Overview

LNet is a virtual networking layer which allows Lustre nodes to communicate with each other.

System Diagram

• lnetctl: User space utility used to configure and query LNet kernel module
• DLC Library: User space library which communicates with LNet kernel module primarily via IOCTL
• LNet IOCTL: Module which handles the IOCTLs and calls appropriate callbacks in the LNet kernel module
• PTLRPC: Kernel module which implements an RPC protocol. It's the primary user of LNet.
• LNet: Kernel module which implements the Lustre Networking communication protocol
• o2iblnd: Verbs driver. It executes RDMA operations via verbs
• socklnd: TCP/IP driver. It sends/receives TCP messages
• gnilnd: Cray/HPE driver not maintained by us

LNet Block Level Diagram

The diagram above represents the different functional blocks in LNet. A quick overview will help in understanding the code

• When LNet starts up it reads various module parameters and configures itself based on these values
• Further configuration can be added dynamically via lnetctl utility
• The main

Useful Documentation

Presentations

Tasks