AWSAWS Storage GatewayStorage

`aws_storagegateway_gateway` cost estimation

Hybrid storage bridging on-premises to AWS. File Gateway ($0.023/GB-month + data transfer), Volume Gateway (per-GB cached or stored mode), Tape Gateway (VTL for backup). Pricing varies significantly by gateway type.

AWS Storage Gateway provides hybrid cloud storage with multiple gateway types for different use cases. The aws_storagegateway_gateway resource creates the gateway; specific shares/volumes/tapes are configured as separate resources. Pricing varies dramatically by gateway type.

File Gateway: SMB/NFS access to S3 buckets from on-prem. Pricing: - $0.023/GB-month stored in S3 (Standard tier; lifecycle to cheaper tiers possible) - Data transfer out from AWS at standard rates - Optional Audit logs at CloudWatch rates

Volume Gateway has two modes: - Cached: hot data cached on-prem, cold in AWS. $0.023/GB-month for S3 storage - Stored: full copy on-prem, async sync to AWS. $0.023/GB-month for S3 backup

Tape Gateway (VTL): replaces physical tape backup with virtual tapes in S3 Glacier: - $0.023/GB-month for S3 storage of active tapes - $0.0036/GB-month for archived (Glacier Deep Archive equivalent) - $0.10 per retrieval request from archive

Common cost surprise: data transfer out. Pulling 1 TB back from File Gateway to on-prem = $0.09/GB × 1024 = $92 in transfer. For frequent download patterns, the transfer cost can exceed storage cost.

c3x estimates Storage Gateway based on gateway_type and the storage configured. For data transfer volume, specify in c3x-usage.yml.

Terraform example

A minimal but realistic configuration that C3X can estimate.

resource "aws_storagegateway_gateway" "files" {
  gateway_ip_address  = "10.0.0.100"
  gateway_name        = "on-prem-file-gw"
  gateway_timezone    = "GMT-5:00"
  gateway_type        = "FILE_S3"
  smb_active_directory_settings {
    domain_name = "corp.example.com"
    password    = var.ad_password
    username    = "smbadmin"
  }
}

resource "aws_storagegateway_nfs_file_share" "share" {
  client_list  = ["10.0.0.0/24"]
  gateway_arn  = aws_storagegateway_gateway.files.arn
  location_arn = aws_s3_bucket.files.arn
  role_arn     = aws_iam_role.gateway.arn

  cache_attributes {
    cache_stale_timeout_in_seconds = 300
  }
}

Pricing dimensions

What you actually pay for when you provision aws_storagegateway_gateway.

Dimension	Unit	What's being charged
S3 storage (File/Volume Gateway)	per GB-month	Storage in S3 for data accessed via the gateway. Subject to lifecycle policies for tiering. $0.023/GB-month (S3 Standard)
Tape Gateway storage	per GB-month	Active tapes in S3; archived tapes in Glacier Deep Archive. $0.023/GB active, $0.0036/GB archived
Data transfer out	per GB	Transfer from AWS back to on-prem. Standard data transfer rates apply. $0.09/GB tier 1
Gateway requests	per million	S3 API requests generated by gateway operations. Typically small compared to storage. $0.005 per 1K PUTs
Tape retrieval from archive	per request	Restoring archived tape contents from Glacier Deep Archive. $0.10 per retrieval

Optimization tips

Common ways to reduce aws_storagegateway_gateway cost without changing the workload.

Use lifecycle policies on backing S3 bucket

50-85% on cold data

File Gateway stores in S3 Standard by default. For cold data, lifecycle to S3 IA ($0.0125/GB-month) or Glacier ($0.004/GB-month). Saves 50-85% on storage. Carefully consider retrieval needs.

Audit data transfer patterns

If transfer out exceeds storage cost, your access pattern doesn't fit the hybrid model. Consider VPN to S3 for direct access, or keep frequently-accessed data on-prem.

Right-size local cache for Volume Cached mode

Cached Volume Gateway keeps recently-accessed blocks on-prem. Too small cache = frequent S3 fetches (high data transfer cost). Too large = wasted on-prem hardware. Monitor cache hit rate; size to ~95% hit rate.

Use Tape Gateway for compliance backup

Variable, often 80%+

For backups required by regulation but rarely accessed, Tape Gateway with Glacier Deep Archive is dramatically cheaper than maintaining physical tape libraries ($0.0036/GB-month vs ~$50K+/year for tape hardware/personnel).

FAQ

Is Storage Gateway worth it vs direct S3?

If on-prem applications need SMB/NFS access (legacy apps, Windows file shares, video editing workflows), yes — Storage Gateway provides standard file protocols on top of S3. For applications that can natively use S3 SDK, direct S3 is simpler and cheaper (no gateway hardware/VM to maintain).

How much does the on-prem gateway cost?

The gateway software is free; you provide the hardware. AWS provides downloadable VM images for VMware/Hyper-V, AMI for EC2 deployment, or hardware appliance ($5-20K+). The S3 storage and transfer fees are the ongoing costs.

Can I use Storage Gateway for backup specifically?

Yes, Tape Gateway is purpose-built for replacing tape backup workflows. Legacy backup software (Veeam, Veritas, etc.) writes to virtual tapes that get archived to Glacier Deep Archive. Often cheaper than maintaining tape infrastructure.

What's the latency impact?

File Gateway caches recently accessed files locally — first access pulls from S3 (slower), subsequent reads from cache (fast). Latency to S3 depends on network. For latency-sensitive workloads, ensure adequate cache size and consider Direct Connect for predictable network performance.