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Collected by the IT/User Support Team
This is a collection of Questions & Answers that have been treated by the Computing Help Desk managed by the User Support group.
N.B. The number in parenthesis refers to problem registration
at URL
http://consult.cern.ch/qa/NNNN
where NNNN is the problem identifier (number).
Question - M/S "Windows" symbol
(0081)
I have a modern PC keyboard which has a key with the M/S
"Windows" symbol on it. It is beneath the 'space'
and
'alt'
key. What is it good for?
Answer - It is a 'program function' or 'shortcut' key, which lets you rapidly execute some program or call up some functions.
Note that this key is NOT available on all standard keyboards.
Here is a list of available functions:
Win Key (WK) : ============== WK + E Open/Ouvrir [Explorer] WK + R Open/Ouvrir [command Run] WK + Pause Open/Ouvrir [System Properties] WK + F Display/Afficher [Find: All Files] WK + Ctrl + F Display/Afficher [Find : Computer] WK + M Minimize/Minimiser active windows WK + Shift + M Discard/Annuler Minimize active windows WK + Tab Go through/Circuler dans la Barre de Tâches [task bar] WK + F1 ou F1 Display/Afficher [Help Windows]
Question - Error messages from Doctor
Watson (0084)
When I launch various PC applications, I keep getting error
messages from Doctor Watson. What does this mean? Who
is this doctor?
Answer - Dr. Watson is a problem report generator that kicks in when an application does something really bad. In general it means troubles, like memory problems.
If the user is running a standard NICE PC, the only reason for this to happen is a hardware problem. It can be anything from a faulty memory card to a dead processor fan with the heat rising on the motherboard.
If "rechecking everything" fails, the next option is to reinstall the system. If even this fails, it definitely is a hardware problem and the user must contact his normal PC support team, or the original supplier (for example the IT PC Desktop Service if the PC was originally purchased there).
Question - passwords (0103)
I have changed my password but it only works on W95, not on NT.
Aren't they synchronised? The error message I get is: "Your
password change request HAS NOT been processed because of an
internal error. Please try again later."
Answer - This happens when a user's password is too long. It can be considered as a 'bug' in NT. NT only allows a maximum of 15 characters. The user must not use more than this maximum.
Question - "Application log file full"
(0105)
Under Windows NT, I get the message: "Application log file full"
What can I do?
Answer - This log is part of the NT
event viewer. To clear it, go from 'programs'
into
'administrative tools'
, then 'event
viewer'
. Before you clear the log and to be on the safe
side, save the old one as whatever you want (e.g.
oldfile
).
Note: You have to be logged as Administrator to do this.
Question - Automatically Adjust Clock
(0092)
If you are on a network which operating system has the
functionality of adjusting for changes in daylight savings time,
there will be a problem if you also use the Automatically Adjust
Clock for Daylight Savings Time Changes feature in Windows 95,
particularly if all workstations on the network are either not
using Windows 95 or have disabled this feature in Control
Panel, Date/Time, Time Zone tab.
If you allow the network operating system as well as Windows 95 to adjust for these changes, then you are no longer synchronized with the rest of the network and entries made into other users' schedules will be changed to try to adjust for this.
The following is an example of a Schedule+ problem
that has been encountered: a Windows 95 user used Schedule+
to schedule meetings on a Novell network, running Windows 95 and
Office 95. The other workstations are running Windows for
Workgroups. The network operating system had adjusted all clocks on
the system when there was a change between daylight saving time and
eastern standard time. When the Windows 95 user was asked if he or
she wanted to have Windows 95 automatically adjust for changing the
clocks, the user chose "Yes"
. After this, all other
schedules on the network that had meetings scheduled, prior to the
time change, for 1:00 P.M. found that the time has now been changed
to 2:00 P.M.
Explanation: if the network operating system adjusts the time and then Windows 95 adjusts the time, the Windows 95 machine is no longer synchronized with the other machines on the network. It has actually had its time set back by one hour twice. The workstation appears to be in a different time zone than the rest of the machines. In an effort to synchronize the times, the scheduled appointment times change.
Answer - To avoid this problem, choose
Date/Time
from the Control Panel. In the Time
Zone tab
, disable Automatically adjust clock
for daylight savings time changes.
More information : If you click the question mark (?) on
Automatically adjust clock
for daylight savings time
changes, you get an explanation of the feature as well as the
following warning: If you use more than one operating system, make
sure that only one of then adjusts for daylight saving
time.
See also the question on AFS clock skew on UNIX
.
N.B. The two following questions ("Deactivate screen
saver" and "'pagefile.sys'
file")
imply manipulations of the registry; please note that USERS
MUST UNDERSTAND WHAT they do before changing any value! (Or undesired
side effects - that maybe difficult to debug even by the
NICE experts - may occur afterwards).
Question - Deactivate screen saver
(0087)
When a password protected screen saver starts, is it possible to
get some grace period before a password needs to be entered to
deactivate?
Answer - Yes it is. Although not set by default in NICE, this can be changed as follows:
1. Start the registry editor (regedit.exe) 2. Move to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows (or Windows NT)\CurrentVersion\Winlogon 3. From the edit menu select New - String Value 4. Enter a name of ScreenSaverGracePeriod and press Enter 5. Double click and set to the number of seconds grace period. Click ok. 6. Close the registry editor 7. Reboot the machine
Question - 'pagefile.sys'
file (0093)
I have recently ran short on disk space on my hard drive on NT. By
inspecting files I discovered a huge (in my case over 40MB) file
called 'pagefile.sys'
. Is it possible to safely delete
or at least shrink this file?
Answer - During an NT session, it is not possible to access or open this system file. However, it can be shrunk/cleaned by this procedure:
regedt32.exe
or
regedit
)
ClearPageFileAtShutdown
to 1. (This key is in
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session
Manager\Memory Management
)Value Name: ClearPageFileAtShutdown Value type: REG_DWORD Value: 1You have to reboot your NT machine after these changes.
N.B.: On an extremely full hard drive, it may be necessary to reduce the virtual memory size to a value less than the drive space available:
- Control panel - system - performance - virtual memory.
Question - AFS Cache (0086)
When listing the directory content on 2 different nodes of the
ATLAS server I got 2 different versions (one missing the latest
corrections):
atlas03 > rsh atlas02 ll /afs/cern.ch/atlas/users/pop/work7/MuonIdentification/src/MuonIdNtuple.cxx -rw-r--r-- 1 pop zp 13390 Mar 26 14:06 atlas03 > rsh atlas03 ll /afs/cern.ch/atlas/users/pop/work7/MuonIdentification/src/MuonIdNtuple.cxx -rw-r--r-- 1 pop zp 13197 Mar 21 19:41What can be done?
Answer - You can rectify this abnormal
situation with the command "fs flush"
which forces the
AFS Cache Manager to remove each specified directory or file from
its cache of data and status information. The result is that the
next time data from a flushed directory or file is requested, the
Cache Manager contacts the File Server for the most current
version, along with a new callback (if necessary) and associated
status information. This command does not discard data from
application program buffers or data that has been altered in the
cache but not yet written back to the central copy maintained by
the File Server.
You can get all details regarding this AFS command with
"man fs_flush"
.
Question - Work Group Server
(0094)
Where to get all information (responsible, user guide,
configuration details, performance reports, etc.) on a specific
Work Group Server ? (e.g. THWGS, CMS, ATLAS, ALICE, CHORUS, NA48,
NA49, TIS.)
Answer - See URL
http://wwwinfo.cern.ch/pdp/bis/main/experiments.html
It will give you links, name of "Local" and "IT" contact person,
and the mailing list corresponding to the Work Group Server for all
experiments.
Question - fs sysname
(0097)
On RSPLUS the 2 commands "fs sysname"
and
"uname -r"
(or "uname -a"
) give different
information:
[rsplus11] ~ > fs sysname Current sysname is 'rs_aix42' [rsplus11] ~ > uname -r 3 [rsplus11] ~ > uname -a AIX rsplus11 3 4 001520FD4C00(for AIX 4.3).
Why ?
Answer - The AFS "sysname" command is a
relatively ad hoc constructions used basically to discriminate
between different AFS binaries. It is used because it is
automatically translated from "@sys" when used in an AFS path.
However the exact "system release" is effectively given by the UNIX
command "uname -r"
.
Question - StarOffice (Word, Excel and
Powerpoint) (0100)
I would like to use the utility StarOffice, is it available at
CERN through AFS ?
Answer - We know that many users are interested by this product which contains Word , Excel and Powerpoint 97 look-alikes. CERN is currently negotiating to have a site-wide licence and expects to have something in place shortly.
N.B. First versions will be for Solaris and Linux. Both Word and Excel utilities are fairly well compatable with the PC/Mac versions but the Powerpoint version is not able to re-transfer files from Linux/Solaris back to PC or Mac, although it can read them. In the future there maybe versions available for HP but not until end 1999 at earliest.
Question - 'AFS clock skew' problem
(0102)
I installed the Transarc AFS client for NT and wanted to get an
AFS token afterwards with afs_auth.exe
but I got the
following error message:
"server and client clocks are badly skewed."I use GMT+1:00 for the time zone. Do you know how to solve this problem?
Answer - The 'AFS clock skew' problem has been seen elsewhere on several occasions, fortunately in all cases it has come down to the same quirk in Windows/NT setup:
See also the question on Automatically Adjust Clock for PCs.
Question - Print national characters
(0101)
I would like to print a text file containing national characters ?
When using xprint
I only get strange symbols, what
should I do ?
Answer -
You can use a2ps
to print such files,
eg:
a2ps -P 513-us filename
xprint
is converting text files to postscript by
using internally an older version of a2ps
. This
version doesn't handle national characters properly. It is planned
to update xprint in the future.
Question - escape key on NCD terminal
(0088)
I'm using a NCD terminal, and there is at least one key (escape)
that doesn't work properly. I don't mean that the key is
mechanically bad, it just does not do what is supposed to do. How
do I fix it?
Answer - If you have no pure
"Esc"
key and have F11
key labeled also
(Esc)
you can assign "Esc"
value to this key
just issuing command:
xmodmap -e "keysym F11 = Escape"Then put this command in some startup
rc-file
.
Question - Ethernet address
(0091)
What is the "Ethernet address" of a machine and how to find it?
Answer - The ethernet address is 12 hexadecimal (0-9, A-F) digits, of which the first six specify the maker of the interface and the last six are unique. On some systems this address is already printed on a label, either outside the system or inside on the interface card which has the network connector.
On a PC running Windows 95 there is normally a Control Panel
program (menu Start - Settings - Control Panel
) called
"TCP/IP". Executing this shows a window giving the IP address and
name, plus a small icon labelled "View Details". Clicking on this
small icon should then give a second window including a field
called Adapter Address, which specifies the ethernet Adapter
Address.
For a PC running NT it is necessary first to open a Command
Prompt window. On a NICE NT PC this is in "PROGRAMS" in the START
menu. The command "wntipcfg"
will then normally give
the same window as for the Windows 95 PC, including the ethernet
Adapter Address. If this "wntipcfg" command is unknown (perhaps
because the NT is stand-alone) an alternative command is "net
config work", which will produce a line like
Workstation active on NetBT_IEEPRO1 (Adapter Address)On Unix systems the address is indicated at boot time. It may also be possible to run one of the following commands
'netstat -i' (on IBM AIX and DEC : needs the interface running!) '/usr/sbin/lscfg -v' (on AIX) 'dmesg" (on Linux and Solaris : normally in /usr/sbin) 'lanscan' (on HP/UX : normally in /usr/sbin)For a PC running Linux the ethernet address is written at startup time into a log file: normally
/var/log/syslog
or /var/log/messages
.
On a recent Macintosh there is a Control Panel program called "TCPIP". Executing this shows a window giving the IP address. When this is visible there is an item in the "File" menu called "Show Info". Using this will normally give a separate window showing the ethernet address. If it does not then you have an old version of what is now called "Open Transport" To update choose the File Server "Srv0_Nice" in zone "NOVELL", select log on method "Apple Standard UAMs", enter as Guest, go into the Folder "Applications", then the Folder "System Tools", then the Folder "Universal System", then the Folder "OT 1.1.2-NET Install" and then double click on "Open Transport Installation".
Older Macintoshes have in the Control Panel a program called MacTCP. Executing this should show a window including an icon called "Ethernet". Holding down the "Option" key while clicking on this icon should then show the ethernet address. Note that this "Option" is sometimes marked "alt" and may have a little diagram on it like
____ \__The network team at CERN needs to know the exact ethernet address for a number of reasons. Primarily, it enables them to detect if someone else tries to "borrow" and use the corresponding IP address. In addition, it may happen that they detect hardware or software problems related to the ethernet address and wish to inform the owner and/or responsible person. The information is particularly valuable for systems registered as portable and not necessarily having a fixed home network socket or IP name and address.
If you are working at CERN you should be able to check all the networking parameters of your device (and eventually inform the network team of any wrong or missing information) by using the web form:
http://network.cern.ch/register
Question - LHC++ (0098)
What are the definition for LHC++ software both at CERN and from
outside, and especially the AFS availability?
Answer -
Everything is explained in the LHC++ Web page
at URL:
http://wwwinfo.cern.ch/asd/lhc++/access.html
.
Regarding access from AFS (root directory
/afs/cern.ch/sw/lhcxx
) anyone from a cern node can have
general access. From an outside node, only the person who was
designated to be in the cern:li
group when registering
can have access to the software. And in this case, only to the
export tree: /afs/cern.ch/sw/lhcxx/export
for
exporting the software off-site. The policy is not to allow direct
use from afs for off-site. To see who is in the
cern:li
group type "pts mem cern:li"
.
Question - Java programming language
(0104)
Who can I contact at CERN for questions/problems with the Java
programming language?
Answer - There is no official support
for Java but we invite users to address their questions/problems to
the cern.java
newsgroup.
This newsgroup is intended to be the most basic communication channel for the community of Java developers at CERN. In order not to restrict the immediate evolution the scope is initially quite wide:
cern.java.*
)
in a consensual way as needs arise and different elements of the
Java infrastructure settle down. Also, no alternative communication
mechanism is discarded (creation of a Java Users group, etc..) as
long as it is convenient for the community and there is consensus
to establish it.
Question - Web access with AFS files
(0110)
I would like to restrict read access to certain web pages, and
have protected them as far as the access via the web is concerned.
The files themselves are on AFS.
How can I make them accessible to the server, but protect them from being read by other AFS users?
Answer - For the three servers
consult.cern.ch
, home.cern.ch
and
wwwinfo.cern.ch
it can be done via AFS group names in a
"generic" way.
consult
give read access to
webserver:consult
home
give read access to
webserver:home
wwwinfo
give read access to
webserver:wwwinfo
Example: If you want to restrict AFS read access to one of your home directories, just type
fs setacl
mydirname
webserver:home read