---
title: "System Default Users"
slug: "system-default-users"
tags: ["5.4"]
updated: 2026-10-28T01:53:23Z
published: 2026-10-28T01:53:23Z
canonical: "docs.vastdata.com/system-default-users"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vastdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# System Default Users

The following table lists system users with `/sbin/nologin`.

- These users are not intended for logging in.
- None of these users has a password set by default.
- Critical system users cannot be deleted.

> [!WARNING]
> Warning
> 
> Deleting critical system users may result in service disruption.

| User | Purpose | Can be deleted? |
| --- | --- | --- |
| `dbus` | Runs D-Bus, a message bus system that provides inter-process communication for system services like hardware abstraction. | No |
| `polkitd` | Runs `polkit` (former PolicyKit), a tool for privilege escalation in system services. | No |
| `sshd` | Runs OpenSSH server (`sshd`) securely in a restricted environment. | No |
| `rpc` | Runs the `rpcbind` daemon that manages Remote Procedure Call (RPC) services, used in NFS and other RPC-based systems. | No |
| `pcp` | Runs Performance Co-Pilot (PCP), a system performance monitoring tool. | Yes > [!NOTE] > Note > > PCP is not used and will be removed in a later release of VAST OS. |
| `chrony` | Runs `chrony`, a time synchronization daemon (an alternative to `ntp`). | No |
| `rngd` | Runs the random number generator daemon (`rngd`) which improves entropy for cryptographic operations. | No |
| `nobody` | Generic unprivileged user that is used by various services when they need to drop privileges to minimize security risks. | No |
| `systemd-coredump` | Runs `systemd` core dumper that handles core dumps for debugging application crashes. | Yes > [!NOTE] > Note > > Core dumping is disabled. |