Automated Google Drive Backup with Rclone: Headless OAuth Authentication and systemd Configuration

Introduction: Data Management in AI Development and the Rclone Barrier In AI and LLM (Large Language Model) development environments, data preservation is critical. Training datasets, model checkpoints generated over days of training, and inference logs—these represent the crystallization of engineer wisdom and computational resources. In particular, recent hardware evolution has been remarkable. The NVIDIA RTX 5090 I use in my environment is equipped with a vast 32GB of VRAM. This memory capacity enables fine-tuning of massive models and efficient training with increased batch sizes. However, as VRAM increases, both the model sizes and data volumes handled bloat. Local server SSDs deplete easily, constantly posing the risk of training halts due to insufficient disk space. This is where backing up data to Google Drive or S3-compatible object storage becomes useful. Rclone is a highly powerful tool for cloud storage integration, but the authentication flow on a headless server lacking a