James's Ramblings

AWS: EFS

Created: October 04, 2020

  • EFS requires endpoints created within a VPC. The endpoints are called mount targets.

  • Mount targets are identified by their mount target ID.

  • Mount targets appear inside subnets and have both a DNS name and an IP address.

  • The EFS file system’s DNS name resolves to a mount target’s IP address.

  • 1000s of instances can connect to a single EFS file system.

  • Instances in other VPCs can be connected via VPC Peering.

  • On-premise clients can connect using a VPC or Direct Connect connection.

  • Automatic backups are enabled by default and use AWS Backup.

  • Lifecycle management moves files that have not been accessed for a period of time to the EFS Infrequent Access Storage class.

Performance

  • Two performance modes: general purpose and max I/O. This is configured at ESF file system creation.

  • Two throughput modes:

    • Bursting: throughput scales with the file system size.
    • Provisioned: a fixed level of throughput.
    • This is configured at ESF file system creation.

Encryption

  • EFS has encryption at rest and encrption in transit capabilities.
  • Encryption at rest is enabled by default.
  • KMS manages encryption keys.
  • Custom KMS keys can be used. If they are not used, the default key is used.
  • Encryption at rest and encryption in transit can be configured separately or together.

Access control

  • Administration of EFS can be controlled via used-based or resource-based IAM policies.
  • NFS clients access to file systems can be controlled via resource-based IAM policies.
  • The standard POSIX and NFS permissions also apply.

Monitoring

File system level (with the EFS dashboard):

  • Throughput utilization.
  • IOPS by type.
  • Throughput by type.
  • Average IO size (KiB).
  • Percent IO limit.
  • Client connections.

CloudWatch:

  • Client Connections Sum.
  • Data Read IO Bytes Average.
  • Data Write IO Bytes Average.
  • Burst Credit Balance Average.
  • Percent IO Limit Average.
  • Permitted Throughput Average.

Available Metrics:

  • ClientConnections.
  • MetadataIOBytes.
  • TotalIOBytes.
  • BurstCreditBalance.
  • PermittedThroughput.
  • PercentIOLimit.
  • BurstCreditBalance.
  • PercentIOLimit.
  • PermittedThroguhput.