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While this loads — worth knowing
ElastiCache RedisnotElastiCache Memcached
Redis has data structures — sorted sets, counters, pub/sub. Memcached has plain keys and nothing else.
Loading…
While this loads — worth knowing
Redis has data structures — sorted sets, counters, pub/sub. Memcached has plain keys and nothing else.
A shared NFS file system that grows and shrinks by itself, mounted at once by many instances, containers and functions across the zones of a Region.
Where EFS takes you6 steps, all open
Amazon EFS is a file system you never size or manage. It grows and shrinks as files are added and removed, and many clients mount it at once over NFS: EC2 instances, containers on ECS, EKS and Fargate, and Lambda functions.
Regional or One Zone. A Regional file system, the kind AWS recommends, stores data across several Availability Zones and stays available when a zone is not. A One Zone file system keeps it in one zone, where losing the zone could lose the data. It works with Linux, not Windows.
The shared drive in an office: everyone on every floor sees the same folders, it never fills up, and you pay for what is on it. Each floor has its own socket to plug into. Files nobody has opened for a while move to a cheaper cabinet by themselves.
EFS file systemMount targetNFSv4.1Infrequent AccessArchiveRegional or One ZoneA mount target in every zone the instances use. An instance that mounts through a mount target in another zone pays for data access across zones; access within the same zone is free.
A replica to fail over to. Replication keeps a copy in another Region, or the same one, and for most file systems changes reach it within 15 minutes.
Regional file system, a mount target in each zone
InstancesServed by Mount target a
InstancesServed by Mount target b
Click a node to make it fail.
One Zone file system in AZ a
InstancesServed by Mount target a
InstancesServed by Mount target a
Click a node to make it fail.
Regional survives a zone. Instances in the zones that are still up keep reading and writing through their own mount targets. Only the instances in the lost zone go with it.
One Zone depends on one zone. Every instance goes through that zone's single mount target, the ones in other zones paying for access across zones. Losing the zone cuts all of them off, and the data itself could be lost, so back it up or replicate it.
Encrypt at rest when you create it. Encryption at rest is chosen when the file system is created, and then covers all its data and metadata.
Encrypt in transit when you mount it. Encryption of data in transit is turned on as the file system is mounted.
Two layers of access. IAM policies and network controls, such as the mount targets' security groups, decide which NFS clients can connect. POSIX permissions decide what they can do with each file.
Only root at first. On a new file system, only the root user on an instance can read, write and run files until you grant permissions.
Storage used, not provisioned, per GB-month, lowest in Archive and highest in Standard.
Access charges for reads, writes and moving files between classes. With Elastic throughput you pay only for the throughput you use; Provisioned throughput is charged for what you set above the baseline your Standard storage includes.
Across zones. Access from another zone is charged as data transfer; from the same zone it is free.
Lifecycle saves the most on files that go unread: to Infrequent Access after 30 days and to Archive after 90, by default.
Prices change, so none are printed here. Check the EFS pricing page on aws.amazon.com.
| Storage | Kind | Used by | Where it lives | Choose it when |
|---|---|---|---|---|
| EFS | File system over NFS | Many Linux clients at once | A Region, or one zone | Shared files for instances, containers and functions |
| EBS | Block volume | One instance, or up to 16 with Multi-Attach | One Availability Zone | A disk for one instance, such as a database's |
| S3 | Objects over HTTP | Any number of clients | A Region | Any amount of objects, websites and data lakes |
| Instance store | Block storage on the host | Its own instance only | The instance's host | Scratch data that can be lost |
| Throughput mode | How it scales | Choose it when |
|---|---|---|
| Elastic | Up and down with the workload; you pay for what you use | Spiky or unpredictable load: the default |
| Provisioned | A level you set, whatever the size | Known needs, with average load at 5 percent of peak or more |
| Bursting | With the amount in Standard storage, plus burst credits | Throughput should grow with what is stored |
instances in several Availability Zones must share the same filesAn EFS Regional file system
Each zone gets a mount target, and the data is stored across zones.
a shared file system for Windows serversNot EFS
EFS does not support Windows instances.
the file system must grow without anyone resizing itEFS
It grows and shrinks as files are added and removed.
cut the cost of files nobody has opened for a monthLifecycle management to Infrequent Access
Files unread in Standard for 30 days move there by default.
spiky, unpredictable throughputElastic throughput
It scales with the workload, and you pay only for what you use.
Max I/O performance mode, for more parallel clientsGeneral Purpose, almost always
Max I/O is the previous generation, with higher latency. AWS recommends General Purpose.
instances mount through a mount target in another zoneAdd a mount target in their own zone
Access across zones is charged; within a zone it is free.
a copy of the file system in another Region for disaster recoveryEFS Replication
For most file systems, changes reach the replica within 15 minutes.
turn on encryption at rest for an existing file systemCreate a new, encrypted file system
Encryption at rest is chosen when a file system is created.
A company runs a content management system on Linux EC2 instances in an Auto Scaling group across three Availability Zones. Files uploaded through any instance must be visible to all of them at once. The storage must survive the loss of a zone and grow without anyone resizing it. What should a solutions architect use?
Linux web servers in an Auto Scaling group across three zones must all read and write the same uploaded files at once, as an ordinary file system. The storage must grow by itself and stay available if a zone fails. What do the web servers mount?
30 days, Archive after 90.15 minutes.This whole page is free right now.The AWS library is still being written, so every page of it is open to everyone while that lasts. It becomes a paid bundle later; what you read today costs you nothing.
Every fact on this page was checked against AWS’s own documentation on 15 Sept 2026. If AWS has changed something since, its page is the one to trust.