X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/bd06f9e9dc96e2a8d0dcfa2e60feaba1ddd94948..e42f5b1dad855a6ee4fe4dec43b101f4d02a5f2b:/blog/index.html diff --git a/blog/index.html b/blog/index.html index 79ea984d16..56e0d3e6d0 100644 --- a/blog/index.html +++ b/blog/index.html @@ -20,716 +20,338 @@
-
2 Spykee-roboter i hus, nå skal det lekes
-
2010-08-18 13:30
+
Oppdatert kart over overvåkningskamera i Norge
+
2010-09-22 20:50
-

Jeg kjøpte nettopp to -Spykee-roboter, for test og -leking. Kjøpte to da det var så billige, og gir meg mulighet til å -eksperimentere uten å være veldig redd for å ødelegge alt ved å bytte -ut firmware og slikt. Oppdaget at lekebutikken på Bryn senter hadde -en liten stabel på lager som de ikke hadde klart å selge ut etter -fjorårets juleinnkjøp, og var villig til å selge for en femtedel av -vanlig pris. Jeg, Ronny og Jarle har skaffet oss restbeholdningen, og -det blir morsomt å se hva vi får ut av dette.

- -

Roboten har belter styrt av to motorer, kamera, høytaler, mikrofon -og wifi-tilkobling. Det hele styrt av en GPL-lisensiert databoks som -jeg mistenker kjører linux. Firmware-kildekoden ble visst publisert i -mai. Eneste utfordringen er at kontroller-programvaren kun finnes til -Windows, men det må en kunne jobbe seg rundt når vi har kildekoden til -firmwaren. :)

- - +

For ca. et og et halvt år siden +startet +jeg på et kart over overvåkningskamera i Norge, i regi av +personvernforeningen. Det har +blitt oppdatert regelmessing, og jeg oppdaterte det nettopp. Fra den +spede start med 22 kamera registrert er det nå registrert 54 kamera. +Det er bare en brøkdel av de kamera som finnes i Norge, men det går +sakte men sikkert i riktig retning.

+ +

Informasjonen registreres fortsatt direkte inn i +OpenStreetmap, og hentes +automatisk over i + +når jeg kjører et script for å filtrere ut overvåkningskamera fra +OSM-dumpen for Norge.

- Tags: norsk, nuug. + Tags: norsk, personvern.
-
Rob Weir: How to Crush Dissent
-
2010-08-15 22:20
+
Anonym ferdsel er en menneskerett
+
2010-09-15 12:15
-

I found the notes from Rob Weir on -how -to crush dissent matching my own thoughts on the matter quite -well. Highly recommended for those wondering which road our society -should go down. In my view we have been heading the wrong way for a -long time.

+

Debatten rundt sporveiselskapet i Oslos (Ruter AS) ønske om +å +radiomerke med RFID alle sine kunder og +registerere +hvor hver og en av oss beveger oss pågår, og en ting som har +kommet lite frem i debatten er at det faktisk er en menneskerett å +kunne ferdes anonymt internt i ens eget land.

+ +

Fant en grei kilde for dette i et +skriv +fra Datatilsynet til Samferdselsdepartementet om tema:

+ +

Retten til å ferdes anonymt kan utledes av +menneskerettskonvensjonen artikkel 8 og av EUs personverndirektiv. +Her heter det at enkeltpersoners grunnleggende rettigheter og frihet +må respekteres, særlig retten til privatlivets fred. I både +personverndirektivet og i den norske personopplysningsloven er +selvråderetten til hver enkelt et av grunnprinsippene, hovedsaklig +uttrykt ved at en må gi et frivillig, informert og uttrykkelig +samtykke til behandling av personopplysninger.

+ +

For meg er det viktig at jeg kan ferdes anonymt, og det er litt av +bakgrunnen til at jeg handler med kontanter, ikke har mobiltelefon og +forventer å kunne reise med bil og kollektivtrafikk uten at det blir +registrert hvor jeg har vært. Ruter angriper min rett til å ferdes +uten radiopeiler med sin innføring av RFID-kort, og dokumenterer sitt +ønske om å registrere hvor kundene befant seg ved å ønske å gebyrlegge +oss som ikke registrerer oss hver gang vi beveger oss med +kollektivtrafikken i Oslo. Jeg synes det er hårreisende.

- Tags: english, lenker, nuug, personvern, sikkerhet. + Tags: norsk, nuug, personvern, sikkerhet.
-
No hardcoded config on Debian Edu clients
-
2010-08-09 20:15
+
Terms of use for video produced by a Canon IXUS 130 digital camera
+
2010-09-09 23:55
-

As reported earlier, the last few days I have looked at how Debian -Edu clients are configured, and tried to get rid of all hardcoded -configuration settings on the clients. I believe the work to be -mostly done, and the clients seem to work just fine with dynamically -generated configuration.

- -

What is the point, you might ask? The point is to allow a Debian -Edu desktop to integrate into an existing network infrastructure -without any manual configuration.

- -

This is what happens when installing a Debian Edu client here at -the University of Oslo using PXE. With the PXE installation, I am -asked for language (Norwegian Bokmål), locality (Norway) and keyboard -layout (no-latin1), Debian Edu profile (Roaming Workstation), if I -accept to reformat the hard drive (yes), if I want to submit info to -popcon.debian.org (no) and root password (secret). After answering -these questions, the installer goes ahead and does its thing, and -after around 50 minutes it is done. I press enter to finish the -installation, and the machine reboots into KDE. When the machine is -ready and kdm asks for login information, I enter my university -username and password, am told by kdm that a local home directory has -been created and that I must log in again, and finally log in with the -same username and password to the KDE 4.4 desktop. At no point during -this process did it ask for university specific settings, and all the -required configuration was dynamically detected using information -fetched via DHCP and DNS. The roaming workstation is now ready for -use.

- -

How was this done, you might wonder? First of all, here is the -list of things that need to be configured on the client to get it -working properly out of the box:

+

A few days ago I had the mixed pleasure of bying a new digital +camera, a Canon IXUS 130. It was instructive and very disturbing to +be able to verify that also this camera producer have the nerve to +specify how I can or can not use the videos produced with the camera. +Even thought I was aware of the issue, the options with new cameras +are limited and I ended up bying the camera anyway. What is the +problem, you might ask? It is software patents, MPEG-4, H.264 and the +MPEG-LA that is the problem, and our right to record our experiences +without asking for permissions that is at risk. + +

On page 27 of the Danish instruction manual, this section is +written:

- +
+

This product is licensed under AT&T patents for the MPEG-4 standard +and may be used for encoding MPEG-4 compliant video and/or decoding +MPEG-4 compliant video that was encoded only (1) for a personal and +non-commercial purpose or (2) by a video provider licensed under the +AT&T patents to provide MPEG-4 compliant video.

+ +

No license is granted or implied for any other use for MPEG-4 +standard.

+
-

(Hm, did I forget anything? Let me knew if I did.)

- -

The points marked (*) are not required to be able to use the -machine, but needed to provide central storage and allowing system -administrators to track their machines. Since yesterday, everything -but the sitesummary collector URL is dynamically discovered at boot -and installation time in the svn version of Debian Edu.

- -

The IP and DNS setup is fetched during boot using DHCP as usual. -When a DHCP update arrives, the proxy setup is updated by looking for -http://wpat/wpad.dat and using the content of this WPAD file to -configure the http and ftp proxy in /etc/environment and -/etc/apt/apt.conf. I decided to update the proxy setup using a DHCP -hook to ensure that the client stops using the Debian Edu proxy when -it is moved outside the Debian Edu network, and instead uses any local -proxy present on the new network when it moves around.

- -

The DNS names of the LDAP, Kerberos and syslog server and related -configuration are generated using DNS information at boot. First the -installer looks for a host named ldap in the current DNS domain. If -not found, it looks for _ldap._tcp SRV records in DNS instead. If an -LDAP server is found, its root DSE entry is requested and the -attributes namingContexts and defaultNamingContext are used to -determine which LDAP base to use for NSS. If there are several -namingContexts attibutes and the defaultNamingContext is present, that -LDAP subtree is used as the base. If defaultNamingContext is missing, -the subtrees listed as namingContexts are searched in sequence for any -object with class posixAccount or posixGroup, and the first one with -such an object is used as the LDAP base. For Kerberos, a similar -search is done by first looking for a host named kerberos, and then -for the _kerberos._tcp SRV record. I've been unable to find a way to -look up the Kerberos realm, so for this the upper case string of the -current DNS domain is used.

- -

For the syslog server, the hosts syslog and loghost are searched -for, and the _syslog._udp SRV record is consulted if no such host is -found. This algorithm works for both Debian Edu and the University of -Oslo. A similar strategy would work for locating the sitesummary -server, but have not been implemented yet. I decided to fetch and -save these settings during installation, to make sure moving to a -different network does not change the set of users being allowed to -log in nor the passwords required to log in. Usernames and passwords -will be cached by sssd when the user logs in on the Debian Edu -network, and will not change as the laptop move around. For a -non-roaming machine, there is no caching, but given that it is -supposed to stay in place it should not matter much. Perhaps we -should switch those to use sssd too?

- -

The user's SMB mount point for the network home directory is -located when the user logs in for the first time. The LDAP server is -consulted to look for the user's LDAP object and the sambaHomePath -attribute is used if found. If it isn't found, the home directory -path fetched from NSS is used instead. Assuming the path is of the -form /site/server/directory/username, the second part is looked up in -DNS and used to generate a SMB URL of the form -smb://server.domain/username. This algorithm works for both Debian -edu and the University of Oslo. Perhaps there are better attributes -to use or a better algorithm that works for more sites, but this will -do for now. :)

- -

This work should make it easier to integrate the Debian Edu clients -into any LDAP/Kerberos infrastructure, and make the current setup even -more flexible than before. I suspect it will also work for thin -client servers, allowing one to easily set up LTSP and hook it into a -existing network infrastructure, but I have not had time to test this -yet.

- -

If you want to help out with implementing these things for Debian -Edu, please contact us on debian-edu@lists.debian.org.

- -

Update 2010-08-09: Simon Farnsworth gave me a heads-up on how to -detect Kerberos realm from DNS, by looking for _kerberos TXT entries -before falling back to the upper case DNS domain name. Will have to -implement it for Debian Edu. :)

+

In short, the camera producer have chosen to use technology +(MPEG-4/H.264) that is only provided if I used it for personal and +non-commercial purposes, or ask for permission from the organisations +holding the knowledge monopoly (patent) for technology used.

+ +

This issue has been brewing for a while, and I recommend you to +read +"Why +Our Civilization's Video Art and Culture is Threatened by the +MPEG-LA" by Eugenia Loli-Queru and +"H.264 Is Not +The Sort Of Free That Matters" by Simon Phipps to learn more about +the issue. The solution is to support the +free and +open standards for video, like Ogg +Theora, and avoid MPEG-4 and H.264 if you can.

- Tags: debian edu, english, nuug. + Tags: english, fildeling, multimedia, nuug, opphavsrett, personvern, standard, video, web.
-
Testing if a file system can be used for home directories...
-
2010-08-08 21:20
+
Navteq bruker 3-12 måneder, OpenStreetmap.org trenger noen dager
+
2010-09-07 21:40
-

A few years ago, I was involved in a project planning to use -Windows file servers as home directory servers for Debian -Edu/Skolelinux machines. This was thought to be no problem, as the -access would be through the SMB network file system protocol, and we -knew other sites used SMB with unix and samba as the file server to -mount home directories without any problems. But, after months of -struggling, we had to conclude that our goal was impossible.

- -

The reason is simply that while SMB can be used for home -directories when the file server is Samba running on Unix, this only -work because of Samba have some extensions and the fact that the -underlying file system is a unix file system. When using a Windows -file server, the underlying file system do not have POSIX semantics, -and several programs will fail if the users home directory where they -want to store their configuration lack POSIX semantics.

- -

As part of this work, I wrote a small C program I want to share -with you all, to replicate a few of the problematic applications (like -OpenOffice.org and GCompris) and see if the file system was working as -it should. If you find yourself in spooky file system land, it might -help you find your way out again. This is the fs-test.c source:

- -
-/*
- * Some tests to check the file system sematics.  Used to verify that
- * CIFS from a windows server do not work properly as a linux home
- * directory.
- * License: GPL v2 or later
- * 
- * needs libsqlite3-dev and build-essential installed
- * compile with: gcc -Wall -lsqlite3 -DTEST_SQLITE fs-test.c -o fs-test
-*/
-
-#define _FILE_OFFSET_BITS 64
-#define _LARGEFILE_SOURCE 1
-#define _LARGEFILE64_SOURCE 1
-
-#define _GNU_SOURCE /* for asprintf() */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <sys/file.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#ifdef TEST_SQLITE
-/*
- * Test sqlite open, as done by gcompris require the libsqlite3-dev
- * package and linking with -lsqlite3.  A more low level test is
- * below.
- * See also <URL: http://www.sqlite.org./faq.html#q5 >.
- */
-#include <sqlite3.h>
-#define CREATE_TABLE_USERS                                              \
-  "CREATE TABLE users (user_id INT UNIQUE, login TEXT, lastname TEXT, firstname TEXT, birthdate TEXT, class_id INT ); "
-int test_sqlite_open(void) {
-  char *zErrMsg;
-  char *name = "testsqlite.db";
-  sqlite3 *db=NULL;
-  unlink(name);
-  int rc = sqlite3_open(name, &db);
-  if( rc ){
-    printf("error: sqlite open of %s failed: %s\n", name, sqlite3_errmsg(db));
-    sqlite3_close(db);
-    return -1;
-  }
-
-  /* create tables */
-  rc = sqlite3_exec(db,CREATE_TABLE_USERS, NULL,  0, &zErrMsg);
-  if( rc != SQLITE_OK ){
-    printf("error: sqlite table create failed: %s\n", zErrMsg);
-    sqlite3_close(db);
-    return -1;
-  }
-  printf("info: sqlite worked\n");
-  sqlite3_close(db);
-  return 0;
-}
-#endif /* TEST_SQLITE */
-
-/*
- * Demonstrate locking issue found in gcompris using sqlite3.  This
- * work with ext3, but not with cifs server on Windows 2003.  This is
- * done in the sqlite3 library.
- * See also
- * <URL:http://www.cygwin.com/ml/cygwin/2001-08/msg00854.html> and the
- * POSIX specification
- * <URL:http://www.opengroup.org/onlinepubs/009695399/functions/fcntl.html>.
- */
-int test_gcompris_locking(void) {
-  struct flock fl;
-  char *name = "testsqlite.db";
-  unlink(name);
-  int fd = open(name, O_RDWR|O_CREAT|O_LARGEFILE, 0644);
-  printf("info: testing fcntl locking\n");
-
-  fl.l_whence = SEEK_SET;
-  fl.l_pid    = getpid();
-  printf("  Read-locking 1 byte from 1073741824");
-  fl.l_start  = 1073741824;
-  fl.l_len    = 1;
-  fl.l_type   = F_RDLCK;
-  if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
-
-  printf("  Read-locking 510 byte from 1073741826");
-  fl.l_start  = 1073741826;
-  fl.l_len    = 510;
-  fl.l_type   = F_RDLCK;
-  if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
-
-  printf("  Unlocking 1 byte from 1073741824");
-  fl.l_start  = 1073741824;
-  fl.l_len    = 1;
-  fl.l_type   = F_UNLCK;
-  if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
-
-  printf("  Write-locking 1 byte from 1073741824");
-  fl.l_start  = 1073741824;
-  fl.l_len    = 1;
-  fl.l_type   = F_WRLCK;
-  if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
-
-  printf("  Write-locking 510 byte from 1073741826");
-  fl.l_start  = 1073741826;
-  fl.l_len    = 510;
-  if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
-
-  printf("  Unlocking 2 byte from 1073741824");
-  fl.l_start  = 1073741824;
-  fl.l_len    = 2;
-  fl.l_type   = F_UNLCK;
-  if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
-
-  close(fd);
-  return 0;
-}
-
-/*
- * Test if permissions of freshly created directories allow entries
- * below them.  This was a problem with OpenOffice.org and gcompris.
- * Mounting with option 'sync' seem to solve this problem while
- * slowing down file operations.
- */
-int test_subdirectory_creation(void) {
-#define LEVELS 5
-  char *path = strdup("test");
-  char *dirs[LEVELS];
-  int level;
-  printf("info: testing subdirectory creation\n");
-  for (level = 0; level < LEVELS; level++) {
-    char *newpath = NULL;
-    if (-1 == mkdir(path, 0777)) {
-      printf("  error: Unable to create directory '%s': %s\n",
-	     path, strerror(errno));
-      break;
-    }
-    asprintf(&newpath, "%s/%s", path, "test");
-    free(path);
-    path = newpath;
-  }
-  return 0;
-}
-
-/*
- * Test if symlinks can be created.  This was a problem detected with
- * KDE.
- */
-int test_symlinks(void) {
-  printf("info: testing symlink creation\n");
-  unlink("symlink");
-  if (-1 == symlink("file", "symlink"))
-    printf("  error: Unable to create symlink\n");
-  return 0;
-}
-
-int main(int argc, char **argv) {
-  printf("Testing POSIX/Unix sematics on file system\n");
-  test_symlinks();
-  test_subdirectory_creation();
-#ifdef TEST_SQLITE
-  test_sqlite_open();
-#endif /* TEST_SQLITE */
-  test_gcompris_locking();
-  return 0;
-}
-
- -

When everything is working, it should print something like -this:

- -
-Testing POSIX/Unix sematics on file system
-info: testing symlink creation
-info: testing subdirectory creation
-info: sqlite worked
-info: testing fcntl locking
-  Read-locking 1 byte from 1073741824
-  Read-locking 510 byte from 1073741826
-  Unlocking 1 byte from 1073741824
-  Write-locking 1 byte from 1073741824
-  Write-locking 510 byte from 1073741826
-  Unlocking 2 byte from 1073741824
-
- -

I do not remember the exact details of the problems we saw, but one -of them was with locking, where if I remember correctly, POSIX allow a -read-only lock to be upgraded to a read-write lock without unlocking -the read-only lock (while Windows do not). Another was a bug in the -CIFS/SMB client implementation in the Linux kernel where directory -meta information would be wrong for a fraction of a second, making -OpenOffice.org fail to create its deep directory tree because it was -not allowed to create files in its freshly created directory.

- -

Anyway, here is a nice tool for your tool box, might you never need -it. :)

+

Jeg ble riktig fascinert av +en +artikkel i Aftenposten om hvor hardt Navteq jobber for å oppdatere +kartene som brukes i navigasjons-GPSer, der det blant annet heter at +"på grunn av teknikken tar det alt fra tre til tolv måneder før +kartene er oppdatert". Når en kjenner hva slags oppdateringshastighet +som er tilgjengelig på +OpenStreetmap som +oppdateres på dugnad, blir det litt trist å se hva noe av det beste en +kan kjøpe for penger får til.

+ +

Fra en endrer kartdataene i databasen til OpenStreetmap tar det +ca. 15 minutter før endringen er synlig på kartet som alle kan se på +web. Dernest overføres det daglig til en kartdump som lastes ned av +personen som lager Garmin-kart for Norge ca. en gang i uken. Med +OpenStreetmap.org og Frikart.no +kan en altså ha korreksjonene på plass i sin Garmin-GPS i løpet av en +uke. Det er også av tekniske årsaker at det tar så langt tid. +Jobbene som tegner kartene, henter ut kartdumpene og konverterer til +Garmin-format tar minutter og timer å gjennomføre, slik at de ikke +gjøres kontinuerlig men kun regelmessing.

- Tags: debian edu, english, nuug. + Tags: kart, norsk, nuug.
-
Autodetecting Client setup for roaming workstations in Debian Edu
-
2010-08-07 14:45
+
Some notes on Flash in Debian and Debian Edu
+
2010-09-04 10:10
-

A few days ago, I -tried -to install a Roaming workation profile from Debian Edu/Squeeze -while on the university network here at the University of Oslo, and -noticed how much had to change to get it operational using the -university infrastructure. It was fairly easy, but it occured to me -that Debian Edu would improve a lot if I could get the client to -connect without any changes at all, and thus let the client configure -itself during installation and first boot to use the infrastructure -around it. Now I am a huge step further along that road.

- -

With our current squeeze-test packages, I can select the roaming -workstation profile and get a working laptop connecting to the -university LDAP server for user and group and our active directory -servers for Kerberos authentication. All this without any -configuration at all during installation. My users home directory got -a bookmark in the KDE menu to mount it via SMB, with the correct URL. -In short, openldap and sssd is correctly configured. In addition to -this, the client look for http://wpad/wpad.dat to configure a web -proxy, and when it fail to find it no proxy settings are stored in -/etc/environment and /etc/apt/apt.conf. Iceweasel and KDE is -configured to look for the same wpad configuration and also do not use -a proxy when at the university network. If the machine is moved to a -network with such wpad setup, it would automatically use it when DHCP -gave it a IP address.

- -

The LDAP server is located using DNS, by first looking for the DNS -entry ldap.$domain. If this do not exist, it look for the -_ldap._tcp.$domain SRV records and use the first one as the LDAP -server. Next, it connects to the LDAP server and search all -namingContexts entries for posixAccount or posixGroup objects, and -pick the first one as the LDAP base. For Kerberos, a similar -algorithm is used to locate the LDAP server, and the realm is the -uppercase version of $domain.

- -

So, what is not working, you might ask. SMB mounting my home -directory do not work. No idea why, but suspected the incorrect -Kerberos settings in /etc/krb5.conf and /etc/samba/smb.conf might be -the cause. These are not properly configured during installation, and -had to be hand-edited to get the correct Kerberos realm and server, -but SMB mounting still do not work. :(

- -

With this automatic configuration in place, I expect a Debian Edu -roaming profile installation would be able to automatically detect and -connect to any site using LDAP and Kerberos for NSS directory and PAM -authentication. It should also work out of the box in a Active -Directory environment providing posixAccount and posixGroup objects -with UID and GID values.

- -

If you want to help out with implementing these things for Debian -Edu, please contact us on debian-edu@lists.debian.org.

+

In the Debian +popularity-contest numbers, the adobe-flashplugin package the +second most popular used package that is missing in Debian. The sixth +most popular is flashplayer-mozilla. This is a clear indication that +working flash is important for Debian users. Around 10 percent of the +users submitting data to popcon.debian.org have this package +installed.

+ +

In the report written by Lars Risan in August 2008 +(«Skolelinux +i bruk – Rapport for Hurum kommune, Universitetet i Agder og +stiftelsen SLX Debian Labs»), one of the most important problems +schools experienced with Debian +Edu/Skolelinux was the lack of working Flash. A lot of educational +web sites require Flash to work, and lacking working Flash support in +the web browser and the problems with installing it was perceived as a +good reason to stay with Windows.

+ +

I once saw a funny and sad comment in a web forum, where Linux was +said to be the retarded cousin that did not really understand +everything you told him but could work fairly well. This was a +comment regarding the problems Linux have with proprietary formats and +non-standard web pages, and is sad because it exposes a fairly common +understanding of whose fault it is if web pages that only work in for +example Internet Explorer 6 fail to work on Firefox, and funny because +it explain very well how annoying it is for users when Linux +distributions do not work with the documents they receive or the web +pages they want to visit.

+ +

This is part of the reason why I believe it is important for Debian +and Debian Edu to have a well working Flash implementation in the +distribution, to get at least popular sites as Youtube and Google +Video to working out of the box. For Squeeze, Debian have the chance +to include the latest version of Gnash that will make this happen, as +the new release 0.8.8 was published a few weeks ago and is resting in +unstable. The new version work with more sites that version 0.8.7. +The Gnash maintainers have asked for a freeze exception, but the +release team have not had time to reply to it yet. I hope they agree +with me that Flash is important for the Debian desktop users, and thus +accept the new package into Squeeze.

- Tags: debian edu, english, nuug. + Tags: debian, debian edu, english, multimedia, video, web.
-
Debian Edu roaming workstation - at the university of Oslo
-
2010-08-03 23:30
+
My first perl GUI application - controlling a Spykee robot
+
2010-09-01 21:00
-

The new roaming workstation profile in Debian Edu/Squeeze is fairly -similar to the laptop setup am I working on using Ubuntu for the -University of Oslo, and just for the heck of it, I tested today how -hard it would be to integrate that profile into the university -infrastructure. In this case, it is the university LDAP server, -Active Directory Kerberos server and SMB mounting from the Netapp file -servers.

- -

I was pleasantly surprised that the only three files needed to be -changed (/etc/sssd/sssd.conf, /etc/ldap.conf and -/etc/mklocaluser.d/20-debian-edu-config) and one file had to be added -(/usr/share/perl5/Debian/Edu_Local.pm), to get the client working. -Most of the changes were to get the client to use the university LDAP -for NSS and Kerberos server for PAM, but one was to change a hard -coded DNS domain name in the mklocaluser hook from .intern to -.uio.no.

- -

This testing was so encouraging, that I went ahead and adjusted the -Debian Edu scripts and setup in subversion to centralise the roaming -workstation setup a bit more and avoid the hardcoded DNS domain name, -so that when I test this tomorrow, I expect to get away with modifying -only /etc/sssd/sssd.conf and /etc/ldap.conf to get it to use the -university servers.

- -

My goal is to get the clients to have no hardcoded settings and -fetch all their initial setup during installation and first boot, to -allow them to be inserted also into environments where the default -setup in Debian Edu has been changed or as with the university, where -the environment is different but provides the protocols Debian Edu -uses.

+

This evening I made my first Perl GUI application. The last few +days I have worked on a Perl module for controlling my recently +aquired Spykee robots, and the module is now getting complete enought +that it is possible to use it to control the robot driving at least. +It was now time to figure out how to use it to create some GUI to +allow me to drive the robot around. I picked PerlQt as I have had +positive experiences with the Qt API before, and spent a few minutes +browsing the web for examples. Using Qt Designer seemed like a short +cut, so I ended up writing the perl GUI using Qt Designer and +compiling it into a perl program using the puic program from +libqt-perl. Nothing fancy yet, but it got buttons to connect and +drive around.

+ +

The perl module I have written provide a object oriented API for +controlling the robot. Here is an small example on how to use it:

+ +

+use Spykee;
+Spykee::discover(sub {$robot{$_[0]} = $_[1]});
+my $host = (keys %robot)[0];
+my $spykee = Spykee->new();
+$spykee->contact($host, "admin", "admin");
+$spykee->left();
+sleep 2;
+$spykee->right();
+sleep 2;
+$spykee->forward();
+sleep 2;
+$spykee->back();
+sleep 2;
+$spykee->stop();
+

+ +

Thanks to the release of the source of the robot firmware, I could +peek into the implementation at the other end to figure out how to +implement the protocol used by the robot. I've implemented several of +the commands the robot understand, but is still missing the camera +support to make it possible to control the robot from remote. First I +want to implement support for uploading new firmware and configuring +the wireless network, to make it possible to bootstrap a Spykee robot +without the producers Windows and MacOSX software (I only have Linux, +so I had to ask a friend to come over to get the robot testing +going. :).

+ +

Will release the source to the public soon, but need to figure out +where to make it available first. I will add a link to +the NUUG wiki for +those that want to check back later to find it.

- Tags: debian edu, english, nuug. + Tags: english, nuug, robot.
-
Circular package dependencies harms apt recovery
-
2010-07-27 23:50
+
Forslag i stortinget om å stoppe elektronisk stemmegiving i Norge
+
2010-08-31 21:00
-

I discovered this while doing -automated -testing of upgrades from Debian Lenny to Squeeze. A few packages -in Debian still got circular dependencies, and it is often claimed -that apt and aptitude should be able to handle this just fine, but -some times these dependency loops causes apt to fail.

- -

An example is from todays -upgrade -of KDE using aptitude. In it, a bug in kdebase-workspace-data -causes perl-modules to fail to upgrade. The cause is simple. If a -package fail to unpack, then only part of packages with the circular -dependency might end up being unpacked when unpacking aborts, and the -ones already unpacked will fail to configure in the recovery phase -because its dependencies are unavailable.

- -

In this log, the problem manifest itself with this error:

- -
-dpkg: dependency problems prevent configuration of perl-modules:
- perl-modules depends on perl (>= 5.10.1-1); however:
-  Version of perl on system is 5.10.0-19lenny2.
-dpkg: error processing perl-modules (--configure):
- dependency problems - leaving unconfigured
-
- -

The perl/perl-modules circular dependency is already -reported as a bug, and will -hopefully be solved as soon as possible, but it is not the only one, -and each one of these loops in the dependency tree can cause similar -failures. Of course, they only occur when there are bugs in other -packages causing the unpacking to fail, but it is rather nasty when -the failure of one package causes the problem to become worse because -of dependency loops.

- -

Thanks to -the -tireless effort by Bill Allombert, the number of circular -dependencies -left in Debian -is dropping, and perhaps it will reach zero one day. :)

- -

Todays testing also exposed a bug in -update-notifier and -different behaviour between -apt-get and aptitude, the latter possibly caused by some circular -dependency. Reported both to BTS to try to get someone to look at -it.

+

Ble tipset i dag om at et forslag om å stoppe forsøkene med +elektronisk stemmegiving utenfor valglokaler er +til +behandling i Stortinget. +Forslaget +er fremmet av Erna Solberg, Michael Tetzschner og Trond Helleland.

+ +

Håper det får flertall.

- Tags: debian, english, nuug. + Tags: norsk, nuug, sikkerhet.
-
First Debian Edu test release (alpha0) based on Squeeze is released
-
2010-07-27 17:45
+
Broken hard link handling with sshfs
+
2010-08-30 19:30
-

I just posted this announcement culminating several months of work -with the next Debian Edu release. Not nearly done, but one major step -completed.

- -
-

This is the first test release based on Squeeze. The focus of this -release is to test the user application selection. To have a look, -install the standalone profile and let the developers know if the set -of installed packages i.e. applications should be modified. If some -user application is missing, or if there are some applications that no -longer make sense to be included in Debian Edu, please let us know. -Also, if a useful application is missing the translation for your -language of choice, please let us know too.

- -

In addition, feedback and help to polish the desktop (menus, -artwork, starters, etc.) is appreciated. We would like to ship a nice -and handy KDE4 desktop targeted for schools out of the box.

- -

The other profiles should be installable, but there is a lot more -work left to be done before they are ready, so do not expect to -much.

- -

Changes compared to the lenny based version

- -
    -
  • Everything from Debian Squeeze -
      -
    • Desktop environment KDE 4.4 => the new KDE desktop in - combination with some new artwork -
    • Web browser Iceweasel 3.5 -
    • OpenOffice.org 3.2 -
    • Educational toolbox GCompris 9.3 -
    • Music creator Rosegarden 10.04.2 -
    • Image editor Gimp 2.6.10 -
    • Virtual universe Celestia 1.6.0 -
    • Virtual stargazer Stellarium 0.10.4 -
    • 3D modeler Blender 2.49.2 (new application) -
    • Video editor Kdenlive 0.7.7 (new application) -
    • -
  • Now using Kerberos for password checking (migration not finished). - Enabled for: -
      -
    • PAM -
    • LDAP -
    • IMAP -
    • SMTP (sender verification) -
    -
    • -
  • New experimental roaming workstation profile for laptops.
    • -
  • Show welcome page to users when they first log in. The URL is - fetched from LDAP.
    • -
  • New LXDE desktop option, in addition to KDE (default) and Gnome.
    • -
  • General cleanup (not finished)
    • -
-

The following features are not working as they should

- -
    -
  • No web based administration tool for creating users and groups. The - scripts ldap-createuser-krb and ldap-add-user-to-group can be used - for testing.
    • -
  • DVD installs are missing debian-installer images for the PXE boot, - and do not set up the PXE menu on eth0 because of this. LTSP - clients should still boot from eth1 on thin client servers.
    • -
  • The restructured KDE menu is not implemented.
    • -
  • The LDAP server setup need to be reviewed for security.
    • -
  • The LDAP directory structure need to be reworked.
    • -
  • Different sets of packages are installed when using the DVD and the - netinst CD. More packages are installed using the netinst CD.
    • -
  • The jackd package fail to install. This is believed to be caused by - some ongoing transition, and hopefully should be solved soon. The - jackd1 package can be installed manually for those that need it.
    • -
  • Some packages lack translations. See - http://wiki.debian.org/DebianEdu/Status/Squeeze for updated status, - and help out with translations.
    • -
- -

To download this multiarch netinstall release you can use

- - -

To download this multiarch dvd release you can use

- - - -

There is no source DVD available yet. It will be prepared when we -get closer to the final release.

- -

The MD5SUM of these images are

+

Just got an email from Tobias Gruetzmacher as a followup on my +previous +post about sshfs. He reported another problem with sshfs. It +fail to handle hard links properly. A simple way to spot this is to +look at the . and .. entries in the directory tree. These should have +a link count >1, but on sshfs the count is 1. I just tested to see +what happen when trying to hardlink, and this fail as well:

-
    -
  • 3dbf45d59f42a53518b6e3c9ec3b5eb6 debian-edu-6.0.0+edua0-CD.iso
    • -
  • 22f2cbfce281d1c6e478be452638675d debian-edu-6.0.0+edua0-DVD.iso
    • -
+
+% ln foo bar
+ln: creating hard link `bar' => `foo': Function not implemented
+%
+
-

The SHA1SUM of these images are

-
    -
  • c53d1b69b40cf37cd27aefaf33f6f6a3821bedf0 debian-edu-6.0.0+edua0-CD.iso
    • -
  • 2ec29d7db676d59d32197b05c277ffe16348376c debian-edu-6.0.0+edua0-DVD.iso
    • -
-

How to report bugs: -http://wiki.debian.org/DebianEdu/HowTo/ReportBugsInBugzilla

+

I have not yet found time to implement a test for this in my file +system test code, but believe having working hard links is useful to +avoid surprised unix programs. Not as useful as working file locking +and symlinks, which are required to get a working desktop, but useful +nevertheless. :)

-

Please direct replies to debian-edu@lists.debian.org

-
+

The latest version of the file system test code is available via +git from +http://github.com/gebi/fs-test

@@ -742,88 +364,78 @@ http://wiki.debian.org/DebianEdu/HowTo/ReportBugsInBugzilla

-
One step closer to single signon in Debian Edu
-
2010-07-25 10:00
+
Sikkerhetsteateret på flyplassene fortsetter
+
2010-08-28 10:40
-

The last few months me and the other Debian Edu developers have -been working hard to get the Debian/Squeeze based version of Debian -Edu/Skolelinux into shape. This future version will use Kerberos for -authentication, and services are slowly migrated to single signon, -getting rid of password questions one at the time.

- -

It will also feature a roaming workstation profile with local home -directory, for laptops that are only some times on the Skolelinux -network, and for this profile a shortcut is created in Gnome and KDE -to gain access to the users home directory on the file server. This -shortcut uses SMB at the moment, and yesterday I had time to test if -SMB mounting had started working in KDE after we added the cifs-utils -package. I was pleasantly surprised how well it worked.

- -

Thanks to the recent changes to our samba configuration to get it -to use Kerberos for authentication, there were no question about user -password when mounting the SMB volume. A simple click on the shortcut -in the KDE menu, and a window with the home directory popped -up. :)

- -

One step closer to a single signon solution out of the box in -Debian Edu. We already had PAM, LDAP, IMAP and SMTP in place, and now -also Samba. Next step is Cups and hopefully also NFS.

- -

We had planned a alpha0 release of Debian Edu for today, but thanks -to the autobuilder administrators for some architectures being slow to -sign packages, we are still missing the fixed LTSP package we need for -the release. It was uploaded three days ago with urgency=high, and if -it had entered testing yesterday we would have been able to test it in -time for a alpha0 release today. As the binaries for ia64 and powerpc -still not uploaded to the Debian archive, we need to delay the alpha -release another day.

- -

If you want to help out with implementing Kerberos for Debian Edu, -please contact us on debian-edu@lists.debian.org.

+

Jeg skrev for et halvt år siden hvordan +samfunnet +kaster bort ressurser på sikkerhetstiltak som ikke fungerer. Kom +nettopp over en +historie +fra en pilot fra USA som kommenterer det samme. Jeg mistenker det +kun er uvitenhet og autoritetstro som gjør at så få protesterer. Har +veldig sans for piloten omtalt i Aftenposten 2007-10-23, +og skulle ønske flere rettet oppmerksomhet mot problemet. Det gir +ikke meg trygghetsfølelse på flyplassene når jeg ser at +flyplassadministrasjonen kaster bort folk, penger og tid på tull i +stedet for ting som bidrar til reell økning av sikkerheten. Det +forteller meg jo at vurderingsevnen til de som burde bidra til økt +sikkerhet er svært sviktende, noe som ikke taler godt for de andre +tiltakene.

+ +

Mon tro hva som skjer hvis det fantes en enkel brosjyre å skrive ut +fra Internet som forklarte hva som er galt med sikkerhetsopplegget på +flyplassene, og folk skrev ut og la en bunke på flyplassene når de +passerte. Kanskje det ville fått flere til å få øynene opp for +problemet.

+ +

Personlig synes jeg flyopplevelsen er blitt så avskyelig at jeg +forsøker å klare meg med tog, bil og båt for å slippe ubehaget. Det +er dog noe vanskelig i det langstrakte Norge og for å kunne besøke de +delene av verden jeg ønsker å nå. Mistenker at flere har det slik, og +at dette går ut over inntjeningen til flyselskapene. Det er antagelig +en god ting sett fra et miljøperspektiv, men det er en annen sak.

- Tags: debian edu, english, nuug, sikkerhet. + Tags: norsk, nuug, personvern, sikkerhet.
-
Digitale restriksjonsmekanismer fikk meg til å slutte å kjøpe musikk
-
2010-07-22 23:50
+
Skolelinux i Osloskolen
+
2010-08-26 22:25
-

For mange år siden slutte jeg å kjøpe musikk-CDer. Årsaken var at -musikkbransjen var godt i gang med å selge platene sine med DRM som -gjorde at jeg ikke fikk spilt av musikken jeg kjøpte på utstyret jeg -hadde tilgjengelig, dvs. min datamaskin. Det var umulig å se på en -plate om den var ødelagt eller ikke, og jeg hadde jo allerede en -anseelig samling med plater, så jeg bestemme meg for å slutte å gi -penger til en bransje som åpenbart ikke respekterte meg.

- -

Jeg har mange titalls dager med musikk på CD i dag. Det meste er -lagt i et stort arkiv som kan spilles av fra husets datamaskiner (har -ikke rukket rippe alt). Jeg ser dermed ikke behovet for å skaffe mer -musikk. De fleste av mine favoritter er i hus, og jeg er dermed godt -fornøyd.

- -

Hvis musikkbransjen ønsker mine penger, så må de demonstrere at de -setter pris på meg som kunde, og ikke skremme meg bort med DRM og -antydninger om at kundene er kriminelle.

- -

Filmbransjen er like ille, men mens musikk gjerne varer lenge, er -filmer mer ferskvare. Har dermed ikke helt sluttet å kjøpe filmer, men -holder meg til DVD-filmer som kan spilles av på mine Linuxbokser. -Kommer neppe til å ta i bruk Blueray, og ei heller de nye DRM-greiene -«Ultraviolet» som be annonsert her om dagen.

+

Denne høsten skal endelig alle Osloskolene få mulighet til å bruke +Skolelinux. Ny IT-løsning +har vært rullet ut i noen måneder nå, og så vidt jeg fikk vite før +sommeren skulle alle skoler ha nytt opplegg på plass før oppstart nå i +høst. På alle skolene skal en kunne velge ved installasjon om en skal +ha Windows eller Skolelinux på maskinene, og en kan i tillegg +PXE-boote maskinene over nett som tynne klienter eller diskløse +arbeidsstasjoner. Jeg er spent på hvor mange skoler som velger å ta i +bruk Skolelinux, og gleder meg til å se hvordan dette utvikler seg. +Løsningen leveres av +Logica med +Skolelinux Drift AS som +underleverandør, og jeg har vært involvert i utviklingen av løsningen +via Skolelinux Drift AS siden prosjektet starter. Jeg synes det er +fantastisk at Skolelinux er kommet så langt siden vi startet i 2001 at +alle elevene i Osloskolene nå skal få mulighet til å bruke +løsningen. Jeg håper de vil sette pris på alle de +fantastiske +brukerprogrammene som er tilgjengelig i Skolelinux.

- Tags: fildeling, norsk, nuug, opphavsrett, personvern. + Tags: debian edu, norsk.
@@ -857,7 +469,9 @@ Kommer neppe til å ta i bruk Blueray, og ei heller de nye DRM-greiene
  • July (12)
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  • August (13)
    • + +
  • September (6)
    • @@ -914,17 +528,17 @@ Kommer neppe til Ã¥ ta i bruk Blueray, og ei heller de nye DRM-greiene
  • bootsystem (10)
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  • ldap (8)
    • @@ -932,33 +546,35 @@ Kommer neppe til Ã¥ ta i bruk Blueray, og ei heller de nye DRM-greiene
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