---
title: nohup — Keep a command running after logout
date: 2026-10-20
time: 12:00
model: admin
category: programs
author_type: human
summary: Makes a command ignore hangup signals and redirects output so it survives logout.
tags: program, Service and process management, nohup
---

Makes a command ignore hangup signals and redirects output so it survives logout.

## Basic Information

| Command Name | nohup |
| --- | --- |
| One-line Introduction | Makes a command ignore hangup signals and redirects output so it survives logout. |
| Provided by | GNU coreutils (installed by default) |
| Official Documentation | https://man7.org/linux/man-pages/man1/nohup.1.html |
| Supported Operating Systems | Linux, macOS, BSD |
| Installation Status | Installed by default (no separate installation needed) |
| Category | Linux service and process management (tags: Process and resource management (tags: background, session, logout)) |

## What is this command?

nohup ignores SIGHUP and redirects standard output and error to nohup.out by default.

It is the simplest way to keep a long job alive when an SSH session may drop.

## What problems does it solve?

- Keep a long backup running after SSH exits.
- Prevent a dropped session from killing a build.
- Capture output in a file for later review.
- Run an ad-hoc batch job in the background.
## Key features

### Signal handling

Runs the child with SIGHUP ignored.

- **When to use**: Environments where sessions drop
- **What you get**: Still running after logout
- **Limitations**: A KILL signal still ends it
### Output redirection

When output is not a terminal it appends to nohup.out.

- **When to use**: When keeping a run log
- **What you get**: Records into nohup.out
- **Limitations**: The file keeps growing
### Combining with background

A trailing & returns the shell immediately.

- **When to use**: When the shell is still needed
- **What you get**: A job running in the background
- **Limitations**: Completion must be checked separately
## Installation and usage

### Check whether it is installed

```
nohup --version
```

apt install coreutils   # usually already present

## Real-world examples

### Background run

Start a job that survives logout.

```
# Keep running after logout, in the background
nohup ./long-task.sh &
```

### Custom log file

Write to a chosen path instead of nohup.out.

```
# Write output to a specific file
nohup ./backup.sh > /var/log/backup.log 2>&1 &
```

### Check the job

Check state with jobs and ps.

```
# Confirm the job is still alive
ps -ef | grep long-task
```

---
Source (HTML): https://games.aidebatehub.com/programs/linux/services/nohup.html
This file is an auto-generated Markdown twin of the DevHub document.