Amazon Elastic File System (EFS) is a fully managed, elastic NFS file system that many Linux instances can mount and share at the same time. It grows and shrinks automatically as you add or remove files.
The tell
Whenever multiple Linux EC2 instances need to share the same files concurrently, that’s EFS. EBS attaches to one instance; S3 is object storage. EFS is the shared POSIX file system. For Windows shared files, it’s FSx instead.
Test yourself
Several Linux application servers must access and write to a common set of files simultaneously, with storage that scales automatically. Which service?
- Amazon EBS
- Amazon EFS
- Amazon S3
- EC2 instance store
👉 Click to reveal the answer & explanation
Correct answer: B. EFS is a shared, elastic NFS file system multiple Linux instances mount at once. EBS (A) attaches to a single instance; S3 (C) is object storage, not a mountable file system; instance store (D) is temporary local disk.
Related topics
EBS vs EFS vs S3 · Amazon FSx · Amazon EC2
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