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Table of Contents [show]     1 Linux boot process     2 Setting Up Printers on Fedora Core 4     3 How to install chinese font on Fedora Core?     4 nohup     5 Linux partitions     6 How Do I mount a windows share on linux     7 How to setup TwinView (Dual Head, Dual Monitor) on Fedora Core 4       7.1 Setup       7.2 Step 1: wire up hardware       7.3 Step 2: download driver from nvidia website       7.4 Step 3: run the setup program       7.5 Step 4: Update your /etc/X11/xorg.conf       7.6 Step 5: Check     8 How to mount ntfs file system (a windows hard drive)     9 How to recompile the kernel     10 How to setup static ipaddress?     11 how to setup my screensaver in GNOME     12 How to set up dns server     13 How to change time zone?     14 How to setup network time sync server?     15 How do I add a second disk?     16 How do I use X on my windows?     17 What's the difference between nfs and samba?     18 I am using vi, how do I disable auto wrapping?     19 How to enable auto login on linux?     20 How do I setup global variables?     21 How do automatically run programs after a GDM autologin?     22 cannot restore segment prot after reloc     23 How to setup timezone in linux?     24 boot scripts     25 Error while loading shared libraries: libfuse.so.2     26 Ubuntu: Root login not allowed     27 How to set runlevel in Ubuntu?     28 How to setup network on gentoo?     29 How do I mount an LVM on Ubuntu?     30 How do I add a user to a specific group?     31 How do I autologin a user in gdm?     32 What's the initial ubuntu root password?     33 How do I install x on linux     34 How do I kill a process by name     35 How do I install fuse?     36 I am using Redhat Enterprise RHEL, and yum doesn't seem to be working, what do I do?     37 How to change hostname?     38 I think I have the correct host:/path and mount-point, why cannot I mount an nfs share?     39 Where's my lsof? I am using Redhat, and yum shows lsof as installed     40 Failed to mount NFS share, reason given by server: Permission denied     41 How do I create an ext3 file system?     42 I just bought a new disk, how do I create and export a file system as NFS share?     43 I am using redhat and I got this error: Abuse of service deteced for server xxxx     44 How do I create an ext2 file system?     45 How do I create a non login user?     46 How do I create a restricted user?     47 Cannot determine the version of the linux kernel source?     48 Using Ubuntu, how do I install g++?     49 I am trying to install fuse on Redhat advanced server 4, configure/make/make install went on fine, however, I kept getting "module not found error" when I do modprobe     50 I lost my Ubuntu root password, how do I reset it?     51 How do I change my locale in Ubuntu, for example to Japanese?     52 pmap_getmaps rpc problem: RPC: Unable to send; errno = Operation not permitted     53 My sles is complaining that my eth0 "start mode is manual"?     54 My sles take forever to boot     55 How do I share one of my folders with samba?     56 How do I install software on suse?     57 Mailman seems to be dropping my messages, however, I didn't see anything in the logs?     58 How to batch resize image file     59 How to setup cron to run every 5 minutes?     60 How to batch rename files? Copyright Information This article is licensed under GNU Public License. Some of the images in this article may have different copyright licenses. Please follow the URLs of the images for detailed information about their specific copyright licenses. Contact webmasters for more information on copyright issues. Linux open-source operating system [T] 1 Linux boot process Before going thru the linux boot process, it's fairly important to understand the IBM pc "real mode" memory model[MM]. When a PC boots, it runs in real mode with a 20-bit address space, or 20 address lines from/to the CPU. The maximum address from a 20-bit address space is 1M (2^20). When PC was first designed, IBM only allocates the first 640K (0x00000-0x9FFFF) to read-and-write memory (RAM). Anything beyond that is assigned to ROMs such as BIOS ROM. BIOS ROM takes the last 64k from 0xF0000 to 0xFFFFF. In this BIOS ROM space, the last command at 0xFFFF0 always points to the starting point of the BIOS instructions. Following are more details about what happens when linux boots[IBM]: BIOS-start:when the system boots, 0xFFFF0 automatically get control and starts execution. This is the end of the 1M maximum real mode memory space, and it is a JMP command to the actual bios location [CMU][[FPO] BIOS-POST: power-on self test, make sure basic IO devices are working ok BIOS-loadmbr: look thru devices in order defined by CMOS, get the first active bootable disk, and load MBR from that device. MBR is a 512byte sector on the device (sector 1 of cylinder0 head0) MBR-load boot loader: look thru partition table in MBR, find the only active partition and load its boot record (kernel loader) to RAM, and hand control over to it Kernel loader: display a list of kernels for user to select, and load zipped kernel into RAM, give control over to kernel Kernel: some hardware init Kernel: extract zipped kernel to higher RAM space, give control to the unzipped image Kernel: start() in arch/i386/boot/head.S Kernel: start_32() in arch/i386/boot/compressed/head.S Kernel: decompress_kernel() in arch/i386/boot/compressed/misc.c Kernel: start_32() in arch/i386/kernel/head.S Kernel: start_kernel() in init/main.c Kernel: cpu_idle() in init/main.c 2 Setting Up Printers on Fedora Core 4 use command printconf-gui 3 How to install chinese font on Fedora Core? yum install fonts-chinese 4 nohup nohup command: usually, when you logon to a unix system, a shell is opened for you where you can run commands etc. When you logout, all your processes will be killed except services. use the nohup command to prevent the system from killing your processes after your log out. nohup whatever-your-command-is 5 Linux partitions To show linux partitions: use /sbin/fdisk Command (m for help): m Command action a toggle a bootable flag b edit bsd disklabel c toggle the dos compatibility flag d delete a partition l list known partition types m print this menu n add a new partition o create a new empty DOS partition table p print the partition table q quit without saving changes s create a new empty Sun disklabel t change a partition's system id u change display/entry units v verify the partition table w write table to disk and exit x extra functionality (experts only) Command (m for help): p Disk /dev/hda: 120.0 GB, 120034123776 bytes 255 heads, 63 sectors/track, 14593 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/hda1 * 1 6435 51689106 83 Linux /dev/hda2 6436 10259 30716280 83 Linux /dev/hda3 10260 14083 30716280 83 Linux /dev/hda4 14084 14593 4096575 5 Extended /dev/hda5 14084 14593 4096543+ 82 Linux swap / Solaris Command (m for help): q To view current filesystems and their corresponding mount point vi /etc/fstab vi /etc/mtab 6 How Do I mount a windows share on linux via fstab : add the following line to your /etc/fstab [BY] //yourserver.yourdomain.com/storage /fileserver cifs rw,user,username=Administrator,password=xxxxxx 0 0 via command line mount //winserver/public /mnt/public -t smbfs -o username=kim,password=foo -o gid=users,dmask=777,fmask=777,rw You may need to try between smbfs and cifs on different systems 7 How to setup TwinView (Dual Head, Dual Monitor) on Fedora Core 4 7.1 Setup This procedure will surely work on the following setup, but it could work on other environments Fedora core 4, kernel 2.6.14 GeForce 6600 video card (with dual head support) Double Samsung SyncMaster 214T digital flatpanel monitors 7.2 Step 1: wire up hardware Read the manuals that came with the devices and hook them up 7.3 Step 2: download driver from nvidia website download from here 7.4 Step 3: run the setup program sh NVIDIA-Linux-x86-1.0-8178-pkg1.run 7.5 Step 4: Update your /etc/X11/xorg.conf make sure the following line are in your device section: Option "TwinView" Option "MetaModes" "1280x1024,1280x1024;1024x768,1024x768" Option "HorizSync" "DFP-0:40-70;DFP-1:40-70" Option "VertRefresh" "DFP-0:60;DFP-1:60" 7.6 Step 5: Check If something went wrong, [RTFM:ftp://download.nvidia.com/XFree86/Linux-x86/1.0-7167/README.txt] 8 How to mount ntfs file system (a windows hard drive) First check to make sure you have ntfs support by running the following commands as root: /sbin/depmod /sbin/modprobe ntfs If everything goes on well, then move on. If you see error messages, reinstall kernel to enable ntfs. Then use fdisk -l to check the device name of your hard drive: [root@localhost etc]# /sbin/fdisk -l Disk /dev/hda: 40.0 GB, 40037760000 bytes 255 heads, 63 sectors/track, 4867 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/hda1 * 1 4736 38041888+ 83 Linux /dev/hda2 4737 4867 1052257+ 82 Linux swap / Solaris Disk /dev/hdb: 80.0 GB, 80054059008 bytes 255 heads, 63 sectors/track, 9732 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/hdb1 * 1 9732 78172258+ 7 HPFS/NTFS Create a directory to mount this hard drive: mkdir /mnt/data Now that you have the device name and target directory, mount it: /sbin/mount -t /dev/hdb1 /mnt/data Or you could choose to use linux-ntfs module. 9 How to recompile the kernel First get a copy of the latest kernel source code from ftp://ftp.kernel.org/pub/linux/kernel/, decompress it, and move the whole source code directory to /usr/src/. Go into the source directory, run make menuconfig, and then make. cd dir_name make menuconfig make bzImage make modules make modules_install make install vi /etc/grub.conf 10 How to setup static ipaddress? The easiest way is to use network setup system-config-network which ever presents on your system. If you cannot find either of these on your system, ifconfig can help you temporarily change you network setup ifconfig eth0 xxx.xx.xx.xx The problem with ifconfig is that your setup is gone once your restart you system. To make permanent changes to your network setup, edit /etc/sysconfig/network/ifcfg-YOURINTERFACENAME For example[YL], put the following content in the file to use static IP address DEVICE=eth0 BOOTPROTO=static BROADCAST=XXX.XXX.XXX.255 IPADDR=XXX.XXX.XXX.XXX NETMASK=255.255.255.0 NETWORK=XXX.XXX.XXX.0 ONBOOT=yes or use the following to setup dhcp: DEVICE=eth0 ONBOOT=yes BOOTPROTO=dhcp 11 how to setup my screensaver in GNOME gnome-screensaver-preferences 12 How to set up dns server /sbin/chkconfig named on 13 How to change time zone? $ su $ ln -sf /usr/share/zoneinfo/America/Los_Angeles /etc/localtime 14 How to setup network time sync server? [root@bigboy etc]# /sbin/chkconfig ntpd on [root@bigboy etc]# /sbin/chkconfig --list ntpd [root@bigboy etc]# /sbin/service ntpd restart 15 How do I add a second disk? /sbin/fdisk /dev/sdb use n to add a new partition, w write and exit /sbin/mkfs /dev/sdb1 mount -t ext3 /dev/sdb1 /disk2 (or add a row in /etc/fstab) 16 How do I use X on my windows? Install x-win On your remote linux: export DISPLAY=your.local.windows.address:0.0 Start x app on your remote computer 17 What's the difference between nfs and samba? Usually, if you want to share disk between windows and linux, use samba. If you want to share disk between linux systems, use nfs. 18 I am using vi, how do I disable auto wrapping? :set set textwidth=0 19 How to enable auto login on linux? http://www.linfo.org/automatic_login.html For gnu desktop, use gdmsetup. If you prefer command line, look for /etc/gdm/custom.conf, under [daemon] session, add the following AutomaticLoginEnabled=true AutomaticLogin=your_user_name 20 How do I setup global variables? Use either /etc/profile or /etc/rc.local, in my case, /etc/profile worked fine 21 How do automatically run programs after a GDM autologin? Put your commands in "/etc/gdm/Xsession" 22 cannot restore segment prot after reloc SELinux is prevent you from running IDL. This can be resolved by either of the following two solutions [IV] *Change the default security context for IDL by issuing the command: chcon -t texrel_shlib_t /usr/local/rsi/idl_6.1/bin/bin.linux.x86/*.so * Disabling SELinux altogether by setting the line SELINUX=disabled in your /etc/sysconfig/selinux file. 23 How to setup timezone in linux? ln -sf /usr/share/zoneinfo/Europe/Amsterdam /etc/localtime ([wikihow] 24 boot scripts http://www.atnf.csiro.au/people/rgooch/linux/boot-scripts/ Note that in linux startup scripts, a function return 0 for success and non-0 for failures. 25 Error while loading shared libraries: libfuse.so.2 check /etc/ld.so.conf for a line containing '/usr/local/lib'. If it's missing, add it, and run ldconfig afterwards 26 Ubuntu: Root login not allowed This happens when you try to login in as root via GUI, you need to (1) remote logon from a console, or (2) somehow mount the harddisk to another linux and update /etc/ so it boots into console Then, if you still want to enable root login via GUI, do the following Login as a regular user su Option 1: run gdmsetup -> Security -> allow local admin login Option 2: edit /etc/gdm/gdm.conf or gdm.conf-custom, set AllowRoot = true 27 How to set runlevel in Ubuntu? /etc/event.d/rc-default 28 How to setup network on gentoo? /etc/conf.d/net To change host name, edit /etc/env.d/01hostname and /etc/conf.d/hostname 29 How do I mount an LVM on Ubuntu? $apt-get install lvm2 modprobe dm-mod vgscan vgchange -ay VolGroup00 lvs mkdir /tmp/aaamount /dev/VolGroup00/LogVol00 /tmp/aaa 30 How do I add a user to a specific group? If it's a new user "useradd -G ftp tony". Otherwise use "usermod -a -G ftp tony" 31 How do I autologin a user in gdm? Edit /usr/share/gdm/default.conf, locate and update the following section:[GC] [daemon] # Automatic login, if true the first local screen will automatically logged in # as user as set with AutomaticLogin key. AutomaticLoginEnable=true AutomaticLogin=username Edit /etc/gdm/custom.conf, locate and update the following lines: AutomaticLoginEnable=true Note that username cannot be root. 32 What's the initial ubuntu root password? use "sudo passwd root" to init password 33 How do I install x on linux apt-get install xorg 34 How do I kill a process by name killall -9 process-name on a side note, kill -9 only kills by process number 35 How do I install fuse? Easiest way: yum isntall kernel-devel [DH] 36 I am using Redhat Enterprise RHEL, and yum doesn't seem to be working, what do I do? Register with redhat network (RHN) and see if that helps. 37 How to change hostname? vim /etc/sysconfig/network /sbin/service inetd restart 38 I think I have the correct host:/path and mount-point, why cannot I mount an nfs share? Check and make sure that portmap and netfs services are on. If you get error "pmap_getmaps rpc problem: RPC: Unable to send; errno = Operation not permitted?", Check and make sure you firewall is off 39 Where's my lsof? I am using Redhat, and yum shows lsof as installed /usr/sbin/lsof 40 Failed to mount NFS share, reason given by server: Permission denied Check /var/log/messages on the server for more details. 41 How do I create an ext3 file system? First use fdisk to create a partition, and then use mkfs.ext3 /dev/sdxx to format file system 42 I just bought a new disk, how do I create and export a file system as NFS share? Add the new disk to your system Boot up your system, check /dev/sdxx or /dev/hdxx for your newly added disk. Use /sbin/fdisk /dev/sdx as necesary. Suppose it is /dev/sdc. /sbin/fdisk /dev/sdc, use n to create a new partition, write partition tables back to disk with w command, q to quit /usr/sbin/mkfs.ext3 /dev/sdc1 Add the following line to your /etc/fstab: /dev/sdc1 /nfs-share ext3 defaults 0 0 Add the following line to your /etc/export: "/nfs-share 10.111.0.0/255.255.0.0(rw)". By having this ip pattern, anybody from 10.111.x.x can access your share read and write /sbin/service nfs reload (/sbin/service/nfs start if it's not started already) On your client, use the following to mount the share: mount -t nfs your.server.name:/nfs-share /mount/point 43 I am using redhat and I got this error: Abuse of service deteced for server xxxx Try to re-register your rhn setup with rhn_register. 44 How do I create an ext2 file system? Use fdisk to create a new partition, then use mkfs.ext2 to format file system. 45 How do I create a non login user? adduser, then edit /etc/passwd, point shell to /sbin/nologin 46 How do I create a restricted user? cd /bin ln -s bash rbash Add /bin/rbash to /etc/shells. Then edit /etc/passwd to point to /bin/rbash instead of /bin/bash. 47 Cannot determine the version of the linux kernel source? If this happens when you are installing fuse on rehdat 4, then run "up2date -f kernel-devel", and then run fuse "configure --with-kernel=/usr/src/kernels/xxxxx/" 48 Using Ubuntu, how do I install g++? sudo apt-get install build-essential 49 I am trying to install fuse on Redhat advanced server 4, configure/make/make install went on fine, however, I kept getting "module not found error" when I do modprobe Locate that fuse.ko file, and try to insmod it. If you get compatibility error, do "uname -a" to check your kernel version, and make sure you have the correct kernel headers under /usr/src. Not that kernel-devel and kernel-smp-devel are two different modules. If you have smp in your kernel, you'll need to "up2date kernel-smp-devel". 50 I lost my Ubuntu root password, how do I reset it? Power cycle your system, press ESC at the grub menu, press e to edit grub, hight light the kernel line, and press e again. Add rw init=/bin/bash to the end of the line, and press b to reboot. You'll be in a root shell. Change passwords, and add new users as needed. 51 How do I change my locale in Ubuntu, for example to Japanese? Edit /var/lib/locales/supported.d/local, and add your language, e.g., ja_JP.UTF-8 UTF-8. dkpg-reconfigure locales Edit /etc/default/locale and /etc/environment, and add these two lines "LANG=ja_JP.UTF8", and "LANGUAGE=ja_JP:ja". Worked for Ubuntu 710. 52 pmap_getmaps rpc problem: RPC: Unable to send; errno = Operation not permitted If you get this when trying to mount an nfs share, check the following: netfs service and portmap service are started? firewall is turned off? 53 My sles is complaining that my eth0 "start mode is manual"? Check your /etc/sysconfig/network/ifcfg-eth0 and make sure it has the following line "ONBOOT=yes". 54 My sles take forever to boot Go into failsafe (debug) mode and you'll see where sles got stuck. If it's at network startup, attach your harddrive to another computer, and remove all ifcfg-ethxxx under /etc/sysconfig/network 55 How do I share one of my folders with samba? [export] comment = Public Stuff path = /your/path public = yes writable = yes printable = no create mask = 0777 Note that writable line gives access to everybody. If you can't create files from this share, you might need to chmod your shared directory? 56 How do I install software on suse? Use /sbin/YaST -> software. Optionally, point repo to your local installation disk. 57 Mailman seems to be dropping my messages, however, I didn't see anything in the logs? If you are sending messages to a maillist, remember that your mail goes thru your mail daemon first, for example, postfix. So you'll need to look at postfix logs at /etc/log/maillog. If still you don't see any useful logs, make sure your syslogd (or rsyslog) service is running properly. 58 How to batch resize image file yum install -y ImageMagick, then use mogrify command 59 How to setup cron to run every 5 minutes? Use */5 * * * * cmd FG http://www.foogazi.com/2008/04/01/quickzi-how-to-set-cron-to-run-every-5-minutes/ 60 How to batch rename files? Batch rename 1.txt to 1.TXT for file in `find . -name "1.txt"` ; do mv $file `echo $file | sed 's/\(.*\.\)txt/\1TXT/'` ; done Comments References [BY] http://kim.biyn.com/Linux/how_to_mount_samba_windows_shares_at_boot_time_via_fstab [CMU] www.cs.cmu.edu/~410/lectures/L20_Bootstrap.pdf [DH] http://devhen.wordpress.com/2006/06/08/howto-install-sshfs-on-centos-linux/ [GC] http://library.gnome.org/admin/gdm/2.20/configuration.html.en#daemonsection [IBM] http://www.ibm.com/developerworks/linux/library/l-linuxboot/ [IV] http://www.ittvis.com/services/techtip.asp?ttid=3092 [MM] http://www.dewassoc.com/support/msdos/msdos_memory.htm [T] http://www.isc.tamu.edu/~lewing/linux [YL] http://yolinux.com/TUTORIALS/LinuxTutorialNetworking.html#CONFIGFILES [[FPO] http://www.frontiernet.net/~fys/rombios.htm [wikihow] http://www.wikihow.com/Change-the-Timezone-in-Linux English-Chinese Linux [ʹÓÃÓÚPCÉϵÄunixϵͳ] (search time: 362.818 msec)