11. View and test network, configure network address, kernel and module management

I. Linux backup strategy

1.tar Full Backup

-N YYYY-MM-DD Backup: Post-update documents

File See CTime

Catalogue See Atime

- p retain the original attribute permission

- P retains the original absolute path unchanged

--exclude Exclude documents that do not need to be backed up

2.touch: Modify file time and create new file

Atime: The contents of the file are taken, such as Cat

Mtime: File content data is changed

CTime: Changes in the state of a file, such as permissions and attributes

Ls-lu View Atime

L View Mtime

-lu View CTime

3.stat: View response time information for the corresponding file

4.dump-level [options] ...-f backup location source data

-0 Full Backup 1 backup after 0 changes, 2 backup after 1 changes

-j Enable bzip2

-s check how much disk space is required for this backup

-U updates the time of this backup to/etc/dumpdates when backing up a single file system

-W checks if the flagged dump partition has been backed up

5.restore [Options] ...-f backup location

-T View the list of backup documents

-R recovering data from backup location

-X refers to data from a backup device (non-compressed)

-C Compare backup files to current file differences

-I interactive recovery operation mode

6. Make a full backup for/boot

dump-0-f/root/boot.dump/dev/sda1

7. Recover/boot partition

-f Specifies the location of the backup

Cd/boot//Switch to destination folder

RESTORE-TF/ROOT/BOOT.DMP//Check Backup

RESTORE-RF/ROOT/BOOT.DMP//Recover Data

8. Make ISO image from CD

Copy disc mirroring using CP

-Direct CP device file, not mount directory

Cp/dev/cdrom/bak/linux-tools.iso

Ls/bak

Mount-o loop/bak/linux-tools.iso/mnt//Mount image file to folder

File Rhel-5.9x86_64_dvd.iso//view files type

Or

DD If=/dev/cdrom Of=/isos/rhel.iso

Or

Cat/dev/cdrom >/isos/rhel.iso

Two. System troubleshooting

1. Device Copy/Clone

DD tool, direct read and write magnetic sector

-D if= input device of= output device bs= block size count= block number

Copy disk SDA to SDB block size = 512 bytes =mbr

dd IF=/DEV/SDA of=/dev/sdb bs=512 conut=1

2. Recovering MBR sector failures

DD IF=/DEV/SDA of=/mnt/sdb1/sda.mbr bs=512 conut=1//Backup

DD If=/dev/zero OF=/DEV/SDA bs=512 conut=1//destruction

Mkdir/tdir; Create a new Folder

Mount/dev/sdb1/tdir//Mount backup disk

DD if=/tdir/sda.mbr OF=/DEV/SDA bs=512 count=1

3. (1) Fix grub boot failure

1. After the grub> prompt, manually perform the boot

Grub>root (hd0,0)

Grub>kernel/vm. RO root=/dev/sda2//the partition where the root file is located

Grub>initrd/initrd ...

Grub>boot

2. After entering the system, rebuild the grub.conf configuration file

(2) When the Grub boot program is destroyed, it needs to go into repair mode and rebuild the GRUB program.

Chroot/mnt/sysimage//Switch to the system you want to repair

cd/boot/grub/

GRUB-INSTALL/DEV/SDA//Rebuilding Grub Boot

After entering the system, rebuild the grub.conf configuration file

4./ect/inittab file is missing

Fault is now like

Start Prompt "... Init:no inittab file Found "

Solution: Reload the initscripts package in first aid mode

Chroot/mnt/sysimage

MOUNT/DEV/HDC/MNT//Mount

RPM-IVH/MNT/SERVER/INITSCRIPTS-.RPM--force//Forced installation

5. Forgotten Root User password

Boot in single user mode, then reset password

Grub>kernel ... 1//Enter the Grub interface press the E cursor to navigate to the kernel and then press the e space to write 1

Enter and press B to start the Reset password passwd 123

This article is from the "Wsyht blog" blog, make sure to keep this source http://wsyht2015.blog.51cto.com/9014030/1790254

11. View and test network, configure network address, kernel and module management