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I use the Sun Grid Engine queuing system on one of my Rocks cluster installations.  Almost immediately following the initial installation of the system the queue began reporting errors on all of the queue nodes.  Particularly, qstat -f showed an ‘E’ for the current state of nodes 1 and 2 (a very small, test cluster).

As the owner of all the queues I was able to clear the error with the qmod command.  Using the ‘-cq all.q’ parameters after the qmod command the error message was cleared and I was able to submit jobs to the queue once more.  I didn’t think to investigate the details of the error, but its handy to know how to override such situations where the operation of the queue is impaired.

Why has it taken me the entire life span of Windows XP to even think to look for this?  This has been on O’Reilly since 2004.  This is incredibly handy when you have to work on a machine locally as administrator but the user is nowhere in sight.  Now I just have to find out how to script the part where it says to use the Task Manager to disconnect the user.  That’s annoying.
“Disable Welcome Screen& Fast User Switching via Control Panel > User Accounts. Manually edit the registry and set AllowMultipleTSSessions=dword:0000001

Now, “Disconnect” the current user using Task Manager > Users tab.

Type in the login name in the Classic Logon dialog and login as other user.

P.S: The Winkey+L cannot be used in this case to switch users. The only option is thru Taskmgr. Winkey+L still brings up the Classic Logon dialog, but terminates the current session, unlike the Task Manager method.”

mYm is a toolbox for Matlab that allows MySQL connections and calls to be made from within the application. I’ve stored a local copy of the mYm Source v1.0.9, but the author, Yannick Maret, maintains a site with the latest version.
The code will successfully compile on both Windows and Linux using the latest version of Matlab, 2006a at the time of this writing.  The following command will compile it on Linux provided you have the necessary MySQL development packages installed:

mex -I/usr/include/mysql -L/usr/lib/mysql -L/usr/lib -lz -lmysqlclient mym.cpp
However, the toolbox will fail with the following error:

>> mym(’open’,'localhost’,'username’,'password’);
??? Invalid MEX-file ‘mym.mexglx’: mym.mexglx: undefined symbol: compressBound.
This error appears related to the zlib/zlib-devel 1.2.1 package that ships with RHEL 4.3, but can be reproduced with the more recent 1.2.3 zlib installed from scratch.

Fortunately, Yannick reports that a hack to the source prior to compile will work around the zlib issue:

“That’s indeed a very strange error, and that’s the first time I’ve heard of it. I use zlib 1.2.3, and if I look at the zlib header, the function ‘compressBound’ is declared at line 1040:
ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
So, this function should be part of a working zlib distribution… If you cannot solve the error, maybe you can replace the line
const uLongf max_len = compressBound(plen[i]);
in mym.cpp by something like that
const uLongf max_len =2*(plen[i]+10);
It’s very dirty, but it should work just fine!”

And indeed it does…

There exists a little known change to the university’s Matlab license for this year and it applies to copies of Matlab running on Windows machines.  You can no longer run Matlab using either the standalone or network license via a Remote Desktop connection.  The license checks to see whether or not you are connected via Terminal Services and reports the following errors depending on the license used:

Use of the offline license file receives to receive this error:

License Manager -103.
Terminal Server remote client not allowed.

Use of the online license file receives the error:

License Manager Error -8.
Invalid (inconsistent) license key.

The Tiger Card office handles all requests to OIT for PU NetID creation and all that that entails.  This usually takes place within a 24 hour window based on what I can only assume is start or appointment date for the individual.  In my case I needed to find this out for a guest appointment, but I suspect that the accounts for faculty and graduate students are created on different schedules; I’ve seen them months in advance.