Something to share

yongpeng

Thanks to anyone share their knowledge before, i put some some basic notes for linux administrator, anyone help to translate to chinese will be greatly appreciate.


to stop a process id 1000 :

# kill -STOP 1000

resume the process

# kill -CONT 1000


clone harddisk partition :

# dd if=/dev/hda1 of=/dev/hdb1

very slow compare to norton ghost, use it unless not choice


backup /bin and restore to /var ( best way for people want to move their small partition to other big partition)

# tar c var | (cd /newvar ;tar xp)


do "# make mrproper"  before you compile kernel source ( RedHat, Mandrake .....)


check server open tcp port :

# netstat -tan | more

check users that access to port 1000

# fuser -v -n tcp 1000

list the files open by port 1000

# lsof -i : 1000



Linux EXT2/3 recovery (use if you can't recover filesystem in single user mode with fsck /dev/hda1)

# fsck -b 32768 /dev/hda1

1k Blocksize =>; 8193
2k Blocksize =>; 16384
4k Blocksize =>; 32768


lock user account :

# passwd user1 -l

unlock account :

# passwd user1 -u


make COM1 device file :

# mknod -m 666 /dev/ttyS0 c 4 64

or ( # MAKEDEV ttyS0)


Linux Magic System Key (Sysrq), required kernel compile with the option. ( use when system hang)

ALT + SysRq + i ==>; Kill all process
ALT + SysRq + s ==>; sync buffers to disk
ALT + SysRq + u ==>; umount linux to read-only filesystems   
ALT + SysRq + b ==>; reboot

press ALT, SysRq(print screen??) and i key together.