System Administration Course Addendum

Additional Notes to Specific Modules

Additional Literature References

Maurice J. Bach: The Design of the UNIX Operating System, Prentice-Hall, 1986.

Evi Nemeth, Garth Snyder, Scott Seebass: UNIX System Administration Handbook, Prentice Hall, 2nd edition, January 1995. ISBN 0131510517.

Brian W. Kernighan and Rob Pike: The UNIX Programming Environment, Prentice Hall, 1984.

Berny Goodheart and James Cox: The Magic Garden Explained - The Internals of UNIX System V Release 4, Prentice Hall, 1994.

Curt Schimmel: UNIX Systems for Modern Architectures - Symmetric Multiprocessing and Caching for Kernel Programmers, Addison-Wesley, 1994.

Hal Stern: Managing NFS and NIS, A Nutshell Handbook, O'Reilly & Associates, Inc., 1991.

Notable WWW References

www-europe.sgi.com is the European mirror site for www.sgi.com. i.e., all references to www.sgi.com can be replaced by www-europe.sgi.com. Below, only the references to the main site (www.sgi.com) are listed.

• Education Services: http://www.sgi.com/support/custeducation/
• Free licenses (MPEG, Cinepak Encoder) http://www.sgi.com/support/licensing/free_licenses.html
• Download Cool Software: http://www.sgi.com/products/evaluation/
• Freeware for System Administrators http://www.sgi.com/fun/freeware/sysadmin.html
• Frequently Asked Questions on SGI http://www.sgi.com/misc/feedback_faq.html
• Insider Newsletter http://www.sgi.com/insider/index.html
• Pipeline technical support publication: http://www.sgi.com/support/pipeline.html
• Public Domain Software for the SGI Platform http://reality.sgi.com/billh/anonftp/

All Modules

• IRIX 6.5 http://www.sgi.com/software/irix6.5/
• IRIX Developers Home http://www.sgi.com/developers/technology/irix/index.html
• The SGI IRIX 6.5/MIPS Roadmap http://www.sgi.com/developers/feature/2000/Roadmap.pdf
• IRIX 6.5 Frequently Asked Questions (FAQ) http://www.sgi.com/developers/technology/65faq.html
• IRIX 6.2 Technical Report http://www.sgi.com/Technology/IRIX6.2/irix6.2TR.html XXXX
• IRIX 6.4 Technical Report http://www.sgi.com/Technology/Irix6.4/cellular_irix6.4tr.html XXXX
• SGI admin Frequently Asked Questions (FAQ) http://www.sgi.com/Archive/FAQs/admin/ XXXX
• Frequently asked Questions on any topic http://www.sgi.com/tech/faq/ XXXX

Module 2 - System Setup

• Technical Specifications of SGI Products: http://www.sgi.com/Technology/dev-resources2.html#prods XXXX
• Connectivity Technical Archives: http://www.sgi.com/tech/connectivity.html XXXX
• Indy, Internet, PC/Mac Connectivity: http://www.sgi.com/Technology/Connectivity/Connectivity.html XXXX

Module 3 - System Documentation

• Technical Publications Library (online books): http://techpubs.sgi.com/library/
• Silicon Graphics Online Help and Documentation Environment http://www.sgi.com/Technology/tech_InSight.html XXXX

Module 4 - User Support

• Silicon Graphics Security Headquarters http://www.sgi.com/support/security/

Module 5 - System Monitoring

• Performance Co-Pilot (PCP) http://www.sgi.com/software/co-pilot/

Module 7 - Filesystems

• XFS - File System http://www.sgi.com/software/xfs/index.html

Module 8 - Logical Volume Management

Module 11 - Backup and Restore Tools

• Applications Directory: Data Management: http://www.sgi.com/products/appsdirectory.dir/SolutionIXData_Management.html
• Silicon Graphics ccNUMA Origin Servers First to Break Terabyte Data Sort Barrier http://www.sgi.com/newsroom/press_releases/1997/december/sorting_release.html
• OriginTM 2000 One-Terabyte Per Hour Backup White Paper http://www.sgi.com/origin/2000/terabyte.html
• Record-Setting Restore Time for a One-Terabyte Database http://www.sgi.com/features/1998/nov/restore/index.html

Module 13 - Software Installation

• SGI software patches http://www.sgi.com/support/patch_intro.html

Appendix B - Manual PrinterConfiguration

• IRIS Impressario - A Printing and Scanning Framework: http://www.sgi.com/software/impressario/index.html
• Supported printers with Impressario http://www.sgi.com/software/impressario/tech_info2.html

Additional Notes to Specific Modules

Some useful hints, caveats, not necessarily found in the course handouts. These notes are meant to be accompanying the course handouts and may or may not be useful without them.

Module 2 - System Setup

• set the time zone for Central Europe to (in /etc/TIMEZONE):

• to specify a year >= 2000, the century (cc) needs to be specified. To establish a date of 12 Oct 2004, 11:04 a.m.:

• The netmask is a bit pattern that defines the directly addressable hosts in a local subnet, e.g., 0xffffff00 (equivalent to 255.255.255.0). All hosts with the same first 3 numbers of the IP-address can be addressed directly and must, therefore, be in the local subnet. The netmask is set in the file /etc/config/ifconfig-1.options:

• The IP address, netmask, and broadcast address of a network interface can be verified by the following commands:

• To enforce a specific host resolution order, e.g., local host file first, change the following line in /etc/nsswitch.conf:

and execute the following command to activate the change:

Module 3 - System Documentation

• side-by-side view option of insight gives a much easier to use layout.
• dynaweb on Irix 6.3 requires the following product versions (or later) to be operational:

Module 4 - User Support

• Beware when recursively changing ownership of an existing user home directory (or any other directory). If it contains symbolic links, the file the link points to will get the new ownership, NOT the link. Thus, it's safer to use the -h option. This will change the ownership of the link itself:

• .auxchestrc: sample menu file in /usr/lib/X11/system.chestrc
• cpeople is not supported in releases after Irix 6.2.
• use the rwall(1) command to reach users logged on remote hosts:

Module 5 - System Monitoring

• To find disk files larger than 10000 blocks and list them in long format:

• Process table sorted by PID makes it easy to find parent processes:

• to change the size of the process table, use systune:

  # systune -i
  Updates will be made to running system and /unix.install
  
  systune-> nproc = 1000
   nproc = 303 (0x12f)
   Do you really want to change nproc to 1000 (0x3e8)? (y/n) y
  
  In order for the change in parameter nproc to become effective,
  reboot the system 
  
  systune-> quit
  

• you can configure SYSLOG=ALL in the file /etc/default/login to get all login attempts logged, whether successful or not.
• the crontab command also supports the -e option to edit the currently installed crontab file. Need to set the EDITOR variable first:

• xhost default settings:
  • 6.2 and earlier: access control disabled, clients can connect from any host (equivalent to xhost +)
  • 6.3 and later: access control enabled, only authorized clients can connect (equivalent to xhost -)

Module 6 - Disk Partitioning

• one line commands for dvhtool to list contents of volume header (for system disk and optional disk)

• xdkm, a graphical tool for creating and managing disk partitions, requires following subsystems (from IRIX CD) that are not installed by default:
  • eoe.sw.xfsmcli       XFSM Client Software
  • eoe.sw.xfsmserv     XFSM Server Software
• when new disk device files are created with mknod, don't forget to change the permissions appropriately (to read - write - execute protected for all other users):

repeat the same for the raw device /dev/rdsk/dks0d2s3.

Module 7 - Filesystems

• To simplify adding new entries to /etc/fstab, first mount thew new partitions manually, then use the command mount -p to get a list of all mounted file systems. This will be in the same format as /etc/fstab. Use copy/paste to add the new entries to /etc/fstab. To automatically add the last mounted filesystem to fstab:

• xfsm,a graphical tool for managing XFS filesystems, requires following subsystems that are not installed by default:
  • eoe.sw.xfsmcli       XFSM Client Software
  • eoe.sw.xfsmserv     XFSM Server Software
• manually mount CD-ROMs (in case mediad didn't react):
  • mount an SGI software distribution disk (contains an EFS filesystem on partition 7):

• mount an ISO 9660 type CD-ROM:

Module 8 - Logical Volume Management

• xfs_growfs can also be used on a regular disk partition, for example if a partition has been enlarged while retaining the same starting block. See also xfs_growfs(1m).
• xlvm, a graphical tool for creating and managing logical volumes, requires installation of eoe.sw.xfsmcli and eoe.sw.xfsmserv.
• Example xlv_make scripts:

vol mirrored
data
plex
ve /dev/dsk/dks1d1s7
plex
ve /dev/dsk/dks1d2s7
end

vol striped
data
plex
ve -stripe /dev/dsk/dks1d1s7 /dev/dsk/dks1d2s7
end

vol striped_and_mirrored_with_mirrored_log
data
plex
ve -stripe dks3d1s7 dks4d1s7 dks3d2s7 dks4d2s7
plex
ve -stripe dks4d3s7 dks3d3s7 dks4d4s7 dks3d4s7
log
plex
ve dks1d1s15
plex
ve dks1d3s15
end

Note: if several controllers are available for striped volumes, rotate first the controller numbers and then the disk id's for optimal performance:

GOOD:      dks3d1s7 dks4d1s7 dks3d2s7 dks4d2s7
NOT GOOD:  dks3d1s7 dks3d2s7 dks4d1s7 dks4d2s7

Module 9 - System Startup and Shutdown

• there is a man page for the PROM monitor: prom(1M)
• to boot from an alternative system disk, change the following variables in the PROM command monitor:

• to exit sash, type CTRL-D or click teh "Done" button
• boot fx from CDROM (assuming controller 0, scsi id 4):

• to boot from a remote CD-ROM, it's convenient to add /CDROM path to the tftp line in /etc/inetd.conf:

  tftp dgram udp wait guest /usr/etc/tftpd tftpd -s /usr/local/boot 
  /usr/etc/boot /CDROM 
  

• after changing /etc/inetd.conf, send a hang-up signal to the inetd process to re-examine /etc/inetd.conf:

• boot fx from a remote CD-ROM (server name is happy):

• the shutdown command has a bug (feature?). If -g<graceperiod> is specified (default: 60), shutdown waits the specified number of seconds and issues a message that the system is going down. Then, it will wait again for the same number of seconds before starting the shutdown procedure due to a sleep command in the shutdown script. Use

to get rid of it and initiate the shutdown immediately.

• if the graphics console of a system seems frozen, you can try to restart the X window server before rebooting by pressing the following keys all-together:

Module 10 - IRIX Run Levels

• to create your own run-level scripts, e.g., local networking setups:
  • create a file /etc/init.d/network.local using the following skeleton (or a copy of /etc/init.d/lp which is quite a simple one):

    #! /sbin/sh
    
    IS_ON=/etc/chkconfig
    
    if $IS_ON verbose; then
            ECHO=echo
    else
            # For a quiet startup and shutdown
            ECHO=:
    fi
    
    case "$1" in
      'start')
           if $IS_ON network; then
                   <put your commands to start programs here>     
           ;;
    
      'stop')
           <put your commands to stop programs here>
           ;;
    
      *)
           echo "usage: $0 {start|stop}"
           ;;
    esac
    

  • create links in /etc/rc2.d and (if necessary) in /etc/rc0.d:

    ln -s /etc/init.d/network.local /etc/rc2.d/S31network 
    ln -s /etc/init.d/network.local /etc/rc0.d/K39network 
    

• if using your own chkconfig flag, force initialization:

Module 11 - Backup and Restore Tools

• use of remote tapes: need to allow remote logins without passwords. Create the file ~/.rhosts and add all hosts that are allowed to login. See also rhosts(4).
• copy system disks:
  • partition the new disk such that all filesystems will fit
  • create new root filesystem and mount it (assuming new disk is on controller 0 with scsi id 2):
    • mkfs /dev/dsk/dks0d2s0
    • mkdir /newroot
    • mount /dev/dsk/dks0d2s0 /newroot
  • copy the root filesystem
    • for XFS: xfsdump -J -v silent - / | xfsrestore - /newroot
    • for EFS: dump 0f - / | (cd /newroot; restore xf -)
  • copy all the other filesystems accordingly.
  • copy the the standalone shell (sash) that is located in the volume header:
    • cd /tmp
    • dvhtool -v get sash sash
    • dvhtool -v add sash sash /dev/rdsk/dks0d2vh

Module 13 - Installing Software

• keep all and remove all
  • keep all removes all markers
  • remove all removes all markers plus all installed software that appears also on the distribution
• further useful keywords: all, default
• to install all installable software (i.e., select all subsystems marked A): install A
• to install only the upgrades for a specific product: install eoe U
• default user for remote distribution is guest
• the command "versions changed" is equivalent to "showfiles -cCH"
• copy a CDROM to a distribution directory:

• useful commands to verify installed software:
  • list all installed software including subsystems not installed by default:
    
    versions -a              showprods -a
    
  • brief listing of installed products:
    
    versions -b              showprods -D 1
    
  • list products on a CDROM distribution:
    
    showprods -f /CDROM/dist
    
  • list files belonging to a specific product (or subsystem):
    
    showfiles eoe.sw.uucp
    
  • find out to what subsystem a file belongs:
    
    showfiles -- libdmedia.so.1
    f 50334 540288 dmedia_eoe.sw.lib usr/lib/libdmedia.so.1
    l 0 0 dmedia_eoe.sw.lib m usr/lib32/libdmedia.so.1
    f 59525 570684 dmedia_eoe.sw.lib usr/lib32/mips3/libdmedia.so.1
    f 41529 557060 dmedia_eoe.sw.lib usr/lib32/mips4/libdmedia.so.1

Appendix B- Manual Printer Configuration

Printers

• the Berkeley lpd software is not installed by default. Install the following subsystems fron the newest IRIX 6.X Applications CD:
  • print.man.bsdlpr
  • print.man.bsdlpr
• further debugging hints for lp:
  • to restart the lp scheduler, you can also cycle the lp script:

• on the server (and client) use the command ps -fu lp, to check what processes are currently executing and possibly blocking the printing. You might want to kill them with kill -9 <PID>.
• some hints for using snapshot:
  • to move the snapshot icon, use ALT + RIGHT MOUSE and select Move or type ALT + F7 to get into move mode.
  • to select regions outside the snapshot icon, you need to move the camera cursor outside the icon. Press the SHIFT key and keep it pressed while moving the cursor and defining the region.
• to convert RGB files to PostScript, it's more convenient to use showcase. Use the Import->Image menu to load RGB images. You can print directly from showcase or save the page as PostScript.
• the Printer Manager offers more printer models and makes it easy to configure a printer with a network card. Make sure you have the latest Impressario software installed:
  • 5.3: Printers with network card not supported.
  • 6.2: Impressario 2.1+ (on Irix 6.2 Applications August 1996 CD or later)
  • 6.3: Impressario 2.1.2+ (on Irix 6.3 Applications CD, November 1996 or later)
  • 6.4: Impressario 2.1.2+ (on Irix 6.4 Applications CD, February 1997 or later)

Terminals

• connector types and pin-outs are documented in the serial(7) man page.
• a system can be used as a terminal to monitor a server system
  • install eoe.sw.uucp
  • configure port 2 as a modem port using the System Manager (continue with: 5.3/6.2: Port Setup, 6.3+: Hardware and Devices, then Serial Device Manager) or
    edit the file /etc/uucp/Devices and uncomment (remove the # character) the following line:
    • # Direct ttyd2 - 9600 direct
  • connect serial port 2 of your system to port 1 of the server
  • open a unix shell and issue the following command:

    cu -l ttyd2 
    

  • to exit the cu program, type ~.<RETURN>

From older versions of the system administration course

Module 9 - Introduction to NFS

• File Serving Overview: http://www.sgi.com/apps/file_serving/index.html

Module 8 - Swap Administration

• Swap space can also be configured/added using the System Manager:
  • 6.2: choose Swap Manager
  • 6.3+: choose System Performance -> Swap Manager
    • "Add Real Swap Space" uses a local file as swap space
• Virtual swap space is well explained in the swap(1m) man page

Module 9 - Network Filesystems

• mount options are in fstab(4)
• On a mounted filesystem, each NFS request waits timeo=n tenths of a second (default = 11) for a response. If no response arrives, the time-out is multiplied by 2, up to a maximum of MAXTIMO (900), and the request is retransmitted. When retrans=n retransmissions (default = 5) have been sent with no reply a soft mounted filesystem returns an error on the request. Default wait time is, therefore, 1.1 + 2.2 + 4.4 + 8.8 + 17.6 = 34.1 seconds.