Quiz Entry - updated: 2026.10.15
Some DevOps practitioners distinguish blue/green from red/black deployment. What is the difference?
In this distinction, blue/green moves traffic over gradually, so both systems serve users for a while, whereas red/black switches all traffic at once.
* In this distinction blue/green shifts traffic gradually so both versions serve users for a while; red/black switches everything at once. *
Both strategies use two identical environments. They differ in how the switch happens:
| Blue/green (in this distinction) | Red/black | |
|---|---|---|
| Traffic switch | Gradual, step by step | All at once |
| Both versions live at the same time? | Yes, for a period | No |
| Effect | Problems surface on part of the traffic first | Clean cut, every user on exactly one version |
Many people use the two names as synonyms, which is why this is only a distinction some practitioners make. Netflix's deployment tool Spinnaker long called its all-at-once switch "red/black"; in 2023 its documentation renamed it to blue/green.