Hybrid fits when you have legacy on-prem or colo and want cloud for burst or new apps. Use VPN or dedicated links between environments. Manage identity and config across both; watch egress and complexity.
When hybrid makes sense
- Legacy: Existing systems in on-prem or colo that are costly or risky to move immediately. Keep them there; use cloud for new apps or burst.
- Burst: Run baseline in colo or on-prem; scale out to cloud for peaks (e.g. events, campaigns). Reduces fixed cost while handling spikes.
- Data gravity: Keep large or sensitive datasets in one place; run compute in cloud when needed (e.g. analytics, ML) and pull data over secure links.
Connectivity
- VPN: Encrypted tunnel over the internet between your network and the cloud VPC. Lower cost; good for moderate traffic. Latency and throughput depend on internet path.
- Dedicated link: Direct Connect, ExpressRoute, or similar. Predictable latency and higher throughput; higher cost. Use when you need stable, high-bandwidth connectivity.
- Security: Treat the link as untrusted or trusted depending on sensitivity. Use encryption and access control on both sides.
Consistency and ops
- Identity: Federate identity (e.g. SSO, SAML) so users and apps can access both environments with one login. Avoid duplicate user stores.
- Config and automation: Use the same tooling (Terraform, Ansible) where possible so config is consistent. Different APIs and features per environment add complexity.
- Egress: Data leaving the cloud (and sometimes entering) can incur cost. Monitor egress and optimize (compress, cache, keep hot data in cloud if apps are there).
Summary
Hybrid = on-prem/colo + cloud. Use when you have legacy or need burst. Connect with VPN or dedicated link; manage identity and config across both; watch egress and complexity.
