Tips for Linux

1. Change the Host Name
Add HOSTNAME = host name in the/etc/sysconfig/network File
$ Hostname: Host Name.

2. mount
Mount-o codepage = 936, iocharset = cp936, gb2312, utf8

3. delete an object 0 in size
Rm-I 'Find./-size 0' or
Find./-size 0-exec rm {}/; or
Find./-size 0 | xargs rm-f or
For file in *
Do
If [! -S $ file]
Then
Rm $ file
Echo "rm $ file success! "
Fi
Done

4. Set scroll wheel and mouse
Change PS/2 in/etc/X11/Xf86Config to ImPS/2.

5. tar volume compression and merge (MB)
Tar cvzfp-mytarfile | split-B 500 m
Cat x *> mytarfile.tar.gz

6. merge two files
1) retrieve the collection of two files (only one copy is retained for repeated rows) cat file1 file2 | sort | uniq
2) extract the intersection of the two files (leaving only the duplicate rows of the two files at the same time) cat file1 file2 | sort | uniq-d
3) Delete the intersection and leave other lines cat file1 file2 | sort | uniq-u

7. Set the com1 port so that the Super Terminal can log on through the com1 port.
Confirm/sbin/agetty, edit/etc/inittab, and add
7: 2345: respawn:/sbin/agetty/dev/ttyS0 9600
9600bps is because the rate is generally set by default for a vro. It can also be set to 57600, 115200, or.
Modify/etc/securetty and add a line: ttyS0 to ensure that the root user can log on.

8. startx starts gnome or KDE
Edit file ~ /. Xinitrc added
Exec gnome-session or exec startkde, and then use startx.

9. Change the redhat System Language/Character Set
Modify the/etc/sysconfig/i18n File
LANG = "en_US"
LANG = "zh_CN.GB18030"
Or modify ~ /. I18n
LANG = "zh_CN.GB18030"
Or
~ /. Bashrc
Export LANG = zh_CN.GB2312

10. Set the screen to 90 Columns
Stty cols 90

11. md5sum
Md5sum file> md5 to generate an md5 code
Md5sum-c md5 check file

12. Find the file with the S permission.
Find-type F/(-Perm 04000-o-Perm 02000/)-exec LS-l {}/;

13. pop up the CD
Eject/mnt/CDROM
Reclaim
Eject-T/mnt/CDROM

14. Set the time
Date-s "2003-05-18 CST" CST indicates the time zone
Time Setting: Date-S
After modification, execute clock-W to write to CMOS.
Hwclock -- systohc

15. Search for files in multi-level Directories
Find./Dir-name file-print
Du-A | grep-I file
Locate filename

16. After installation, use ISO to add and delete the RPM package.
RedHat-config-packages -- isodir =

17. editing the inittab file takes effect directly.
Init Q

18. Install grub into MBR
Grub> root (ha0, 0)
Grub> setup (hd0)
Or install grub-install/dev/hda.

19. Disable PC speakers in text
In/etc/inputrc
Set bell-style none
Or
Echo "set bell-style none" >> ~ /. Bashrc

20. ls only lists Directories
Ls-lF | grep ^ d
Ls-lF | grep/$
Ls-F | grep ^ d

21. ctrl + s and ctrl + q
Ctrl + s pause sending data to the terminal
Ctrl + q restore

22. delete the file containing the specified string in the directory.
Find dir-type f-exec grep "string" {}/;-print-exec rm {}/;

23. gs merge two ps or PDF files
Gs-q-dNOPAUSE-dBATCH-sDEVICE = pswrite-sOutputFile = bar. ps-f part1.ps part2.ps
Gs-q-dNOPAUSE-dBATCH-sDEVICE = paiwrite -soutputfile?bar=- f part1.pdf part2.pdf

24. vim does not ring the bell
Echo "set vb t_vb" >> ~ /. Vimrc

25. Start or close the service
Ntsysv -- level n
Chkconfig -- list all services
Chkconfig name on/off enable or disable the service name

26. Change IP Address
Ifconfig eth0 ip netmask ip
Then modify IPADDR in the/etc/sysconfig/network-scripts/ifcfg-eth0 File

27. Change the default gateway
Route add default GW gateway IP Address
Edit gateway in the/etc/sysconfig/network-scripts/ifcfg-eth0 File
You can also change the subnet mask and network card hardware address.

Hwaddr = 00: E0: 81: 21: 01: 26
Ipaddr = 159.226.119.111
Netmask = 159.226.119.192
Gateway = 159.226.119.126

28. Check what programs are running on port 22.
Lsof-I: 22

29. Change DNS
Edit nameserver dnsip in the/etc/resolv. conf file

30. Modify the MAC address
/Sbin/ifconfig eth0 down
/Sbin/ifconfig eth0 HW ether 00: AA: BB: CC: DD: EE
/Sbin/ifconfig eht0 up

31. Change the default system configuration.
Sysctl-W net. ipv4.ip _ default_ttl = N
Or edit the file.
/Etc/sysctl. conf
Net. ipv4.ip _ forward = 0
View the changes using the sysctl command
Sysctl-

32. Ssh configuration file
/Etc/ssh/sshd_config
Permitrootlogin no/yse
Allow root users to log on via SSH
Port 2222 changes the sshd Port

33. allow root Telnet
Edit file/etc/securetty added
PTS/0
PTS/1
Change telnet port
In/etc/services, the corresponding port of teknet is changed from 21 to the desired port.

34. Bind two IP addresses to one network card
CD/etc/sysconfig/network-Scripts
CP ifcfg-eth0 ifcfg-eth0: 1
Modify ifcfg-eth0: 1 change IP and device name

35. bind an IP address to two NICs
IP: 192.168.0.88
Gateway: 192.168.0.1

/Sbin/modprobe bonding miimon = 100 mode = 1
/Sbin/ifdown eth0
/Sbin/ifdown eth1
/Sbin/ifconfig bond0 192.168.0.88
/Sbin/ifenslave bond0 eth0 eth1
/Sbin/route add default GW 192.168.0.1

36. Immediately enable Linux to support NAT
Echo 1>/proc/sys/NET/IPv4/ip_forwar
Iptables-T nat-I postroutine-J Masquerade

37. Simple route settings
View route settings
Netstat-Rn
Route-n
Manually add a route
Route add-net 192.168.0.0 netmask 255.255.255.0 GW 172.16.0.1
Manually delete a route
Route del-net 192.168.0.0 netmask 255.255.255.0 GW 172.16.0.1
Modify the/etc/sysconfig/static-routes file to add a route
Any net 192.168.0.0 netmask 255.255.255.0 GW 172.16.0.1

38. Add the default lib LIBRARY PATH
Export ld_libary_path = $ ld_libary_path:/usr/local/lib
Write ~ /. Bashrc
Or add it to/etc/lD. So. conf.
/Usr/local/lib: Execute ldconfig.