SlurmDroid

A native Android app for monitoring and controlling a Slurm HPC cluster from your phone, with a plugin system for additional server tools.

Important

The app has until now only been tested for the HPC-Cluster of the universities of the state of Baden-Württemberg (Germany)

Please consider testing it against other clusters and file an issue if you encounter any problems!

Features

Slurm

• Live job monitoring — active jobs with state, partition, time used/limit, and a progress bar for running jobs
• Swipe to cancel — swipe a job left to cancel it with a confirmation dialog
• Submit jobs — submit new jobs via an inline command or by selecting a .slurm script file from the server; configure partition, nodes, CPUs, memory, GPUs, time limit, and optional script arguments
• Job history — past jobs grouped by date with one-tap re-submit; Slurm array jobs are grouped under their parent with all array tasks listed and individually navigable
• Re-submit any job — jobs submitted outside the app are also captured (via scontrol) and can be re-submitted from the history screen
• Job details — per-job screen showing timing, resources, live sstat metrics (running jobs), exit code, and the sbatch command used to submit the job; array parent jobs list all tasks inline
• Log viewer — browse and read .log/.err files from a configurable log directory directly in the app
• Cluster dashboard — collapsible partition table showing node availability and CPU load per partition, color-coded green/yellow/red
• Notifications — persistent notification while a job is running (tap to open job details); replaced by a success or error notification when the job finishes; can be disabled in Settings
• Auto-polling — refreshes every 10 s with a countdown spinner in the toolbar; pull-to-refresh available on every screen
• TOTP support — computes one-time passwords automatically from a stored secret; falls back to a manual OTP dialog if no secret is configured
• Secure credential storage — password and TOTP seed stored exclusively in Android EncryptedSharedPreferences backed by the Android Keystore; SSH key pair generated and held in the Keystore

nnU-Net plugin

A separate plugin APK that connects to SlurmDroid and monitors nnU-Net training on the cluster:

• Dataset list — all datasets discovered under nnUNet_results, nnUNet_raw, and nnUNet_preprocessed, shown with human-readable names parsed from the DatasetXXX_Name convention
• Pipeline status — per-dataset pipeline card showing raw data, planning, preprocessing (with progress bar), training, and postprocessing stages
• Training progress — per-configuration fold list with progress bars, elapsed time, and ETA; overall summary card when multiple folds are present
• Running fold indicator — folds whose training log was updated in the last 15 minutes are marked with a ▶ badge
• Fold detail view — tap any fold for a full detail screen: progress summary, Canvas loss curve (train loss + val loss over all epochs), and a scrollable per-epoch metrics table (train_loss / val_loss / mean Pseudo dice)

Screenshots

Requirements

• Android 8.0+ (API 26)
• SSH access to a Slurm cluster with keyboard-interactive authentication (OTP + password)

Setup

SlurmDroid

1. Install the app and open Settings
2. Enter your cluster hostname, port, and username
3. Enter your password
4. Either scan your TOTP QR code or paste the Base32 secret manually
5. Optionally generate an SSH key pair and add the public key to ~/.ssh/authorized_keys on the cluster for faster reconnects
6. Set a log directory (default: ~/slurm_logs) if your scripts write output files there
7. Tap Test Connection to verify

Credentials are saved automatically as you type.

nnU-Net plugin

1. Install the nnunet-plugin APK alongside SlurmDroid
2. In SlurmDroid → Settings, enable the nnU-Net plugin and set your nnUNet_base_dir (or configure nnUNet_results, nnUNet_raw, and nnUNet_preprocessed individually if you use non-standard paths)
3. Open the nnU-Net app — it connects to SlurmDroid automatically and starts monitoring on the next poll

The plugin respects the standard nnUNet_results, nnUNet_raw, and nnUNet_preprocessed environment variables if the base directory is left blank.

Architecture

app/src/main/java/org/slurmdroid/
├── core/
│   ├── ssh/          # SshManager, SshAuthHandler, CommandExecutor, credential store
│   ├── feature/      # ServerFeature interface + FeatureRegistry
│   ├── notifications/ # JobNotificationManager
│   └── db/           # Room database
├── features/
│   └── slurm/        # Parser, repository, ViewModels, Screens
├── service/          # SshForegroundService — persistent SSH session + polling loop
└── ui/               # MainActivity, AppNavigation, Dashboard, Settings

plugin-api/           # Shared AIDL interface + UI helpers (included in both APKs)

nnunet-plugin/        # Standalone APK — nnU-Net monitoring
└── src/main/java/org/slurmdroid/nnunet/
    ├── data/         # NnUNetLogParser
    ├── domain/       # NnUNetWorkflow, FoldProgress, EpochMetrics, …
    └── ui/           # DatasetListScreen, DatasetDetailScreen, ProgressScreen, FoldDetailScreen

Plugin system: plugins are separate APKs that communicate with SlurmDroid over AIDL. SlurmDroid exposes an ICommandBridge interface so plugins can run SSH commands via the existing connection; plugins expose an ISlurmDroidPlugin interface so SlurmDroid can forward poll ticks and settings. Plugins are auto-discovered by package name, bound on install/update, and can be enabled or disabled per-plugin in Settings.

SSH access is centralized in a single CommandExecutor; no feature or plugin interacts with JSch directly.

Job capture: scontrol show job output is stored for every job seen in squeue and for recently-completed jobs from sacct, so the SubmitLine is available for re-submission even for jobs that were never submitted through the app.

Tech stack

Layer	Library
UI	Jetpack Compose + Material 3
Navigation	Navigation Compose
DI	Hilt
SSH	JSch
TOTP	java-otp
Local DB	Room
Secure storage	EncryptedSharedPreferences + Android Keystore
Background work	WorkManager + Foreground Service
Cross-process	AIDL

Building

# Main app
./gradlew :app:assembleDebug

# nnU-Net plugin APK
./gradlew :nnunet-plugin:assembleDebug

Requires Android SDK with API 35 build tools. No API keys or secrets needed for a local build.

License

This project is licensed under the GNU General Public License v3.0 — see the LICENSE file for details.