Creating a User Account for Yourself
Some Basic FreeBSD Commands
Command Line Editing
Using vi as an Editor
Short Example Using FreeBSD Commands
SSH and SCP instead of Telnet and FTP
Getting FreeBSD 4.5 Files and Others
pkg_add: Adding Packages or Ports by Hand
Stopping and Starting the Network
Stopping and Starting Services
Slices and Partitions
Quick Installation Guide (Using CD-ROM)
The FreeBSD Directory Structure
A Few Differences from Linux
Many of the topics covered in this short session will be discussed in more detail in the Monday evening FreeBSD session.
PASSWORD: Given in class
PLEASE! Do not change the root password. This will cause numerous problems throughout the workshop. The machine in front of you is yours for the duration of the workshop.
IF YOU CHANGE THIS PASSWORD YOUR MACHINE MAY BE REINSTALLED FROM SCRATCH!
adduserscript if you wish. This may require additional setup on your part the first time you run the script.
Below create the exim user account and your own personal user account as well using the following commands:
pw useradd exim -u 90
pw useradd username -m -G exim,wheel -s /usr/local/bin/bash
By placing your user in the wheel group this allows you to become the superuser root by
su command. For more information on the
pw command type
at the prompt.
|man||Help pages for commands|
|MaKe a DIRectory|
|See currently running ProceSses|
|ConCATenate a file to the screen (by default)|
|Display a file to the screen with editing functionality|
|more||Display a file to the screen and pause|
|See the end (tail) of a a file|
|gzip||ZIP (compress) a file, or set of files|
|gunzip||UNZIP (decompress) a zip archive|
|bunzip2||ZIP/UNZIP alternate compression format|
|tar||Archive/unarchive files/directories to file or tape|
|grep||Look for pattern(s) in file(s)|
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# bash bash-2.03#
If you change the default shell for root it is possible to create a situation where you cannot get a a shell if your machine's environment becomes damaged.
||-- edit a file|
||-- insert text before cursor position|
||-- append text to end of current line|
||-- delete character under cursor|
||-- delete whole line|
||-- save and exit|
||-- exit without saving|
||-- save and exit|
||-- insert a line after cursor position|
||-- delete the current line|
||-- left|down|up|right (preferred)|
However, you may find that some of this is quicker to do from the command line, some of which is explained below.
We will be placing source for programs during the workshop in a directory called /usr/local/src. The /usr partition contains enough space for us to use this for this purpose. The /usr partition, also, contains your home directories. See the Installation Notes section below for more information on partition slices.
To create /usr/local/src do the following:
Take a look at what's in /usr/local/src (which is nothing):
Note: if you are accustomed to using telnet, ssh looks almost identical and will behave the same for much of what you wish to do, but ssh has much more functionality available if you decide to use it.
Basic SSH and SCP Commands
||-- Connect to host using an encrypted session|
||-- Copy filename to path at host using username for authentication|
||-- Copy all files and all subdirectories to host under path specified. This is much more difficult using ftp.|
||-- Copy file from host authenticating with user and put it in path with filename.|
||-- Copy filename from hostX authenticating as userX to hostY authenticating as userY. This is something that you cannot do with ftp.|
cd pub/FreeBSD[to get FreeBSD 4.5 CD-ROM files]
Many third-party software is supplied in ready-to-use form, but is not in the base system. This is (a) to keep the base system smaller, and (b) because of different licensing terms. (The FreeBSD license is actually less restrictive than the GNU/GPL license under which a lot of open-source software is distributed)
All this third-party software installs under
You can use
/stand/sysinstall to add packages, but it is quicker
to use 'pkg_add' from the command line. The example below assumes that you have
the FreeBSD mounted to the mount point /cdrom. For example, to add the editor
# cd /cdrom/packages/All # ls # pkg_add joe-2.8_3.tgz [For the workshop you can simply enter in the command below. Note that you must be root to do this.] # pkg_add ftp://noc.ws.afnog.org/pub/FreeBSD/4.5-RELEASE/packages/All/joe-2.8_3.tgzNote that the configuration files for third-party software are in
/usr/local/etc, and scripts to start daemons are installed under
You can also compile packages directly from the source code, if you have the "ports" distribution installed (not installed in this workshop). The ports system automatically fetches the source file via FTP or anonCVS, applies any FreeBSD-specific patches, and compiles and installs the code. A "package" is really just a "port" which has been compiled.
# cd /usr/ports/shells/bash # make # make install # make cleanSometimes you will find that a "port" exists, but no corresponding binary "package". This is usually because of licensing or export restrictions. The "port" is always able to be distributed because it does not include any software, only instructions on how to fetch and compile the software from somewhere else.
You can query installed packages, or package .tgz files, using pkg_info.
||-- list all installed packages (one line per package)|
||-- description of package|
||-- list all files in package|
||-- read this for more details|
This is the command you use to interactively start and stop network interfaces and to define how they run. You need root access to use this command.
/etc/rc.conf. This file is edited by /stand/sysinstall, but it's perfectly OK to edit this by hand. It is in this file that you configure the hostname, IP address for each interface, and so on. Changes you make in here won't take effect until you reboot.
defaultrouter="126.96.36.199" hostname="host1.t1.ws.afnog.org" ifconfig_ed0="inet 188.8.131.52 netmask 255.255.255.248" # On hosts where you don't want sendmail to accept incoming port 25 # (but you still want daemons to be able to send outgoing mail): sendmail_flags="-q30m"
The sendmail flag is not set in this workshop. The full list of options, and their default values, can be found in /etc/defaults/rc.conf - but don't edit this file, edit /etc/rc.conf instead. This makes it easier to upgrade your system to a later version of FreeBSD.
You may be used to something like "/etc/rc.d/init.d/network stop" under Linux. Under FreeBSD this functionality resides in /etc/rc.conf and is parsed at system startup. So, to stop your currently running network first use ifconfig to figure out what interface you wish to stop.
This displays your network interface status. Notice that "ed0" (Fast Ethernet) has an IP address assigned (via DHCP). Not that lo0 as an address as well. This is your loopback device. To bring ed0 down type:
Now to bring it back up just type:
There is quite a bit more to ifconfig and we'll discuss this during the Monday evening FreeBSD session as well, or you can type "man ifconfig" for more information. Review the "rc.conf" section above as well.
By default, system services are configured in /etc/rc.conf and are started at system startup. If you need to start and stop one of these services (perhaps you changed the service's configuration file) you should do the following:
or to find a particular running service, like sendmail, try:
You'll get output that includes the process ID number on the left. If you make a change to the process's configuration, or just need to restart the process, you can do the following:
Note, if the service is a third party package, then you can often find configuration files for the service in /usr/local/etc/. In addition you may find shell scripts that can start and stop the service with command line parameters in /usr/local/etc/rc.d. Use these scripts instead, when available, to start and stop a service.
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The FreeBSD slice is then divided into "partitions". Example:
/dev/ad0 -- first ATA/ATAPI (IDE) hard drive /dev/ad0s1 -- first slice (MSDOS "partition") on first IDE hard drive /dev/ad0s1a -- first partition in this FreeBSD slice /dev/ad0s1b -- second partition in this FreeBSD slice /dev/ad0s1e -- third (usable) partitionFor historical reasons, partitions c and d are not used. We strongly recommend you configure your partitions as:
a: root filesystem (/) b: swap space e,f...: other filesystemsAll "large" parts of the filesystem should be separate from the root, so that the root itself remains small (less likely to get corrupted). This means at least /usr and /var, and possibly also /home if you have user accounts. The convention we have used is to create a resonable sized /var partition (for variable data like logs), then we have put all remaining disk space in a partition called /usr, and put home directories under that (/usr/home/username)
Insert boot floppy, change to root floppy when prompted Skip kernel config Express install Delete any existing partitions, then select "Entire disk" Say Yes to standard partition entry Select BootMgr Create partition; ctrl-U to delete number presented, enter "100m" instead FS / Create partition; ctrl-U; 100m Swap Create partition; ctrl-U; 400m FS /var Create partition; ctrl-U; 400m FS /usr Create partition; hit enter to accept number given (i.e. rest of disk) FS /u X-User (must hit SPACEBAR, not Enter, to select it) Yes install ports collection Default answers to remaining questions (i.e. just hit Enter) WAIT for install to complete No extra options after install Exit install Reboot (remember to remove floppy and CD) Login as root halt Label machine as being successfully installed.
man hierat the prompt.
The FreeBSD directory hierarchy is fundamental to obtaining an overall understanding of the system. The most important concept to grasp is that of the root directory, ``/''. This directory is the first one mounted at boot time and it contains the base system necessary to prepare the operating system for multi-user operation. The root directory also contains mount points for every other file system that you may want to mount.
A mount point is a directory where additional file systems can be grafted onto the root file system. Standard mount points include /usr, /var, /mnt, and /cdrom. These directories are usually referenced to entries in the file /etc/fstab. /etc/fstab is a table of various file systems and mount points for reference by the system. Most of the file systems in /etc/fstab are mounted automatically at boot time from the script rc(8) unless they contain the noauto option. Consult the fstab(5) manual page for more information on the format of the /etc/fstab file and the options it contains.
A complete description of the filesystem hierarchy is available in hier(7). For now, a brief overview of the most common directories will suffice.
|/||Root directory of the filesystem.|
|/bin/||User utilities fundamental to both single-user and multi-user environments.|
|/boot/||Programs and configuration files used during operating system bootstrap.|
|/boot/defaults/||Default bootstrapping configuration files; see loader.conf(5).|
|/dev/||Device nodes; see intro(4).|
|/etc/||System configuration files and scripts.|
|/etc/defaults/||Default system configuration files; see rc(8).|
|/etc/mail/||Configuration files for mail transport agents such as sendmail(8).|
|/etc/namedb/||named configuration files; see named(8).|
|/etc/periodic/||Scripts that are run daily, weekly, and monthly, via cron(8); see periodic(8).|
|/etc/ppp/||ppp configuration files; see ppp(8).|
|/mnt/||Empty directory commonly used by system administrators as a temporary mount point.|
|/proc/||Process file system; see procfs(5), mount_procfs(8).|
|/root/||Home directory for the root account.|
|/sbin/||System programs and administration utilities fundamental to both single-user and multi-user environments.|
|/stand/||Programs used in a standalone environment.|
|/tmp/||Temporary files, usually a mfs(8) memory-based filesystem (the contents of /tmp are usually NOT preserved across a system reboot).|
|/usr/||The majority of user utilities and applications.|
|/usr/bin/||Common utilities, programming tools, and applications.|
|/usr/include/||Standard C include files.|
|/usr/libdata/||Miscellaneous utility data files.|
|/usr/libexec/||System daemons & system utilities (executed by other programs).|
|/usr/local/||Local executables, libraries, etc. Also used as the default destination for the FreeBSD ports framework. Within /usr/local, the general layout sketched out by hier(7) for /usr should be used. Exceptions are the man directory is directly under /usr/local rather than under /usr/local/share. Ports documentation is in share/doc/port.|
|/usr/obj/||Architecture-specific target tree produced by building the /usr/src tree.|
|/usr/ports||The FreeBSD ports collection (optional).|
|/usr/sbin/||System daemons & system utilities (executed by users).|
|/usr/src/||BSD and/or local source files.|
|/usr/X11R6/||X11R6 distribution executables, libraries, etc (optional).|
|/var/||Multi-purpose log, temporary, transient, and spool files.|
|/var/log/||Miscellaneous system log files.|
|/var/mail/||User mailbox files.|
|/var/spool/||Miscellaneous printer and mail system spooling directories.|
|/var/tmp/||Temporary files that are kept between system reboots.|
Linux: eth0 = first ethernet device (of any type) FreeBSD: ed0 = first NE2000 device, ep0 = first 3Com 3c509, etc. Linux: COM1 serial port = /dev/ttyS0 FreeBSD: COM1 serial port = /dev/cuaa0 (call out) or /dev/ttyd0 (call in) Linux: /etc/inittab configures incoming serial connections FreeBSD: /etc/ttys configures incoming serial connections