Questions[amazon-vpc](server)

According to Amazon and my test, a /24 VPC subnet allows for 251 available IP addresses. I have 2 other subnets in that VPC that appear to have no IP's in use by EC2 and the available IPs field indicates that there are only 250 available. I have checked

I am trying to figure out which resources are using those IP's but it seems AWS does not allow for that kind of query.

What I would like to see is a list of resources that are using IP's for a specific VPC subnet.

If anyone can shed some light as to what AWS services can use subnet IP's except for EC2 that would also help.

Thanks.

I added a VPC endpoint to my VPC using CloudFormation, and allowed s3 usage. The routes are visible in the AWS console, but not in the local routing tables of the EC2 instances:

$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         172.29.4.129    0.0.0.0         UG    0      0        0 eth0
169.254.169.254 0.0.0.0         255.255.255.255 UH    0      0        0 eth0
172.29.4.128    0.0.0.0         255.255.255.128 U     0      0        0 eth0

How do I verify that the EC2 instances in the VPC actually uses the VPC endpoint for S3, and not the available internet connection?

I have a server that is outside of AWS. I'd like to be able to mount an EFS volume to it, but I am not sure if that is possible.

Perhaps if you create a VPC, and you create a tunnel over VPN?

Does anybody know if this is possible?

Recently apple has imposed IPv6 support as mandatory for all its vendors who use its mobile-api and aws vpc doesn't provide IPv6 support. How can I achieve this. I have checked https://aws.amazon.com/blogs/aws/elastic-load-balancing-ipv6-zone-apex-support-additional-security/ however I am not sure what to do.

I would need expert advise here.

I have been creating AWS VPCs and I am wondering if there is a recommended CIDR value when creating VPCs. What are the factors that I must consider when choosing a CIDR and does the CIDR value affect the performance of the network?