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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 Helpdesk managed by the User Support group.
N.B. The number in parenthesis refers to
its relative numbering in the User Support "Question-Answer"
database, at URL:
where NNN is the problem identifier (number).
- 'Shortcut' list in
"Start - Documents"
When I use several documents (
Excel, Word, Powerpoint,
etc.) in various orders, some of them do not appear afterwards in
the 'shortcut' list that you get via
Documents", whereas others do. In my case, all
Excel documents are not listed, whereas all other
Powerpoint ones are. Why?
Answer - You have to verify if the
setup (in your case for
Excel) is correct
Tools - Options - General:The
"Recently used file list"box must be ticked to make all previously used documents listed.
- MSDN at CERN
Do I need a licence for MSDN at CERN?
Answer - MSDN (Microsoft Developer Network) is a special program for developers organised on two levels: a free level (the on-line level) available on the Microsoft Web site, and the subscription level.
The complete MSDN package consists of CDs with all the software released by Microsoft during the year (programs, operating systems and libraries). The library part of MSDN is basically a help system containing the help and sample files for all development and back office tools such as Visual Studio, SQL, Office and IIS.
The library part can be read free from the Web site as part of the free access level. The CD of the library as well as the other CDs are not free and are not distributable even if the users have their own licences.
The MSDN library, although is not directly part of Visual Studio (i.e. VB6, VC++ 6 and the rest), is essential to the use of it, since it includes the help files. It must be installed on top of Visual Studio 6 and becomes part of it.
The current situation is that in the past we have stored VB6, VC++ 6 and the MSDN library on network servers and made them available to users through the NICE menu. For VB6 and VC++ 6 this is acceptable provided the users have their own licence, since they do not get directly the CDs. For MSDN this is illegal.
However, there are now several people using this software and relying on it. Additionally, there are negotiations under way with Microsoft to have the CERN software licence include all the development tools as of the year 2000.
For new users, the MSDN library is not available from NICE
so they have to buy it themselves - for example via the
Software Licence Office (Marlene Prigent) - or
wait until the new licence contract is in place. In any case,
VB6 and VC++ 6 users can browse the MSDN
library for free from the Microsoft site if they need
- Desktop icons
I seem to have lost all but a few of my desktop icons. Is there a way of getting them back, rather than recreating every single one again manually?
Answer - The desktop icon shortcuts
reside in the directory
J:\W95\Desktop. The quickest
solution is to have the whole directory restored from the last good
backup by an authorised person (send a mail to
email@example.com with the details).
- Passwords on AXCAD cluster
Who can change the password on the AXCAD cluster (for a Euclid user) ?
Answer - Normally this is the same as
the AFS password and it can be reset by the central Computing
Helpdesk (78888). If they cannot do it (and your login or password
remains invalid after the change) then it means that there is a
problem with your account for EUCLID. You should report the problem
EDMS.Support@cern.ch stating that your AFS
password has been changed unsuccessfully.
- Mouse usage with Exceed
I have just launched Exceed for the first time and I do not manage to get the full UNIX functionality. I have a PC with a three-button mouse, but no combination of buttons (individually or combined) are able to paste the information that I cut at other screens.
Answer - Most probably your mouse
driver is not matching your mouse type. A freshly installed
PC/NICE95 provides a
"Standard PS/2 mouse" as driver.
If yours is a Logitech (the current three-button mouse
distributed through PCD), you have to associate the appropiate
driver: open the
"System" Control Panel (menu
Start - Settings), select the
tab, double-click in
"Mouse" to see which driver is
associated to the mouse. If you have to change it double-click on
this driver, then select the
"Driver" tab and click on
"Change Driver" to select a good one (for instance
"Logitech PS/2 Port Mouse").
- Xterminals IP address
I have moved my Xterminal to another building, and in addition I wanted to change its name. I did that through the "
Web interface, and then used the standard
command to define the new IP address. However it seems that the
Xterminal still "remembers" its old IP address and then does not
boot from the server.
Answer - Xterminals have the ability to
retain some parameters (such as the IP address) in memory even when
powered off (obvioudly thanks to a battery). In order to redefine
any of those parameters you have to reset the Xterminal memory
first, via the command
NVRAM. The documentation is
quite clear regarding the steps to follow:
X Terminal Guide: section 3.4
HOST IDENTIFICATION on HPPLUS
When I logon to Frascati using
ssh from my HPPLUS
account I get error messages suggesting there is a hacking
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that the host key has just been changed. Please contact your system administrator. Add correct host key in /u1/mihai/.ssh/known_hosts to get rid of this message. Agent forwarding is disabled to avoid attacks by corrupted servers. X11 forwarding is disabled to avoid attacks by corrupted servers. Are you sure you want to continue connecting (yes/no)?What can I do to avoid this happening ?
Answer - The problem in this case is
that HPPLUS is not the name of a real node, but a dynamic alias for
a collection of 5 nodes. There is a load balancing mechanism which
initially puts you onto the least loaded node, so when addressing
"hpplus.cern.ch" you may actually reach
hpplus02, etc. This confuses
ssh which expects to find the same node at the same name
There are several ways to get around it, but none are really satisfactory:
'yes'in the knowledge that nothing "really nasty" is happening,
hpplu02.cern.chinstead of the alias. This is ok for
scp, but for
sshsessions it is not favoured by us as you would be avoiding the load balancing mechanism,
'-o "StrictHostKeyChecking=no"', or the
Note that the same error (or similar) can happen even when a
user is refering to a specific node which has been reinstalled
since the user last accessed it with
each time a machine (or node) is reinstalled, it gets a new "host
key", and the users have to delete the old one from their known
N.B. Please note that:
sshis not a 'deployed' service yet. There are several issues like this which must first be solved before this is the case.
"sysname" variable setting on LINUX
There seems to be some confusion about the "sysname" setting on LINUX and the ASIS repository: "sysname" is set to "i386_linux22" but in
/afs/cern.ch/asis/ there is only a
i386_redhat60 sub-directory. Does it mean that we should not
/afs/cern.ch/asis/@sys in the
been chosen for ASIS software, but Transarc (for AFS) has chosen
i386_linux22 for the
By experience the ASIS team knows that the
definition for AFS is not sufficient for software in ASIS. For
instance many AIX 4.2 programs do not work properly on AIX 4.3 but
"fs sysname" gives in both cases
rs_aix42. It is why (for the time being) the
@sys construct cannot be used to access ASIS
Another reason not to have
/afs/cern.ch/asis/@sys in the path is that
redhat 6.0 is not
a complete architecture in AFS. So, only a few
tools which were recompiled explicitly for
redhat 6.0 are in
/afs/cern.ch/asis/i386_redhat60. Others are in the
LD_LIBRARY_PATH on Linux
Is it necessary to set under Linux the environment variable LD_LIBRARY_PATH (as on SUN/Solaris) ?
Answer - This variable is used to
determine where to search for the shared elements for dynamic loading:
in Linux if you have NO
variable you use the contents of the file
/etc/ld.so.conf (system level default).
- Colors in
How can I make
emacs "colourful" in order to
emphasise different statements while editing code (as with
Answer - By default emacs is black and
white. An easy way to make emacs colourful is to add a single line
$HOME/.emacs file as follows:
"I'm away" message
Is there a way to influence/modify the traditional
away" subject of a vacation message? Although I do not ask
for it as part of my text it always appears in the automatic
replies to my correspondents.
Answer - Yes; instead of providing
simply the text to the
"setvacation" program, you can
Subject: your_subject_of_choice TextNote the mandatory blank line between
"Subject:"(which then becomes associated to the mail header) and the normal text.
- Search on mail folders
I have all my mail folders in AFS. How can I perform a search on the various mail folders ?
Answer - This is not yet possible with
"pine" (or only with the UNIX
command) but you can do it with
"Netscape 4.0x" (at
least on a PC): select
"Search Messages" in the
"Edit" menu, then follow the proposed selectors/buttons as
required. This works on your
INBOX as well as in
the first hierarchy of stored folders (sub-folders therein have to
be specifically open and searched for, otherwise an error
"xxx is not a selectable mailbox" appears).
The way to search through the whole Mail Server tree is to
"Mail on xxx.mailbox.cern.ch" folder (the
top of that tree). You can do the same with local mail,
- Mail Word, Excel or HTML document
How can I mail a Word, Excel or HTML document such that the recipient may read the plain text (and does not need to load Word or a Web browser)?
Answer - One possible solution, on UNIX,
is to use the
"lynx" line-mode Web browser to
process the document before sending it. You can proceed
in the following way:
lynx -dump -nolist url_to_be_translatedThe translation and formatting is not perfect (tables do not get formatted for instance) but good enough for readability.
On a PC, Word or Excel documents
can first be turned into HTML via the option
HTML" in the
"File" menu. Once done you could
do the plain-text translation using "Netscape
2(light)" (unfortunately this nice feature was dropped in
later versions): trigger the
"Mail Document" option in
"File" menu, then suppress the URL line from the
mail body; click the
"Attach" button and select
"Convert to Plain Text".
- Harrassing messages
I am getting personally e-mail-harassed by a person outside CERN; so this is not a "generic-spam" issue. What is the suggested way to proceed in order to make this known to the competent authorities and, hopefully, have legal actions following it up?
Answer - In the absence of a 'global authority' the 'standard procedure' these days is to address your complaint to the service provider who gives the 'offender' access to the Internet. In more detail, let us distinguish two scenarios. The first is an attack at your professional CERN address. In that case there is:
"hotmail.com"you might try sending your complain to
"firstname.lastname@example.org"with the complete mail headers allowing to identify the origin of those attacks.
If the attack is to your "private" address (through an external Internet provider; say you have your own hotmail account) CERN should not be involved (understandably). The technical actions still apply (transposed to your Internet provider). You might try legal actions against the offender by becoming plaintiff in front of the police or similar authorities at the offender's country of origin.
- Web Home page on
I have a problem while displaying my WWW page at
http://nicewww.cern.ch/~zamora. I have set it following the
instructions and I receive the following error:
----- HTTP Error 404 404 Not Found The Web server cannot find the file or script you asked for. Please check the URL to ensure that the path is correct. Please contact the server's administrator if this problem persists. ---However if I write explicitly:
http://nicewww.cern.ch/~zamora/default.htmthen it works fine.
Answer - It's not a bug, it's a feature. You have to use
<frame>tags in your
This is nicewww-specific:
src="contents.htm"> means that
is located in the same folder as the "parent" file. And when you
http://nicewww.cern.ch/~zamora, the Web server
thinks that the parent file is
"default.htm": it tries to retreive
http://nicewww.cern.ch/contents.htm, which is missing, of
- Access to
I want to run ROOT here at CERN. How can I access it ?
Answer - On an AFS machine like the
ATLAS_WGS set the environment variable:
$PATH. Then simply type
rootas a command line.
Alternative versions can be selected from the
/afs/cern.ch/na49/library.4/ROOT/ directory. (See
"Availability" - for more details.
"telnet" to SLAC as of September 1st 1999
When I try to "telnet" to SLAC (or use any other remote commands like
rlogin, rsh, rexec, rcp) it fails. Why ?
Answer - The answer is given in the following news published by the Network team, end of August 1999:
Please note that due to computer security reasons, SLAC will be blocking "telnet" and all remote commands (rlogin, rsh, rexec, and rcp) at their external firewall as of Wednesday, September 1st You may find additional information on this subject at: http://www2.slac.stanford.edu/security/telnet-alert.htm If this action would severely impact your work, you are requested to contact the SLAC Security Officer (email@example.com) as soon as possible. Please note that secure access using SSH is possible (try "man ssh" and the corresponding SLAC page at the URL above). You may wish to read as well about "mxconns" at: http://wwwinfo.cern.ch/dis/security/x/mxconns/ If you have further questions, please do not hesitate to contact the Computing Help Desk (x78888, Helpdesk@cern.ch), and we will do our best in trying to help you. Network Operations - IT/Communications Systems
For matters related to this article please contact the author.Cnl.Editor@cern.ch