In the context of hardware testing, integration, and buildout, L10, L11, and L12 refer to different levels of manufacturing and assembly processes:
- L10: This level involves the server-level assembly. The result of L10 is a fully working server that can fully boot into an OS.
- L11: This level involves rack-level assembly. The result of L11 is a full rack with all of the intra-rack components cabled up. This might include top-of-rack switches, cabling, and PDUs.
- L12: This level involves cluster-level assembly. The result of L12 is a full cluster, complete with cross-rack cabling.
These levels help define clear handoffs between the manufacturing and deployment processes to ensure that each stage is thoroughly tested and validated before moving on to the next. It should prevent misconfigurations or problems in low-level manufacturing are caught early.