I am using "m5d.8xlarge" ec2 instance, which comes ready with 2*600G SSD Volumes, directly attached. They are appearing on the OS, however no mention on the console, as I can't retrieve any info about them.
And it is showing as well the serial of the volumes as AWS-*** not as normal EBS volumes vol***.
I read that these are ephemeral or something; I want to have any AWS official docs that thoroughly explain how this local storage works, as we are hosting prod workload on it, appreciate if someone can explain or provide docs.
CodePudding user response：
"m5d.8xlarge" ec2 instances comes with 2 ephimeral storage which are instance store volume.
Instance store volumes (docs) are directly attached to underlying hardware to reduce latency and increase IOPS and data throughput.
However there is a caveat, if you ec2 instance is terminated,stops, hibernated or stopped or underlying hardware gets shutdown due to some glitch all the data stored on on these ephemeral storage will be lost. Generally instance store volumes are used for buffer,cache.
In order to confirm you can follow this https://aws.amazon.com/premiumsupport/knowledge-center/ec2-linux-instance-store-volumes/ :-
- ssh into ec2 instance
- install nvme-cli tool ->
sudo yum instal nvme-cli sudo nvme list- to list all instance store volumes
if you want data to persist you should go for EBS or EFS
In short If you want to access data with super low latency and you can afford to loose data go for instance store but if it is business critical data for example database workload go for EBS, YOu can still achieve very high IOPS and throughput using IO1,IO2 volume types or if you have a want to go even further use nitro ec2 instance type which gives maximum 64000 IOPS.
Play with EBS volume types to increase IOPS and throughput https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-volume-types.html