El inicio de un sistema en estado de usuario único se utiliza para realizar tareas de mantenimiento del sistema, por ejemplo, para hacer una copia de seguridad de un sistema de archivos o resolver problemas del sistema.
# init 0
ok boot -s
SINGLE USER MODE Root password for system maintenance (control-d to bypass): xxxxxx
# reboot -p
Dado que la función Fast Reboot está activada de manera predeterminada, debe especificar la opción –p al reiniciar el sistema, lo que permite mostrar el menú de GRUB en el inicio. Para desactivar la función Fast Reboot para que no sea necesario especificar la opción –p, consulte Modificación del comportamiento predeterminado de Fast Reboot.
Consulte Agregación de argumentos del núcleo mediante la edición del menú de GRUB en el inicio para obtener más información sobre cómo editar el menú de GRUB en el inicio.
# who -r
En el siguiente ejemplo, se muestran los mensajes que aparecen al iniciar un sistema basado en SPARC en el nivel de ejecución S una vez que ha comenzado el proceso de inicio.
# init 0 # svc.startd: The system is coming down. Please wait. svc.startd: 122 system services are now being stopped. Mar 5 10:30:33 system1 syslogd: going down on signal 15 svc.startd: Killing user processes. umount: /ws busy umount: /home busy Mar 5 17:30:50 The system is down. Shutdown took 70 seconds. syncing file systems... done Program terminated {1c} ok boot -s SC Alert: Host System has Reset NOV 17 21:46:59 ERROR: System memory downgraded to 2-channel mode from 4-channel mode NOV 17 21:47:00 ERROR: Available system memory is less than physically installed memory NOV 17 21:47:00 ERROR: System DRAM Available: 008192 MB Physical: 016384 MB Sun Fire T200, No Keyboard . . . Ethernet address 0:14:4f:1d:e8:da, Host ID: 841de8da. ERROR: The following devices are disabled: MB/CMP0/CH2/R0/D0 Boot device: /pci@7c0/pci@0/pci@1/pci@0,2/LSILogic,sas@2/disk@0,0:a File and args: -s SunOS Release 5.11 Version 11.2 64-bit Copyright (c) 1983, 2014, Oracle and/or its affiliates. All rights reserved. NOTICE: Hypervisor does not support CPU power management Booting to milestone "milestone/single-user:default". Hostname: system1 Requesting System Maintenance Mode SINGLE USER MODE Enter root password (control-d to bypass): xxxxxx single-user privilege assigned to root on /dev/console. Entering System Maintenance Mode Mar 5 10:36:14 su: 'su root' succeeded for root on /dev/console Oracle Corporation SunOS 5.11 11.2 July 2014 root@system1:~# who -r run-level S Mar 5 10:35 S 0 0 root@tsystem1:~#Ejemplo 4-15 x86: Inicio de un sistema en un estado de usuario único (nivel de ejecución S)
En el siguiente ejemplo, se muestran los mensajes que aparecen al iniciar un sistema basado en x86 en el nivel de ejecución S una vez que ha comenzado el proceso de inicio.
root@system-04:~# init 0 root@system-04:~# svc.startd: The system is coming down. Please wait. svc.startd: 129 system services are now being stopped. Apr 23 13:51:28 system-04 syslogd: going down on signal 15 svc.startd: Killing user processes. umount: /home busy Apr 23 13:51:36 The system is down. Shutdown took 26 seconds. syncing file systems... done Press any key to reboot. . . .LSI Corporation MPT SAS BIOS MPTBIOS-6.26.00.00 (2008.10.14) Copyright 2000-2008 LSI Corporation. Initializing..|Press F2 to runS POPUP (CTRL+P on Remote Keyboard) Press F12 to boot from the network (CTRL+N on Remote Keyboard) System Memory : 8.0 GB , Inc. Auto-Detecting Pri Master..ATAPI CDROM 0078 Ultra DMA Mode-2 . . . GNU GRUB version 1.99,5.11.0.175.1.0.0.14.0 **************************************************************************** *Oracle Solaris 11.2 * * * * * * * * * * * * * * * * * * * * * **************************************************************************** Use the * and * keys to select which entry is highlighted. Press enter to boot the selected OS, 'e' to edit the commands before booting or 'c' for a command-line. GNU GRUB version 1.99,5.11.0.175.1.0.0.14.0 **************************************************************************** * setparams 'Oracle Solaris 11.2' * * * * insmod part_msdos * * insmod part_sunpc * * insmod part_gpt * * insmod zfs * * search --no-floppy --fs-uuid --set=root cd03199c4187a7d7 * * zfs-bootfs /ROOT/s11u2/@/ zfs_bootfs * * set kern=/platform/i86pc/kernel/amd64/unix * * echo -n "Loading ${root}/ROOT/s11u2 /@$kern: " * * $multiboot /ROOT/s11u2/@/$kern $kern -B $zfs_bootfs -s * set gfxpayload="1024x768x32;1024x768x16;800x600x16;640x480x16;640x480x1\ * * 5;640x480x32" ** **************************************************************************** Minimum Emacs-like screen editing is supported. TAB lists completions. Press Ctrl-x or F10 to boot, Ctrl-c or F2 for a command-line or ESC to discard edits and return to the GRUB menu. Booting a command list Loading hd0,msdos1,sunpc1/ROOT/s11u2/@/platform/i86pc/kernel/amd64/unix: 0 %...done. Loading hd0,msdos1,sunpc1/ROOT/s11u2/@/platform/i86pc/amd64/boot_archive: 0%... . . . SunOS Release 5.11 Version 11.2 64-bit Copyright (c) 1983, 2014, Oracle and/or its affiliates. All rights reserved. NOTICE: kmem_io_2G arena created Booting to milestone "milestone/single-user:default". Hostname: system-04 Requesting System Maintenance Mode SINGLE USER MODE Enter user name for system maintenance (control-d to bypass): root Enter root password (control-d to bypass): xxxxxxx single-user privilege assigned to root on /dev/console. Entering System Maintenance Mode May 8 11:13:44 su: 'su root' succeeded for root on /dev/console Oracle Corporation SunOS 5.11 11.2 July 2014 You have new mail. root@system-04:~# who -r . run-level S Apr 23 14:49 S 0 0