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1 <?xml version="1.0" encoding="utf-8"?>
2 <rss version='2.0' xmlns:lj='http://www.livejournal.org/rss/lj/1.0/' xmlns:atom="http://www.w3.org/2005/Atom">
3 <channel>
4 <title>Petter Reinholdtsen</title>
5 <description></description>
6 <link>http://people.skolelinux.org/pere/blog/</link>
7 <atom:link href="http://people.skolelinux.org/pere/blog/index.rss" rel="self" type="application/rss+xml" />
8
9 <item>
10 <title>Rob Weir: How to Crush Dissent</title>
11 <link>http://people.skolelinux.org/pere/blog/Rob_Weir__How_to_Crush_Dissent.html</link>
12 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Rob_Weir__How_to_Crush_Dissent.html</guid>
13 <pubDate>Sun, 15 Aug 2010 22:20:00 +0200</pubDate>
14 <description>
15 &lt;p&gt;I found the notes from Rob Weir on
16 &lt;a href=&quot;http://feedproxy.google.com/~r/robweir/antic-atom/~3/VGb23-kta8c/how-to-crush-dissent.html&quot;&gt;how
17 to crush dissent&lt;/a&gt; matching my own thoughts on the matter quite
18 well. Highly recommended for those wondering which road our society
19 should go down. In my view we have been heading the wrong way for a
20 long time.&lt;/p&gt;
21 </description>
22 </item>
23
24 <item>
25 <title>No hardcoded config on Debian Edu clients</title>
26 <link>http://people.skolelinux.org/pere/blog/No_hardcoded_config_on_Debian_Edu_clients.html</link>
27 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/No_hardcoded_config_on_Debian_Edu_clients.html</guid>
28 <pubDate>Mon, 9 Aug 2010 20:15:00 +0200</pubDate>
29 <description>
30 &lt;p&gt;As reported earlier, the last few days I have looked at how Debian
31 Edu clients are configured, and tried to get rid of all hardcoded
32 configuration settings on the clients. I believe the work to be
33 mostly done, and the clients seem to work just fine with dynamically
34 generated configuration.&lt;/p&gt;
35
36 &lt;p&gt;What is the point, you might ask? The point is to allow a Debian
37 Edu desktop to integrate into an existing network infrastructure
38 without any manual configuration.&lt;/p&gt;
39
40 &lt;p&gt;This is what happens when installing a Debian Edu client here at
41 the University of Oslo using PXE. With the PXE installation, I am
42 asked for language (Norwegian Bokmål), locality (Norway) and keyboard
43 layout (no-latin1), Debian Edu profile (Roaming Workstation), if I
44 accept to reformat the hard drive (yes), if I want to submit info to
45 popcon.debian.org (no) and root password (secret). After answering
46 these questions, the installer goes ahead and does its thing, and
47 after around 50 minutes it is done. I press enter to finish the
48 installation, and the machine reboots into KDE. When the machine is
49 ready and kdm asks for login information, I enter my university
50 username and password, am told by kdm that a local home directory has
51 been created and that I must log in again, and finally log in with the
52 same username and password to the KDE 4.4 desktop. At no point during
53 this process did it ask for university specific settings, and all the
54 required configuration was dynamically detected using information
55 fetched via DHCP and DNS. The roaming workstation is now ready for
56 use.&lt;/p&gt;
57
58 &lt;p&gt;How was this done, you might wonder? First of all, here is the
59 list of things that need to be configured on the client to get it
60 working properly out of the box:&lt;/p&gt;
61
62 &lt;ul&gt;
63 &lt;li&gt;IP address/netmask and DNS server.&lt;/li&gt;
64 &lt;li&gt;Web proxy URL.&lt;/li&gt;
65 &lt;li&gt;LDAP server for NSS directory information (user, group, etc).&lt;/li&gt;
66 &lt;li&gt;Kerberos server for PAM password checking.&lt;/li&gt;
67 &lt;li&gt;SMB mount point to access the network home directory. (*)&lt;/li&gt;
68 &lt;li&gt;Central syslog server to send syslog messages to. (*)&lt;/li&gt;
69 &lt;li&gt;Sitesummary collector URL to submit info to central server. (*)&lt;/li&gt;
70 &lt;/ul&gt;
71
72 &lt;p&gt;(Hm, did I forget anything? Let me knew if I did.)&lt;/p&gt;
73
74 &lt;p&gt;The points marked (*) are not required to be able to use the
75 machine, but needed to provide central storage and allowing system
76 administrators to track their machines. Since yesterday, everything
77 but the sitesummary collector URL is dynamically discovered at boot
78 and installation time in the svn version of Debian Edu.&lt;/p&gt;
79
80 &lt;p&gt;The IP and DNS setup is fetched during boot using DHCP as usual.
81 When a DHCP update arrives, the proxy setup is updated by looking for
82 http://wpat/wpad.dat and using the content of this WPAD file to
83 configure the http and ftp proxy in /etc/environment and
84 /etc/apt/apt.conf. I decided to update the proxy setup using a DHCP
85 hook to ensure that the client stops using the Debian Edu proxy when
86 it is moved outside the Debian Edu network, and instead uses any local
87 proxy present on the new network when it moves around.&lt;/p&gt;
88
89 &lt;p&gt;The DNS names of the LDAP, Kerberos and syslog server and related
90 configuration are generated using DNS information at boot. First the
91 installer looks for a host named ldap in the current DNS domain. If
92 not found, it looks for _ldap._tcp SRV records in DNS instead. If an
93 LDAP server is found, its root DSE entry is requested and the
94 attributes namingContexts and defaultNamingContext are used to
95 determine which LDAP base to use for NSS. If there are several
96 namingContexts attibutes and the defaultNamingContext is present, that
97 LDAP subtree is used as the base. If defaultNamingContext is missing,
98 the subtrees listed as namingContexts are searched in sequence for any
99 object with class posixAccount or posixGroup, and the first one with
100 such an object is used as the LDAP base. For Kerberos, a similar
101 search is done by first looking for a host named kerberos, and then
102 for the _kerberos._tcp SRV record. I&#39;ve been unable to find a way to
103 look up the Kerberos realm, so for this the upper case string of the
104 current DNS domain is used.&lt;/p&gt;
105
106 &lt;p&gt;For the syslog server, the hosts syslog and loghost are searched
107 for, and the _syslog._udp SRV record is consulted if no such host is
108 found. This algorithm works for both Debian Edu and the University of
109 Oslo. A similar strategy would work for locating the sitesummary
110 server, but have not been implemented yet. I decided to fetch and
111 save these settings during installation, to make sure moving to a
112 different network does not change the set of users being allowed to
113 log in nor the passwords required to log in. Usernames and passwords
114 will be cached by sssd when the user logs in on the Debian Edu
115 network, and will not change as the laptop move around. For a
116 non-roaming machine, there is no caching, but given that it is
117 supposed to stay in place it should not matter much. Perhaps we
118 should switch those to use sssd too?&lt;/p&gt;
119
120 &lt;p&gt;The user&#39;s SMB mount point for the network home directory is
121 located when the user logs in for the first time. The LDAP server is
122 consulted to look for the user&#39;s LDAP object and the sambaHomePath
123 attribute is used if found. If it isn&#39;t found, the home directory
124 path fetched from NSS is used instead. Assuming the path is of the
125 form /site/server/directory/username, the second part is looked up in
126 DNS and used to generate a SMB URL of the form
127 smb://server.domain/username. This algorithm works for both Debian
128 edu and the University of Oslo. Perhaps there are better attributes
129 to use or a better algorithm that works for more sites, but this will
130 do for now. :)&lt;/p&gt;
131
132 &lt;p&gt;This work should make it easier to integrate the Debian Edu clients
133 into any LDAP/Kerberos infrastructure, and make the current setup even
134 more flexible than before. I suspect it will also work for thin
135 client servers, allowing one to easily set up LTSP and hook it into a
136 existing network infrastructure, but I have not had time to test this
137 yet.&lt;/p&gt;
138
139 &lt;p&gt;If you want to help out with implementing these things for Debian
140 Edu, please contact us on debian-edu@lists.debian.org.&lt;/p&gt;
141
142 &lt;p&gt;Update 2010-08-09: Simon Farnsworth gave me a heads-up on how to
143 detect Kerberos realm from DNS, by looking for _kerberos TXT entries
144 before falling back to the upper case DNS domain name. Will have to
145 implement it for Debian Edu. :)&lt;/p&gt;
146 </description>
147 </item>
148
149 <item>
150 <title>Testing if a file system can be used for home directories...</title>
151 <link>http://people.skolelinux.org/pere/blog/Testing_if_a_file_system_can_be_used_for_home_directories___.html</link>
152 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Testing_if_a_file_system_can_be_used_for_home_directories___.html</guid>
153 <pubDate>Sun, 8 Aug 2010 21:20:00 +0200</pubDate>
154 <description>
155 &lt;p&gt;A few years ago, I was involved in a project planning to use
156 Windows file servers as home directory servers for Debian
157 Edu/Skolelinux machines. This was thought to be no problem, as the
158 access would be through the SMB network file system protocol, and we
159 knew other sites used SMB with unix and samba as the file server to
160 mount home directories without any problems. But, after months of
161 struggling, we had to conclude that our goal was impossible.&lt;/p&gt;
162
163 &lt;p&gt;The reason is simply that while SMB can be used for home
164 directories when the file server is Samba running on Unix, this only
165 work because of Samba have some extensions and the fact that the
166 underlying file system is a unix file system. When using a Windows
167 file server, the underlying file system do not have POSIX semantics,
168 and several programs will fail if the users home directory where they
169 want to store their configuration lack POSIX semantics.&lt;/p&gt;
170
171 &lt;p&gt;As part of this work, I wrote a small C program I want to share
172 with you all, to replicate a few of the problematic applications (like
173 OpenOffice.org and GCompris) and see if the file system was working as
174 it should. If you find yourself in spooky file system land, it might
175 help you find your way out again. This is the fs-test.c source:&lt;/p&gt;
176
177 &lt;pre&gt;
178 /*
179 * Some tests to check the file system sematics. Used to verify that
180 * CIFS from a windows server do not work properly as a linux home
181 * directory.
182 * License: GPL v2 or later
183 *
184 * needs libsqlite3-dev and build-essential installed
185 * compile with: gcc -Wall -lsqlite3 -DTEST_SQLITE fs-test.c -o fs-test
186 */
187
188 #define _FILE_OFFSET_BITS 64
189 #define _LARGEFILE_SOURCE 1
190 #define _LARGEFILE64_SOURCE 1
191
192 #define _GNU_SOURCE /* for asprintf() */
193
194 #include &amp;lt;errno.h&gt;
195 #include &amp;lt;fcntl.h&gt;
196 #include &amp;lt;stdio.h&gt;
197 #include &amp;lt;string.h&gt;
198 #include &amp;lt;stdlib.h&gt;
199 #include &amp;lt;sys/file.h&gt;
200 #include &amp;lt;sys/stat.h&gt;
201 #include &amp;lt;sys/types.h&gt;
202 #include &amp;lt;unistd.h&gt;
203
204 #ifdef TEST_SQLITE
205 /*
206 * Test sqlite open, as done by gcompris require the libsqlite3-dev
207 * package and linking with -lsqlite3. A more low level test is
208 * below.
209 * See also &amp;lt;URL: http://www.sqlite.org./faq.html#q5 &gt;.
210 */
211 #include &amp;lt;sqlite3.h&gt;
212 #define CREATE_TABLE_USERS \
213 &quot;CREATE TABLE users (user_id INT UNIQUE, login TEXT, lastname TEXT, firstname TEXT, birthdate TEXT, class_id INT ); &quot;
214 int test_sqlite_open(void) {
215 char *zErrMsg;
216 char *name = &quot;testsqlite.db&quot;;
217 sqlite3 *db=NULL;
218 unlink(name);
219 int rc = sqlite3_open(name, &amp;db);
220 if( rc ){
221 printf(&quot;error: sqlite open of %s failed: %s\n&quot;, name, sqlite3_errmsg(db));
222 sqlite3_close(db);
223 return -1;
224 }
225
226 /* create tables */
227 rc = sqlite3_exec(db,CREATE_TABLE_USERS, NULL, 0, &amp;zErrMsg);
228 if( rc != SQLITE_OK ){
229 printf(&quot;error: sqlite table create failed: %s\n&quot;, zErrMsg);
230 sqlite3_close(db);
231 return -1;
232 }
233 printf(&quot;info: sqlite worked\n&quot;);
234 sqlite3_close(db);
235 return 0;
236 }
237 #endif /* TEST_SQLITE */
238
239 /*
240 * Demonstrate locking issue found in gcompris using sqlite3. This
241 * work with ext3, but not with cifs server on Windows 2003. This is
242 * done in the sqlite3 library.
243 * See also
244 * &amp;lt;URL:http://www.cygwin.com/ml/cygwin/2001-08/msg00854.html&gt; and the
245 * POSIX specification
246 * &amp;lt;URL:http://www.opengroup.org/onlinepubs/009695399/functions/fcntl.html&gt;.
247 */
248 int test_gcompris_locking(void) {
249 struct flock fl;
250 char *name = &quot;testsqlite.db&quot;;
251 unlink(name);
252 int fd = open(name, O_RDWR|O_CREAT|O_LARGEFILE, 0644);
253 printf(&quot;info: testing fcntl locking\n&quot;);
254
255 fl.l_whence = SEEK_SET;
256 fl.l_pid = getpid();
257 printf(&quot; Read-locking 1 byte from 1073741824&quot;);
258 fl.l_start = 1073741824;
259 fl.l_len = 1;
260 fl.l_type = F_RDLCK;
261 if (0 != fcntl(fd, F_SETLK, &amp;fl) ) printf(&quot; - error!\n&quot;); else printf(&quot;\n&quot;);
262
263 printf(&quot; Read-locking 510 byte from 1073741826&quot;);
264 fl.l_start = 1073741826;
265 fl.l_len = 510;
266 fl.l_type = F_RDLCK;
267 if (0 != fcntl(fd, F_SETLK, &amp;fl) ) printf(&quot; - error!\n&quot;); else printf(&quot;\n&quot;);
268
269 printf(&quot; Unlocking 1 byte from 1073741824&quot;);
270 fl.l_start = 1073741824;
271 fl.l_len = 1;
272 fl.l_type = F_UNLCK;
273 if (0 != fcntl(fd, F_SETLK, &amp;fl) ) printf(&quot; - error!\n&quot;); else printf(&quot;\n&quot;);
274
275 printf(&quot; Write-locking 1 byte from 1073741824&quot;);
276 fl.l_start = 1073741824;
277 fl.l_len = 1;
278 fl.l_type = F_WRLCK;
279 if (0 != fcntl(fd, F_SETLK, &amp;fl) ) printf(&quot; - error!\n&quot;); else printf(&quot;\n&quot;);
280
281 printf(&quot; Write-locking 510 byte from 1073741826&quot;);
282 fl.l_start = 1073741826;
283 fl.l_len = 510;
284 if (0 != fcntl(fd, F_SETLK, &amp;fl) ) printf(&quot; - error!\n&quot;); else printf(&quot;\n&quot;);
285
286 printf(&quot; Unlocking 2 byte from 1073741824&quot;);
287 fl.l_start = 1073741824;
288 fl.l_len = 2;
289 fl.l_type = F_UNLCK;
290 if (0 != fcntl(fd, F_SETLK, &amp;fl) ) printf(&quot; - error!\n&quot;); else printf(&quot;\n&quot;);
291
292 close(fd);
293 return 0;
294 }
295
296 /*
297 * Test if permissions of freshly created directories allow entries
298 * below them. This was a problem with OpenOffice.org and gcompris.
299 * Mounting with option &#39;sync&#39; seem to solve this problem while
300 * slowing down file operations.
301 */
302 int test_subdirectory_creation(void) {
303 #define LEVELS 5
304 char *path = strdup(&quot;test&quot;);
305 char *dirs[LEVELS];
306 int level;
307 printf(&quot;info: testing subdirectory creation\n&quot;);
308 for (level = 0; level &amp;lt; LEVELS; level++) {
309 char *newpath = NULL;
310 if (-1 == mkdir(path, 0777)) {
311 printf(&quot; error: Unable to create directory &#39;%s&#39;: %s\n&quot;,
312 path, strerror(errno));
313 break;
314 }
315 asprintf(&amp;newpath, &quot;%s/%s&quot;, path, &quot;test&quot;);
316 free(path);
317 path = newpath;
318 }
319 return 0;
320 }
321
322 /*
323 * Test if symlinks can be created. This was a problem detected with
324 * KDE.
325 */
326 int test_symlinks(void) {
327 printf(&quot;info: testing symlink creation\n&quot;);
328 unlink(&quot;symlink&quot;);
329 if (-1 == symlink(&quot;file&quot;, &quot;symlink&quot;))
330 printf(&quot; error: Unable to create symlink\n&quot;);
331 return 0;
332 }
333
334 int main(int argc, char **argv) {
335 printf(&quot;Testing POSIX/Unix sematics on file system\n&quot;);
336 test_symlinks();
337 test_subdirectory_creation();
338 #ifdef TEST_SQLITE
339 test_sqlite_open();
340 #endif /* TEST_SQLITE */
341 test_gcompris_locking();
342 return 0;
343 }
344 &lt;/pre&gt;
345
346 &lt;p&gt;When everything is working, it should print something like
347 this:&lt;/p&gt;
348
349 &lt;pre&gt;
350 Testing POSIX/Unix sematics on file system
351 info: testing symlink creation
352 info: testing subdirectory creation
353 info: sqlite worked
354 info: testing fcntl locking
355 Read-locking 1 byte from 1073741824
356 Read-locking 510 byte from 1073741826
357 Unlocking 1 byte from 1073741824
358 Write-locking 1 byte from 1073741824
359 Write-locking 510 byte from 1073741826
360 Unlocking 2 byte from 1073741824
361 &lt;/pre&gt;
362
363 &lt;p&gt;I do not remember the exact details of the problems we saw, but one
364 of them was with locking, where if I remember correctly, POSIX allow a
365 read-only lock to be upgraded to a read-write lock without unlocking
366 the read-only lock (while Windows do not). Another was a bug in the
367 CIFS/SMB client implementation in the Linux kernel where directory
368 meta information would be wrong for a fraction of a second, making
369 OpenOffice.org fail to create its deep directory tree because it was
370 not allowed to create files in its freshly created directory.&lt;/p&gt;
371
372 &lt;p&gt;Anyway, here is a nice tool for your tool box, might you never need
373 it. :)&lt;/p&gt;
374 </description>
375 </item>
376
377 <item>
378 <title>Autodetecting Client setup for roaming workstations in Debian Edu</title>
379 <link>http://people.skolelinux.org/pere/blog/Autodetecting_Client_setup_for_roaming_workstations_in_Debian_Edu.html</link>
380 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Autodetecting_Client_setup_for_roaming_workstations_in_Debian_Edu.html</guid>
381 <pubDate>Sat, 7 Aug 2010 14:45:00 +0200</pubDate>
382 <description>
383 &lt;p&gt;A few days ago, I
384 &lt;a href=&quot;http://people.skolelinux.org/pere/blog/Debian_Edu_roaming_workstation___at_the_university_of_Oslo.html&quot;&gt;tried
385 to install&lt;/a&gt; a Roaming workation profile from Debian Edu/Squeeze
386 while on the university network here at the University of Oslo, and
387 noticed how much had to change to get it operational using the
388 university infrastructure. It was fairly easy, but it occured to me
389 that Debian Edu would improve a lot if I could get the client to
390 connect without any changes at all, and thus let the client configure
391 itself during installation and first boot to use the infrastructure
392 around it. Now I am a huge step further along that road.&lt;/p&gt;
393
394 &lt;p&gt;With our current squeeze-test packages, I can select the roaming
395 workstation profile and get a working laptop connecting to the
396 university LDAP server for user and group and our active directory
397 servers for Kerberos authentication. All this without any
398 configuration at all during installation. My users home directory got
399 a bookmark in the KDE menu to mount it via SMB, with the correct URL.
400 In short, openldap and sssd is correctly configured. In addition to
401 this, the client look for http://wpad/wpad.dat to configure a web
402 proxy, and when it fail to find it no proxy settings are stored in
403 /etc/environment and /etc/apt/apt.conf. Iceweasel and KDE is
404 configured to look for the same wpad configuration and also do not use
405 a proxy when at the university network. If the machine is moved to a
406 network with such wpad setup, it would automatically use it when DHCP
407 gave it a IP address.&lt;/p&gt;
408
409 &lt;p&gt;The LDAP server is located using DNS, by first looking for the DNS
410 entry ldap.$domain. If this do not exist, it look for the
411 _ldap._tcp.$domain SRV records and use the first one as the LDAP
412 server. Next, it connects to the LDAP server and search all
413 namingContexts entries for posixAccount or posixGroup objects, and
414 pick the first one as the LDAP base. For Kerberos, a similar
415 algorithm is used to locate the LDAP server, and the realm is the
416 uppercase version of $domain.&lt;/p&gt;
417
418 &lt;p&gt;So, what is not working, you might ask. SMB mounting my home
419 directory do not work. No idea why, but suspected the incorrect
420 Kerberos settings in /etc/krb5.conf and /etc/samba/smb.conf might be
421 the cause. These are not properly configured during installation, and
422 had to be hand-edited to get the correct Kerberos realm and server,
423 but SMB mounting still do not work. :(&lt;/p&gt;
424
425 &lt;p&gt;With this automatic configuration in place, I expect a Debian Edu
426 roaming profile installation would be able to automatically detect and
427 connect to any site using LDAP and Kerberos for NSS directory and PAM
428 authentication. It should also work out of the box in a Active
429 Directory environment providing posixAccount and posixGroup objects
430 with UID and GID values.&lt;/p&gt;
431
432 &lt;p&gt;If you want to help out with implementing these things for Debian
433 Edu, please contact us on debian-edu@lists.debian.org.&lt;/p&gt;
434 </description>
435 </item>
436
437 <item>
438 <title>Debian Edu roaming workstation - at the university of Oslo</title>
439 <link>http://people.skolelinux.org/pere/blog/Debian_Edu_roaming_workstation___at_the_university_of_Oslo.html</link>
440 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Debian_Edu_roaming_workstation___at_the_university_of_Oslo.html</guid>
441 <pubDate>Tue, 3 Aug 2010 23:30:00 +0200</pubDate>
442 <description>
443 &lt;p&gt;The new roaming workstation profile in Debian Edu/Squeeze is fairly
444 similar to the laptop setup am I working on using Ubuntu for the
445 University of Oslo, and just for the heck of it, I tested today how
446 hard it would be to integrate that profile into the university
447 infrastructure. In this case, it is the university LDAP server,
448 Active Directory Kerberos server and SMB mounting from the Netapp file
449 servers.&lt;/p&gt;
450
451 &lt;p&gt;I was pleasantly surprised that the only three files needed to be
452 changed (/etc/sssd/sssd.conf, /etc/ldap.conf and
453 /etc/mklocaluser.d/20-debian-edu-config) and one file had to be added
454 (/usr/share/perl5/Debian/Edu_Local.pm), to get the client working.
455 Most of the changes were to get the client to use the university LDAP
456 for NSS and Kerberos server for PAM, but one was to change a hard
457 coded DNS domain name in the mklocaluser hook from .intern to
458 .uio.no.&lt;/p&gt;
459
460 &lt;p&gt;This testing was so encouraging, that I went ahead and adjusted the
461 Debian Edu scripts and setup in subversion to centralise the roaming
462 workstation setup a bit more and avoid the hardcoded DNS domain name,
463 so that when I test this tomorrow, I expect to get away with modifying
464 only /etc/sssd/sssd.conf and /etc/ldap.conf to get it to use the
465 university servers.&lt;/p&gt;
466
467 &lt;p&gt;My goal is to get the clients to have no hardcoded settings and
468 fetch all their initial setup during installation and first boot, to
469 allow them to be inserted also into environments where the default
470 setup in Debian Edu has been changed or as with the university, where
471 the environment is different but provides the protocols Debian Edu
472 uses.&lt;/p&gt;
473 </description>
474 </item>
475
476 <item>
477 <title>Circular package dependencies harms apt recovery</title>
478 <link>http://people.skolelinux.org/pere/blog/Circular_package_dependencies_harms_apt_recovery.html</link>
479 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Circular_package_dependencies_harms_apt_recovery.html</guid>
480 <pubDate>Tue, 27 Jul 2010 23:50:00 +0200</pubDate>
481 <description>
482 &lt;p&gt;I discovered this while doing
483 &lt;a href=&quot;http://people.skolelinux.org/pere/blog/Automatic_upgrade_testing_from_Lenny_to_Squeeze.html&quot;&gt;automated
484 testing of upgrades from Debian Lenny to Squeeze&lt;/a&gt;. A few packages
485 in Debian still got circular dependencies, and it is often claimed
486 that apt and aptitude should be able to handle this just fine, but
487 some times these dependency loops causes apt to fail.&lt;/p&gt;
488
489 &lt;p&gt;An example is from todays
490 &lt;a href=&quot;http://people.skolelinux.org/~pere/debian-upgrade-testing//test-20100727-lenny-squeeze-kde-aptitude.txt&quot;&gt;upgrade
491 of KDE using aptitude&lt;/a&gt;. In it, a bug in kdebase-workspace-data
492 causes perl-modules to fail to upgrade. The cause is simple. If a
493 package fail to unpack, then only part of packages with the circular
494 dependency might end up being unpacked when unpacking aborts, and the
495 ones already unpacked will fail to configure in the recovery phase
496 because its dependencies are unavailable.&lt;/p&gt;
497
498 &lt;p&gt;In this log, the problem manifest itself with this error:&lt;/p&gt;
499
500 &lt;blockquote&gt;&lt;pre&gt;
501 dpkg: dependency problems prevent configuration of perl-modules:
502 perl-modules depends on perl (&gt;= 5.10.1-1); however:
503 Version of perl on system is 5.10.0-19lenny2.
504 dpkg: error processing perl-modules (--configure):
505 dependency problems - leaving unconfigured
506 &lt;/pre&gt;&lt;/blockquote&gt;
507
508 &lt;p&gt;The perl/perl-modules circular dependency is already
509 &lt;a href=&quot;http://bugs.debian.org/527917&quot;&gt;reported as a bug&lt;/a&gt;, and will
510 hopefully be solved as soon as possible, but it is not the only one,
511 and each one of these loops in the dependency tree can cause similar
512 failures. Of course, they only occur when there are bugs in other
513 packages causing the unpacking to fail, but it is rather nasty when
514 the failure of one package causes the problem to become worse because
515 of dependency loops.&lt;/p&gt;
516
517 &lt;p&gt;Thanks to
518 &lt;a href=&quot;http://lists.debian.org/debian-devel/2010/06/msg00116.html&quot;&gt;the
519 tireless effort by Bill Allombert&lt;/a&gt;, the number of circular
520 dependencies
521 &lt;a href=&quot;http://debian.semistable.com/debgraph.out.html&quot;&gt;left in Debian
522 is dropping&lt;/a&gt;, and perhaps it will reach zero one day. :)&lt;/p&gt;
523
524 &lt;p&gt;Todays testing also exposed a bug in
525 &lt;a href=&quot;http://bugs.debian.org/590605&quot;&gt;update-notifier&lt;/a&gt; and
526 &lt;a href=&quot;http://bugs.debian.org/590604&quot;&gt;different behaviour&lt;/a&gt; between
527 apt-get and aptitude, the latter possibly caused by some circular
528 dependency. Reported both to BTS to try to get someone to look at
529 it.&lt;/p&gt;
530 </description>
531 </item>
532
533 <item>
534 <title>First Debian Edu test release (alpha0) based on Squeeze is released</title>
535 <link>http://people.skolelinux.org/pere/blog/First_Debian_Edu_test_release__alpha0__based_on_Squeeze_is_released.html</link>
536 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/First_Debian_Edu_test_release__alpha0__based_on_Squeeze_is_released.html</guid>
537 <pubDate>Tue, 27 Jul 2010 17:45:00 +0200</pubDate>
538 <description>
539 &lt;p&gt;I just posted this announcement culminating several months of work
540 with the next Debian Edu release. Not nearly done, but one major step
541 completed.&lt;/p&gt;
542
543 &lt;blockquote&gt;
544 &lt;p&gt;This is the first test release based on Squeeze. The focus of this
545 release is to test the user application selection. To have a look,
546 install the standalone profile and let the developers know if the set
547 of installed packages i.e. applications should be modified. If some
548 user application is missing, or if there are some applications that no
549 longer make sense to be included in Debian Edu, please let us know.
550 Also, if a useful application is missing the translation for your
551 language of choice, please let us know too.&lt;/p&gt;
552
553 &lt;p&gt;In addition, feedback and help to polish the desktop (menus,
554 artwork, starters, etc.) is appreciated. We would like to ship a nice
555 and handy KDE4 desktop targeted for schools out of the box.&lt;/p&gt;
556
557 &lt;p&gt;The other profiles should be installable, but there is a lot more
558 work left to be done before they are ready, so do not expect to
559 much.&lt;/p&gt;
560
561 &lt;p&gt;Changes compared to the lenny based version&lt;/p&gt;
562
563 &lt;ul&gt;
564 &lt;li&gt;Everything from Debian Squeeze
565 &lt;ul&gt;
566 &lt;li&gt;Desktop environment KDE 4.4 =&gt; the new KDE desktop in
567 combination with some new artwork
568 &lt;li&gt;Web browser Iceweasel 3.5
569 &lt;li&gt;OpenOffice.org 3.2
570 &lt;li&gt;Educational toolbox GCompris 9.3
571 &lt;li&gt;Music creator Rosegarden 10.04.2
572 &lt;li&gt;Image editor Gimp 2.6.10
573 &lt;li&gt;Virtual universe Celestia 1.6.0
574 &lt;li&gt;Virtual stargazer Stellarium 0.10.4
575 &lt;li&gt;3D modeler Blender 2.49.2 (new application)
576 &lt;li&gt;Video editor Kdenlive 0.7.7 (new application)
577 &lt;/ul&gt;&lt;/li&gt;
578 &lt;li&gt;Now using Kerberos for password checking (migration not finished).
579 Enabled for:
580 &lt;ul&gt;
581 &lt;li&gt;PAM
582 &lt;li&gt;LDAP
583 &lt;li&gt;IMAP
584 &lt;li&gt;SMTP (sender verification)
585 &lt;/ul&gt;
586 &lt;/li&gt;
587 &lt;li&gt;New experimental roaming workstation profile for laptops.&lt;/li&gt;
588 &lt;li&gt;Show welcome page to users when they first log in. The URL is
589 fetched from LDAP.&lt;/li&gt;
590 &lt;li&gt;New LXDE desktop option, in addition to KDE (default) and Gnome.&lt;/li&gt;
591 &lt;li&gt;General cleanup (not finished)&lt;/li&gt;
592 &lt;/ul&gt;
593 &lt;p&gt;The following features are not working as they should&lt;/p&gt;
594
595 &lt;ul&gt;
596 &lt;li&gt;No web based administration tool for creating users and groups. The
597 scripts ldap-createuser-krb and ldap-add-user-to-group can be used
598 for testing.&lt;/li&gt;
599 &lt;li&gt;DVD installs are missing debian-installer images for the PXE boot,
600 and do not set up the PXE menu on eth0 because of this. LTSP
601 clients should still boot from eth1 on thin client servers.&lt;/li&gt;
602 &lt;li&gt;The restructured KDE menu is not implemented.&lt;/li&gt;
603 &lt;li&gt;The LDAP server setup need to be reviewed for security.&lt;/li&gt;
604 &lt;li&gt;The LDAP directory structure need to be reworked.&lt;/li&gt;
605 &lt;li&gt;Different sets of packages are installed when using the DVD and the
606 netinst CD. More packages are installed using the netinst CD.&lt;/li&gt;
607 &lt;li&gt;The jackd package fail to install. This is believed to be caused by
608 some ongoing transition, and hopefully should be solved soon. The
609 jackd1 package can be installed manually for those that need it.&lt;/li&gt;
610 &lt;li&gt;Some packages lack translations. See
611 http://wiki.debian.org/DebianEdu/Status/Squeeze for updated status,
612 and help out with translations.&lt;/li&gt;
613 &lt;/ul&gt;
614
615 &lt;p&gt;To download this multiarch netinstall release you can use&lt;/p&gt;
616
617 &lt;ul&gt;
618 &lt;li&gt;&lt;a href=&quot;ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso&quot;&gt;ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso&lt;/a&gt;&lt;/li&gt;
619 &lt;li&gt;&lt;a href=&quot;http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso&quot;&gt;http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso&lt;/a&gt;&lt;/li&gt;
620 &lt;li&gt;rsync -avzP ftp.skolelinux.org::skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso&lt;/li&gt;
621 &lt;/ul&gt;
622 &lt;p&gt;To download this multiarch dvd release you can use&lt;/p&gt;
623
624 &lt;ul&gt;
625 &lt;li&gt;&lt;a href=&quot;ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso&quot;&gt;ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso&lt;/a&gt;&lt;/li&gt;
626 &lt;li&gt;&lt;a href=&quot;http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso&quot;&gt;http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso&lt;/a&gt;&lt;/li&gt;
627 &lt;li&gt;rsync -avzP ftp.skolelinux.org::skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso&lt;/li&gt;
628 &lt;/ul&gt;
629
630 &lt;p&gt;There is no source DVD available yet. It will be prepared when we
631 get closer to the final release.&lt;/p&gt;
632
633 &lt;p&gt;The MD5SUM of these images are&lt;/p&gt;
634
635 &lt;ul&gt;
636 &lt;li&gt;3dbf45d59f42a53518b6e3c9ec3b5eb6 debian-edu-6.0.0+edua0-CD.iso&lt;/li&gt;
637 &lt;li&gt;22f2cbfce281d1c6e478be452638675d debian-edu-6.0.0+edua0-DVD.iso&lt;/li&gt;
638 &lt;/ul&gt;
639
640 &lt;p&gt;The SHA1SUM of these images are&lt;/p&gt;
641 &lt;ul&gt;
642 &lt;li&gt;c53d1b69b40cf37cd27aefaf33f6f6a3821bedf0 debian-edu-6.0.0+edua0-CD.iso&lt;/li&gt;
643 &lt;li&gt;2ec29d7db676d59d32197b05c277ffe16348376c debian-edu-6.0.0+edua0-DVD.iso&lt;/li&gt;
644 &lt;/ul&gt;
645 &lt;p&gt;How to report bugs:
646 http://wiki.debian.org/DebianEdu/HowTo/ReportBugsInBugzilla&lt;/p&gt;
647
648 &lt;p&gt;Please direct replies to debian-edu@lists.debian.org&lt;/p&gt;
649 &lt;/blockquote&gt;
650 </description>
651 </item>
652
653 <item>
654 <title>One step closer to single signon in Debian Edu</title>
655 <link>http://people.skolelinux.org/pere/blog/One_step_closer_to_single_signon_in_Debian_Edu.html</link>
656 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/One_step_closer_to_single_signon_in_Debian_Edu.html</guid>
657 <pubDate>Sun, 25 Jul 2010 10:00:00 +0200</pubDate>
658 <description>
659 &lt;p&gt;The last few months me and the other Debian Edu developers have
660 been working hard to get the Debian/Squeeze based version of Debian
661 Edu/Skolelinux into shape. This future version will use Kerberos for
662 authentication, and services are slowly migrated to single signon,
663 getting rid of password questions one at the time.&lt;/p&gt;
664
665 &lt;p&gt;It will also feature a roaming workstation profile with local home
666 directory, for laptops that are only some times on the Skolelinux
667 network, and for this profile a shortcut is created in Gnome and KDE
668 to gain access to the users home directory on the file server. This
669 shortcut uses SMB at the moment, and yesterday I had time to test if
670 SMB mounting had started working in KDE after we added the cifs-utils
671 package. I was pleasantly surprised how well it worked.&lt;/p&gt;
672
673 &lt;p&gt;Thanks to the recent changes to our samba configuration to get it
674 to use Kerberos for authentication, there were no question about user
675 password when mounting the SMB volume. A simple click on the shortcut
676 in the KDE menu, and a window with the home directory popped
677 up. :)&lt;/p&gt;
678
679 &lt;p&gt;One step closer to a single signon solution out of the box in
680 Debian Edu. We already had PAM, LDAP, IMAP and SMTP in place, and now
681 also Samba. Next step is Cups and hopefully also NFS.&lt;/p&gt;
682
683 &lt;p&gt;We had planned a alpha0 release of Debian Edu for today, but thanks
684 to the autobuilder administrators for some architectures being slow to
685 sign packages, we are still missing the fixed LTSP package we need for
686 the release. It was uploaded three days ago with urgency=high, and if
687 it had entered testing yesterday we would have been able to test it in
688 time for a alpha0 release today. As the binaries for ia64 and powerpc
689 still not uploaded to the Debian archive, we need to delay the alpha
690 release another day.&lt;/p&gt;
691
692 &lt;p&gt;If you want to help out with implementing Kerberos for Debian Edu,
693 please contact us on debian-edu@lists.debian.org.&lt;/p&gt;
694 </description>
695 </item>
696
697 <item>
698 <title>Digitale restriksjonsmekanismer fikk meg til å slutte å kjøpe musikk</title>
699 <link>http://people.skolelinux.org/pere/blog/Digitale_restriksjonsmekanismer_fikk_meg_til____slutte____kj__pe_musikk.html</link>
700 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Digitale_restriksjonsmekanismer_fikk_meg_til____slutte____kj__pe_musikk.html</guid>
701 <pubDate>Thu, 22 Jul 2010 23:50:00 +0200</pubDate>
702 <description>
703 &lt;p&gt;For mange år siden slutte jeg å kjøpe musikk-CDer. Årsaken var at
704 musikkbransjen var godt i gang med å selge platene sine med DRM som
705 gjorde at jeg ikke fikk spilt av musikken jeg kjøpte på utstyret jeg
706 hadde tilgjengelig, dvs. min datamaskin. Det var umulig å se på en
707 plate om den var ødelagt eller ikke, og jeg hadde jo allerede en
708 anseelig samling med plater, så jeg bestemme meg for å slutte å gi
709 penger til en bransje som åpenbart ikke respekterte meg.&lt;/p&gt;
710
711 &lt;p&gt;Jeg har mange titalls dager med musikk på CD i dag. Det meste er
712 lagt i et stort arkiv som kan spilles av fra husets datamaskiner (har
713 ikke rukket rippe alt). Jeg ser dermed ikke behovet for å skaffe mer
714 musikk. De fleste av mine favoritter er i hus, og jeg er dermed godt
715 fornøyd.&lt;/p&gt;
716
717 &lt;p&gt;Hvis musikkbransjen ønsker mine penger, så må de demonstrere at de
718 setter pris på meg som kunde, og ikke skremme meg bort med DRM og
719 antydninger om at kundene er kriminelle.&lt;/p&gt;
720
721 &lt;p&gt;Filmbransjen er like ille, men mens musikk gjerne varer lenge, er
722 filmer mer ferskvare. Har dermed ikke helt sluttet å kjøpe filmer, men
723 holder meg til DVD-filmer som kan spilles av på mine Linuxbokser.
724 Kommer neppe til å ta i bruk Blueray, og ei heller de nye DRM-greiene
725 «Ultraviolet» som be annonsert her om dagen.&lt;/p&gt;
726 </description>
727 </item>
728
729 <item>
730 <title>OpenStreetmap one step closer to having routing on its front page</title>
731 <link>http://people.skolelinux.org/pere/blog/OpenStreetmap_one_step_closer_to_having_routing_on_its_front_page.html</link>
732 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/OpenStreetmap_one_step_closer_to_having_routing_on_its_front_page.html</guid>
733 <pubDate>Sun, 18 Jul 2010 16:45:00 +0200</pubDate>
734 <description>
735 &lt;p&gt;Thanks to
736 &lt;a href=&quot;http://feedproxy.google.com/~r/Opengeodata/~3/wUTCzDZk3lc/project-of-the-week-which-way-home&quot;&gt;todays
737 opengeodata blog entry&lt;/a&gt;, I just discovered that the
738 OpenStreetmap.org site have gotten
739 &lt;a href=&quot;http://nroets.dev.openstreetmap.org/demo/index.html?layers=B000FTFTT&quot;&gt;support
740 for calculating routes&lt;/a&gt;. The support is still experimental and
741 only available from the development server, until more experience is
742 gathered on the user interface and any scalability issues.&lt;/p&gt;
743
744 &lt;p&gt;Earlier, the routing I knew about using the OpenStreetmap.org data
745 was provided by &lt;a href=&quot;http://maps.cloudmade.com/&quot;&gt;Cloudmade&lt;/a&gt;,
746 but having it on the main page is required to make everyone aware of
747 the issue. I&#39;ve had people reject Openstreetmap.org as a viable
748 alternative for them because the front page lacked routing support,
749 and I hope their needs will be catered for when routing show up on the
750 www.openstreetmap.org front page.&lt;/p&gt;
751 </description>
752 </item>
753
754 </channel>
755 </rss>