Troubleshoot

1

Recovering Root Password

Root Password can be recovered in a specialized troubleshooting mode (i.e. init 1) init 1 level provides a shell (i.e. sh) without logging in.

2

Recovering Root Password

Procedure Procedure Restart Restartthe thesystem system In the splash In the splashscreen screenSelect Select RedHat RedHatEnterprise Enterprise Linux Linux Press e Press Select SelectKernel Kernel/vmlinuz-2.6.9-5.EL /vmlinuz-2.6.9-5.ELro roroot=LABEL=/rhgb root=LABEL=/rhgbquiet quiet Press e to edit Press to edit Edit EditKernel Kernel/vmlinuz-2.6.9-5.EL /vmlinuz-2.6.9-5.ELro roroot=LABEL=/rhgb root=LABEL=/rhgbquiet quiet11 Press Press Enter Enter Press Press b to toboot bootwith withthe the selected selectedrun run level level directly directlyyou youwill willget getshell shellprompt promptto toassign assignthe theroot rootpassword password sh-3.00#passwd sh-3.00#passwdroot root

3

Assigning Grub Password

Assigning AssigningGrub GrubPassword Password [root@comp1~]# grub-md5-crypt >> [root@comp1~]# grub-md5-crypt >>/boot/grub/grub.conf /boot/grub/grub.conf [root@comp1~]# [root@comp1~]#vi vi/boot/grub/grub.conf /boot/grub/grub.conf

Add Add line linein in/boot/grub/grub.conf /boot/grub/grub.conf hidden hiddenmenu menu password password --md5 --md5 <password> <password> title Red Hat -----title Red Hat ------

4

Recovering Grub Password

Recovering RecoveringGrub GrubPassword Password Boot the System in Rescue Mode Boot the System in Rescue Mode # # # #

chroot chroot /mnt/sysimage /mnt/sysimage vi /boot/grub/grub.conf vi /boot/grub/grub.conf

Remove Removeline linefrom from/boot/grub/grub.conf /boot/grub/grub.conf hidden menu hidden menu password password ---md5 md5 <password> <password> title Red Hat -----title Red Hat ------

5

Other Configurations

To Toconfigure configureprinter printer [root@comp1~]# system-config-printer [root@comp1~]# system-config-printer

To Toconfigure configuremodem modem [root@comp1~]# system-config-network-druid [root@comp1~]# system-config-network-druid

6

Other Configurations

To Toview viewthe theprocess process [root@comp1~]# ps -aux [root@comp1~]# ps -aux

To Tokill killaaspecific specific process process [root@comp1~]# kill -9 <process id> [root@comp1~]# kill -9 <process id>

To Toview viewCPU CPU usage usageby byall allprocess process [root@comp1~]# [root@comp1~]#top top

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