 Availability Zones. This ASG is added as a target group to our Network Load Balancer which is also enabled in all 6 AZs. Currently, we have Cross-Zone Load Balancing enabled in our NLB, which distributes the incoming traffic to all the hosts across all AZs equally. But, this cross-zone load balancing is adding a significant cost to our monthly bills. All our clients connect to our service through VPC peering (private links) and all these clients are also distributed equally across all AZs. From a networking stand point, we don't see a necessity to enable cross-zone load balancing and so we are planning to turn this feature off in our prod environments. We went through the following AWS docs ([1](https://docs.aws.amazon.com/autoscaling/ec2/userguide/ec2-auto-scaling-termination-policies.html?icmpid=docs_ec2as_help_panel)) & ([2](https://docs.aws.amazon.com/autoscaling/ec2/userguide/auto-scaling-benefits.html)), and understood that EC2 ASGs by default, will try to maintain an equivalent number of hosts across all AZs to the maximum extent, while adding hosts to ASGs or when a scale-in event occurs. We would like to understand how the following scenario would work with cross-zone load balancing disabled and if it poses any availability risk to our service. We use "In-Place" deployment type in our CodeDeploy's deployment groups. While hosts are being de-registered from NLB during in-place deployments, will CodeDeploy ensure that hosts are taken down evenly across all AZs? [Our deployment configuration makes sure that at-least 70% of the hosts are healthy during the course of deployment. Could there be a case where CodeDeploy takes down more number of hosts (or all 30% of hosts) from a single AZ, putting the availability of NLB node in that AZ at risk (since cross-zone routing is turned-off)?]lg...

We are trying to load balance our web servers behind an ALB. However, we can't find the private ip for the ALB. Right now, our provider NAT's (providers hard requirement) all addresses directly to our web server. We would like to put an ALB in front of it so that we can load balance web servers. Current Solution: NAT --> Web Server Targeted Solution NAT --> ALB --> Web Server x3lg...

I'm trying to migrate a PostgresQL 10 RDS DB to version 14. No matter which instance type I try, it says that it's not available in our availability zone (us-east-1a). Types we've tried: db.r6g.large db.r6i.large db.r5.large db.t4g.xlarge db.t3.xlarge db.r5b.large db.m6g.xlarge db.x2g.large db.m6i.xlarge What can we do? Best Regards, Ortwinlg...

What happens to the EC2 Instance state (ex: stopped, pending, terminated), when an Availability Zone failure occurs where the EC2 instance was launched.lg...

How does AWS ensure that spikes from Amazon.com (e.g. during Black Friday) do not affect performance for other customers? Are there any specific measures in place?lg...

Hi, I'm pretty new to AWS. We deployed our node.js app to Elasticbeanstalk, while creating Postgres database on RDS. So all worked fine for few weeks and since yesterday, I suddenly cannot access the service. It does not response. I tried looking at logs on Elasticbeanstalk but it's empty after December 1st. In Chrome Network inspect, it just says: `Failed to load response data. Resource with given identifier does not exist`. We were using free tier. I am sure something happened with the start of new month, but don't know what. I guess our plan expired or something like that. Also, I've tried accessing the environment using ssh (with valid .pem file, it worked before). However, now it says Permission defined What could be an issue here? Thanks in advancelg...

As of now, I have been using Lightsail-related computing business for several months, but I have found that sometimes my customers cannot connect to the server in recent months, and this time lasts for a short time, and it will be restored in a few minutes. Still, it makes me worry about its usability. After my investigation, when my client can't access the server, he can't ping the target IP address. Does this explain the difference in the availability of EC2 and Lightsail? Or is it an issue with the AWS network? If my business requires high availability of the network, will using more expensive EC2 improve availability?lg...

The Client VPN examples at https://aws.amazon.com/blogs/networking-and-content-delivery/using-aws-client-vpn-to-scale-your-work-from-home-capacity/ use this as an example for a failover (?) setup between two AZs:  Is that enough to ensure connectivity between "remote workers" and VPC B/C/D in case of a problem in AZ A or AZ B? Is there any way I could realistically simulate a failure of one AZ? I have the recommended setup for TGW attachments in their own /28. My AZ A and AZ B in this case are not the subnets with the TGW attachment, because the CVPN endpoint doesn't allow association with a subnet smaller than /27 - would it be a better/worse idea or make any difference at all if I used /27 subnets for the TGW attachments so I could associate the CVPN endpoints with the same subnets? Thanks, Marclg...

Hi all, Is it possible to check the availability of specific types of ec2 by availability zone? Best regards.lg...