Config File Overview

• Configuration for X server

• Local mailing lists
• Lines in the format:

  listname: recipient1, recipient2, ...

• List then becomes listname@yourmachine.mit.edu
• After making changes, run newaliases
• May not actually work with current sendmail.cf

• Global scripts run on login (which one depends on user's shell)

• Specifies commands to be run on regular intervals
• Highly recommended that you commend out (put hash characters at the beginning of lines) for all lines after the "# Trim wtmp" line
• Defaults to running things late at night (around 1 to 3 am)

• Directories being exported via NFS
• Exporting files via NFS opens MANY security holes

• Specifies which filesystems to mount on boot up
• Easiest to use graphical tool off of control-panel to edit
• The following mounts the ext2 partition /dev/sda2 onto /u2 :

  /dev/sda2   /u1    ext2  defaults 1 1

• The following mounts the DOS vfat partition /dev/sda4 onto /dosc and makes it so that only the user with UID 1008 can read and write files on it:

  /dev/sda4   /dosc  vfat  defaults,uid=1008,gid=0,umask=077 2 2

• The following allows any user to mount the cdrom onto /cdrom:

  /dev/cdrom  /cdrom iso9660 ro,user,unhide,exec,nosuid,nodev,noauto 0 0

• More information in mount and fstab man pages
• Using mount -a will try to mount everything in fstab
• Mount files individually with mount command:

  mount -t iso9660 -o ro,nosuid /dev/cdrom /cdrom

• The directory that the filesystem is being mounted onto must be an existing directory

• ftpd config files

• Group memberships
• Updated by Athenaized login

• Config files for tcp wrappers
• Allow you to specify which machines can finger at your machine
• For more info: man 5 hosts_access

• Directory containing web server config files

• Config file for inetd
• Listens on ports and starts things like finger and telnet and ftp

• Specifies what gets run when machine boots up
• "Runlevel" describes what system services are running
• Single user mode has minimal things running. Boot with linux single to get to this.
• Change runlevel with telinit N command

• Specifies where to look for shared libraries
• Run ldconfig as root after changing

• Config file for lilo, the boot loader
• Use to configure lilo then install changes by running lilo

• If noremote exists, users not in /etc/passwd can't login from remote
• If nocreate exists, users not in /etc/passwd can't log in at xlogin

• Lists of users, their passwords, and their home directories
• Contains colon separated fields

• Printer config file
• Edit using printtool under X as root

• Directory containing files to get run on booting up and changing runlevels
• /etc/rc.d/init.d contains files which can be run with either a start or a stop option to start and stop the services
• /etc/rc.d/rcN.d directories contain symlinks to scripts in init.d where N is the runlevel
• Put your own stuff in /etc/rc.d/rc.local

• Config file for mail distribution system
• Don't try to edit by hand

• Provides service name to port number mappings

• Config file for SAMBA which allows you to share files to Windows 3.11, 95, and NT machines
• Defaults to give write access in /tmp (!!!)

• Where RedHat's tools store information about things like your network configuration
• Use control-panel to edit

• Changes syslogging configuration
• Adding the line:

  *.*                         /dev/console

  causes messages to go to console.
• Note that spaces must all be tabs

Previous
Next
Back to the IAP Linux Page...