Linux root user's manual
Change to root user
su - run a shell with substitute user and group IDs
$ su - root
Password : ********
#
Shutdownn
# halt
or
# shutdown -h now
Reboot
# reboot
or
# shutdown -r now
Make Group
Edit /etc/group
staff:x:500:
trainee:x:501:
Make General user. (This user can use telnet)
useradd [UserName] -g [GroupId]
# useradd hoge -g staff
# passwd hoge
Mount CD-ROM Drive
Mount
# mount /mnt/cdrom
Unmount
# umount /mnt/cdrom
# eject
Mount file system
Mount ISO file by command
# mount suse-10.0-dvd.iso /mnt/suse -o loop
Mount SMB (windows file sharing) by command
# mount -t smbfs -o username=administrator,password=123 //srv1/share /mnt/srv1/
Mount file systems automatically, edit /etc/fstab
/somewhere/suse-10.0-dvd.iso /mnt/suse iso9660 ro,loop 0 0
//srv1/share /mnt/srv1/ smbfs username=administrator,password=123 0 0
cron - daemon to execute scheduled commands (Vixie Cron)
# crontab -u root -e
Edit like this
0 4 * * * /root/bin/test
| Colums |
|
|---|
| 1 | minute
|
|---|
| 2 | hour
|
|---|
| 3 | month
|
|---|
| 4 | year
|
|---|
| 5 | day of week(0:Sunday, 1:Monday, ...7:Saturday)
|
|---|
rpm - Red Hat Package Manager
Install
# rpm -ivh package.rpm
Install from source
# rpm --rebuild package.src.rpm
Update
# rpm -Uvh package.rpm
Uninstall
# rpm -e package
Installed packages list
# rpm -qa | less
See the pachage's information
# rpm -qi apache
See the pachage's file list
# rpm -ql apache
Query the package which contains the file
# rpm -qf /etc/passwd
setup-2.5.12-1
See dependancies to install the pachage
# rpm -q --requires apache
# rpm -qR apache
RPM packages's download site
http://rufus.w3.org/linux/RPM/
df - summarize free disk space
# df
Filesystem 1024-blocks Used Available Capacity Mounted on
/dev/hda7 256592 201147 42193 83% /
/dev/hda8 256592 74744 168596 31% /home
/dev/hda5 1732961 476993 1166408 29% /usr
/dev/hda6 1732961 430138 1213263 26% /var
bashrc - Login script
/etc/bashrc
# /etc/bashrc
# System wide functions and aliases
# Environment stuff goes in /etc/profile
alias llmo="ls -lt | less"
................
tar - tape file archiver
Backup to a tape device
# tar cvf /dev/rst0 /usr
List the contents of an archive
# tar tvf /tmp/etcbackup.tar
Create a new archive
# tar cvf /tmp/etcbackup.tar /etc
Extract files from an archive
# tar xvf /tmp/etc/backup.tar
Create a new archive with compression
# tar zcvf log.tar.gz log
Extract files from a compressed archive
# tar zxvf log.tar.gz
compress - compress and expand data
Compress
# ls -lt test.tgz
-rw-r--r-- 1 root root 604160 Aug 26 05:31 test.tgz
# compress test.tgz
# ls -lt test.tgz*
-rw-r--r-- 1 root root 56373 Aug 26 05:31 test.tgz.Z
#
Expand
# ls -lt test.tgz*
-rw-r--r-- 1 root root 56373 Aug 26 05:31 test.tgz.Z
# uncompress test.tgz.Z
# ls -lt test.tgz
-rw-r--r-- 1 root root 604160 Aug 26 05:31 test.tgz
du - summarize disk usage
/root/.bashrc
...
alias dsk='du -ks * .* | sort -n'
...
# cd /home
# dsk
du: ../proc/4620/fd/4: No such file or directory
1 samba
12 lost+found
386 hoge
1068 ftp
1541 httpd
3009 .
342510 ..
# cd /
# dsk
du: proc/4622/fd/4: No such file or directory
du: ./proc/4622/fd/4: No such file or directory
du: ../proc/4622/fd/4: No such file or directory
0 proc
3 mnt
12 lost+found
39 dev
635 boot
654 root
1156 tmp
2245 sbin
2274 etc
3009 home
3871 bin
8919 var
12333 lib
307359 usr
342510 .
342510 ..
e2fsck - check a Linux second extended file system
e2fsck is used to check a Linux second extended file system.
If you get these messages while booting your Linux box, use e2fsck command
...
/dev/sdb1: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
(i.e., without -a or -p options)
----------------------------------
*** An error occurred during the file system check.
*** Dropption you to a shell; the system will reboot
*** when you leave the shell.
Givi root password for maintenance
(or type Control-D for normal startup): Password
# /sbin/e2fsck /dev/sdb1
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