Roaming
Computing System
Administrative Guide
Updating the server's
operating system and
software applications
Mirroring
a workstation
Adding
a new user
Adding
an email account
Adding a
new printer driver
Printers
Periodic Maintenance
Changing the passowrd of a user who has forgotten
their password
Introduction
This
information is intended for those providing computer support for an
implementation of our Roaming
Computing System. However some of this information is appropriate
for accidental administrators (perhaps something broke and there's
no-one more willing than you around).
Administrators should frequently check for updates to the changes to the Roaming Computing System
document.
Useful Software for system administration
TWEAK
(http://thegoldenear.org/tweak/)
- a script used on workstations for configuring aspects of the Roaming
Computing System.
It can be handy to save TWEAK in E: on each workstation and also in P:
on the file server.
TWIX (TWEAK Unix)
(http://thegoldenear.org/toolbox/unices/twix/)
- a script used on the file server for configuring aspects of the
Roaming Computing System.
It can be handy to save TWIX in Root's home directory (/root).
Putty (http://www.chiark.greenend.org.uk/~sgtatham/putty/)
- allows you to login to a shell on the file server from a Windows
workstation,
as though you were actually using the console at the server itself.
WinSCP (http://winscp.net/)
- a file manager that allows you to move files between the file server
and a Windows workstation and manipulate files on the file server.
Troubleshooting lost
connectivity
When you lose
connectivity somewhere in the system, there are a number
of basic places to investigate (use the network map for your
organisation to help troubleshoot networking issues):
workstations
A
network cable comes out the back of each workstation to a hub. Most
network cards have a green light to indicate that a connection has been
made to the hub, if present this will be beside the connection where
the cable plugs into the back of the computer.
file
server
This
provides the domain that users log into, which includes shared disk
space and some software applications.
Physically check it is switched on. You
can switch on the monitor (then press something like a [shift] key to
wake up the display) and see if there's a command-line.
The file server should very rarely need to be rebooted.
If you need to switch it off, you must do so by logging in as
root and issuing the 'halt'
command, or similarly rebooting it with 'restart'. Warn anyone that may
be using it that you are going to do this.
gateway/router
and firewall
This
provides
access to the Internet.
(and provides IP addresses to workstations)
Physically check it is switched on. You
can switch on the monitor (then press something like a [shift] key to
wake up the display) and see if there's a command-line.
Cycling the power on the gateway can potentially restore lost Internet
access.
You can reboot this computer or switch off its power without any
special considerations (because its operating system is running from a
floppy disk),
other than that people might be using its services
ADSL
router
(not all sites will
have one of these)
This
provides
access to the Internet.
Physically check
it is switched on. You should see lights on its front
panel, some of which will probably be flashing if it is working and the
Internet is being
used.
You can cycle
its power without any
special considerations, other than that people might be using its
services.
hub(s)
This
provides access to computers further downstream, which will probably
include the
file server, mail server and Internet (which may or may not be directly
connected to the particular hub you're looking at). A cable runs from
the back of each computer to the front panel of a hub, then a single
cable takes the connection on upstream; there may also be other cables
coming in from other hubs, depending on the size and complexity of your
network.
Cycling the power on a hub can potentially restore lost connectivity.
Physically check it is switched on. You should see lights on its front
panel, some of which will probably be flashing if it is working and the
network is being
used. Each light corresponds to an individual computer.
You can cycle the power on a hub without any special considerations
(because it is an unintelligent device), other than that
people might be using its services.
mail
server
This
provides email mailboxes and routing of incoming and outgoing email.
Physically check it is switched on. You
can switch on the monitor (then press something like a [shift] key to
wake up the display) and see if there's a Windows login screen.
If you really need to switch it off, choose 'Shut Down' from the login
screen then either 'Shut down' or 'Restart'. Warn anyone that may be
using it that you are going to do this.
If Internet connectivity is lost, it is important to login to the mail
server and pause Mercury's POP3 and SMTP processes until connectivity
is restored, as any
outgoing email will be lost and a report of its loss will not be
generated.
Troubleshooting
email problems
Mercury, the
mail transport system, is running on the mail server. To quickly check
if email is coming in from and going out onto the Internet, login to
the mail server as Administrator, double-cilck on the Mercury icon in
the Windows task tray and look at the POP3 (incoming) and SMTP
(outgoing) windows. Look for error messages.
Addresses of networked devices
Device
|
Function
|
IP
address
|
Network
name
|
| gateway
(firewall
and NAT router) |
Internet
access
|
10.0.0.1 |
?
|
| file
server |
domain;
shared disk space; email program
|
10.0.0.2 |
file-server |
mail
server
|
email
mailboxes; Mercury mail transport system
|
10.0.0.3 |
mail-server |
hub(s)
|
connect
networked devices together
|
n/a |
n/a
|
printer (1)
|
|
10.0.0.20 |
|
printer (2)
|
|
10.0.0.21 |
|
workstations
|
|
10.0.0.x
assigned
by DHCP
|
|
For more detailed
networking
information see the relevant network map.
Making
CD-ROMs available to users over the network
at the server
console, or using it remotely:
mount
a CD-ROM that is in the drive: mount /cdrom
un-mount a CD-ROM that is in the drive so that you can, for example,
replace it with another: umount /cdrom
Whilst the CD is
mounted it is available to everyone in the domain at \\FILE-SERVER\cdrom. This access is
facilitated by a section in Samba's smb.conf configuration file. If the
actual CD drive has a SCSI interface then it can be shared by a number
of people simultaneously.
[add to User Guide
section on drive mappings that \\file-server may be available. if you
want access to a CD and you haven't a CD-ROM on your workstation then
ask the administrator to enable it for you on the network).
Shutting down
servers
file servers
- make sure nobody is using it
- login as root
- type 'halt'
and press enter
firewall and NAT
routers
- for those
running FloppyFW, just switch off the power
Restarting
the file-server or it's services
restart the server: reboot
restart Samba: /etc/init.d/samba
restart
restart networking: /etc/init.d/networking
restart
If
you're going to restart the server or its networking or Samba services,
make sure no-one is using it in any and all locations that workstations
are situated in.
Updating the
server's operating system and
software applications
To update its stable software distribution with any available fixes for
security and data-loss bugs released since last it was installed or
updated:
apt-get
update
apt-get dist-upgrade
Mirroring
a workstation
Those
workstations consisting of exactly the same hardware (there are some
exceptions) can be copied disk-to-disk if required. The procedure for
doing so is:
- take the hard drive from the workstation you're copying to and
install on the secondary channel in the workstation you're copying from
- you may have to auto-detect hard disks so that the BIOS is aware
of the new hard disk
- change the BIOS to boot from the floppy disk
- boot into Partition Magic
- copy C: from disk 1 to disk 2
- copy D: from disk 1 to disk 2
- convert D: from primary to logical (this step takes longer than
the others)
- you can copy E: and F: and
convert them to logical also, or you can just create those drives
within
Partition Magic and use the Automatic Toolbox Engineering to configure
them once you have the new hard disk installed in the workstation
(using
'create directories per-machine' - B; create directories for
administrator - L; and system settings(? - in-case anything has changed
in ATE)
- make sure disk 2 is marked active
- reboot the machine; switch it off; remove disk 2; restore the
first boot device to be the first hard disk
- switch on the newly configured workstation, without a network
cable attached
- change the workstation's name and make it part of some fictitious
workgroup, rather than the existing domain
- reboot and join it to the domain
- run Automatic Toolbox Engineering system settings option (D) as
Windows' logon option of pressing ctrl+alt+del will have been enabled
by
joining the domain
- if it has an optical media drive and the workstation it was
copied from did not then change that drive letter to Z:
- make any changes required specific to this workstation (such as
pointing to a different printer or CD writer software)
Be sure to apply
the changes in Partition Magic after every step, rather than allowing
them to queue up, as problems can sometimes occur if you do.
Adding a new user
See the document entitled 'Creating system and email accounts for
users'.
Adding
an email account
From within
Mercury, choose:
- Configuration -> Manage local users...
- Add
- enter a Username
- enter a Personal name (we're currently using username@domain-name.tld but it could
perhaps be their actual personal
name)
- if alias or synonyms need to be created then add them but this
isn't the norm
Using Pegasus
Mail:
- load up
Pegasus
Mail and go into the new account then quit
- pre-configure
the Pegasus Mail settings by copying over a template copy of their
PMAIL.INI file from \\MAIL-SERVER\MAIL to their mailbox directory,
replacing the existing one
- globally
replace
all instances of the username from that template PMAIL.INI with the new
username
Adding a
new printer
driver
HP
LaserJet 4, 5, 6 series
Login locally as
Administrator.
Choose Start
-> Settings -> Printers -> Add Printer.
Follow the
instructions in the 'printer driver configuration' section of the Printer
Configuration
document for
the 'HP LaserJet 4,5,6 PCL5e driver (2.0.12.2)'.
(When logged in
as Administrator you don't have access to P: so must explicitly point
the printer driver to the directory on the server with the driver in.
This directory should be something like
\\FILE-SERVER\PROGRAMS\drivers\4,5,6 PCL5e 2.12.02 (en-us) [2k,xp]. It
will possibly be easier to navigate to that directory using Windows
Explorer before trying to add the printer driver and copying the
directory name from the location bar into the paste buffer so that it
can be pasted into the printer driver file picker
Printers
Periodic maintenance
- Defragment
all
hard drives on workstations periodically, for best performance ('Start -> .Programs -> Accessories -> System
-> Defragment')
- Remove
backups left by Windows Automatic Updates (when Microsoft Service
Packs, hotfixes or certain security updates are installed)
from directories
%WINDIR%\NtUninstallKxxxxxx$
Changing the password of a user who has
forgotten their password
- Login to
the server console as root
- Change
their UNIX password:
passwd
<username>
- Change
their Samba password:
smbpasswd -a
<username>