{ "content": [ { "type": "text", "text": "# sulogin (man)\n\n## NAME\n\nsulogin - single-user login\n\n## SYNOPSIS\n\nsulogin [options] [tty]\n\n## DESCRIPTION\n\nsulogin is invoked by init when the system goes into single-user mode.\n\n## TLDR\n\n> Log in as root during single-user mode.\n\n- Start `sulogin` on the default console:\n `sudo sulogin`\n- Start `sulogin` on a specific TTY device:\n `sudo sulogin {{/dev/ttyX}}`\n- Set a maximum timeout(in seconds) for entering the root password before continuing normal boot:\n `sudo sulogin {{-t|--timeout}} {{timeout}}`\n- Start root's shell as a login shell:\n `sudo sulogin {{-p|--login-shell}}`\n- Force a root shell without asking for a password when default methods of obtaining the password fail:\n `sudo sulogin {{-e|--force}}`\n\n*Source: tldr-pages*\n\n## Sections\n\n- **NAME**\n- **SYNOPSIS**\n- **DESCRIPTION**\n- **OPTIONS** (5 subsections)\n- **ENVIRONMENT**\n- **AUTHORS**\n- **REPORTING BUGS**\n- **AVAILABILITY**\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n" } ], "structuredContent": { "command": "sulogin", "section": "", "mode": "man", "summary": "sulogin - single-user login", "synopsis": "sulogin [options] [tty]", "tldr_summary": "Log in as root during single-user mode.", "tldr_examples": [ { "description": "Start `sulogin` on the default console", "command": "sudo sulogin" }, { "description": "Start `sulogin` on a specific TTY device", "command": "sudo sulogin {{/dev/ttyX}}" }, { "description": "Set a maximum timeout(in seconds) for entering the root password before continuing normal boot", "command": "sudo sulogin {{-t|--timeout}} {{timeout}}" }, { "description": "Start root's shell as a login shell", "command": "sudo sulogin {{-p|--login-shell}}" }, { "description": "Force a root shell without asking for a password when default methods of obtaining the password fail", "command": "sudo sulogin {{-e|--force}}" } ], "tldr_source": "official", "flags": [ { "flag": "-e", "long": "--force", "arg": null, "description": "If the default method of obtaining the root password from the system via getpwnam(3) fails, then examine /etc/passwd and /etc/shadow to get the password. If these files are damaged or nonexistent, or when root account is locked by '!' or '*' at the begin of the password then sulogin will start a root shell without asking for a password. Only use the -e option if you are sure the console is physically protected against unauthorized access." }, { "flag": "-p", "long": "--login-shell", "arg": null, "description": "Specifying this option causes sulogin to start the shell process as a login shell." }, { "flag": "-t", "long": "--timeout", "arg": null, "description": "Specify the maximum amount of time to wait for user input. By default, sulogin will wait forever." }, { "flag": "-h", "long": "--help", "arg": null, "description": "Display help text and exit." }, { "flag": "-V", "long": "--version", "arg": null, "description": "Display version information and exit." } ], "examples": [], "see_also": [], "section_outline": [ { "name": "NAME", "lines": 2, "subsections": [] }, { "name": "SYNOPSIS", "lines": 2, "subsections": [] }, { "name": "DESCRIPTION", "lines": 14, "subsections": [] }, { "name": "OPTIONS", "lines": 1, "subsections": [ { "name": "-e --force", "lines": 8, "flag": "-e", "long": "--force" }, { "name": "-p --login-shell", "lines": 2, "flag": "-p", "long": "--login-shell" }, { "name": "-t --timeout", "lines": 3, "flag": "-t", "long": "--timeout" }, { "name": "-h --help", "lines": 2, "flag": "-h", "long": "--help" }, { "name": "-V --version", "lines": 2, "flag": "-V", "long": "--version" } ] }, { "name": "ENVIRONMENT", "lines": 4, "subsections": [] }, { "name": "AUTHORS", "lines": 3, "subsections": [] }, { "name": "REPORTING BUGS", "lines": 2, "subsections": [] }, { "name": "AVAILABILITY", "lines": 6, "subsections": [] } ], "sections": { "NAME": { "content": "sulogin - single-user login\n", "subsections": [] }, "SYNOPSIS": { "content": "sulogin [options] [tty]\n", "subsections": [] }, "DESCRIPTION": { "content": "sulogin is invoked by init when the system goes into single-user mode.\n\nThe user is prompted:\n\nGive root password for system maintenance (or type Control-D for normal startup):\n\nIf the root account is locked and --force is specified, no password is required.\n\nsulogin will be connected to the current terminal, or to the optional tty device that can be\nspecified on the command line (typically /dev/console).\n\nWhen the user exits from the single-user shell, or presses control-D at the prompt, the\nsystem will continue to boot.\n", "subsections": [] }, "OPTIONS": { "content": "", "subsections": [ { "name": "-e --force", "content": "If the default method of obtaining the root password from the system via getpwnam(3)\nfails, then examine /etc/passwd and /etc/shadow to get the password. If these files are\ndamaged or nonexistent, or when root account is locked by '!' or '*' at the begin of the\npassword then sulogin will start a root shell without asking for a password.\n\nOnly use the -e option if you are sure the console is physically protected against\nunauthorized access.\n", "flag": "-e", "long": "--force" }, { "name": "-p --login-shell", "content": "Specifying this option causes sulogin to start the shell process as a login shell.\n", "flag": "-p", "long": "--login-shell" }, { "name": "-t --timeout", "content": "Specify the maximum amount of time to wait for user input. By default, sulogin will wait\nforever.\n", "flag": "-t", "long": "--timeout" }, { "name": "-h --help", "content": "Display help text and exit.\n", "flag": "-h", "long": "--help" }, { "name": "-V --version", "content": "Display version information and exit.\n", "flag": "-V", "long": "--version" } ] }, "ENVIRONMENT": { "content": "sulogin looks for the environment variable SUSHELL or sushell to determine what shell to\nstart. If the environment variable is not set, it will try to execute root’s shell from\n/etc/passwd. If that fails, it will fall back to /bin/sh.\n", "subsections": [] }, "AUTHORS": { "content": "sulogin was written by Miquel van Smoorenburg for sysvinit and later ported to util-linux by\nDave Reisner and Karel Zak.\n", "subsections": [] }, "REPORTING BUGS": { "content": "For bug reports, use the issue tracker at https://github.com/karelzak/util-linux/issues.\n", "subsections": [] }, "AVAILABILITY": { "content": "The sulogin command is part of the util-linux package which can be downloaded from Linux\nKernel Archive .\n\n\n\nutil-linux 2.37.2 2021-06-02 SULOGIN(8)", "subsections": [] } } } }