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   5   <title>Petter Reinholdtsen: entries from August 2010</title>
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  13   <h1>
  14        <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  15
  16   </h1>
  17
  18  </div>
  19
  20  <p>Entries from August 2010.</p>
  21
  22
  23 <div class="entry">
  24  <div class="title">
  25  <a href="http://people.skolelinux.org/pere/blog/Debian_Edu_roaming_workstation___at_the_university_of_Oslo.html">Debian Edu roaming workstation - at the university of Oslo</a>
  26  </div>
  27  <div class="date">
  28   2010-08-03 23:30
  29  </div>
  30
  31  <div class="body">
  32
  33 <p>The new roaming workstation profile in Debian Edu/Squeeze is fairly
  34 similar to the laptop setup am I working on using Ubuntu for the
  35 University of Oslo, and just for the heck of it, I tested today how
  36 hard it would be to integrate that profile into the university
  37 infrastructure.  In this case, it is the university LDAP server,
  38 Active Directory Kerberos server and SMB mounting from the Netapp file
  39 servers.</p>
  40
  41 <p>I was pleasantly surprised that the only three files needed to be
  42 changed (/etc/sssd/sssd.conf, /etc/ldap.conf and
  43 /etc/mklocaluser.d/20-debian-edu-config) and one file had to be added
  44 (/usr/share/perl5/Debian/Edu_Local.pm), to get the client working.
  45 Most of the changes were to get the client to use the university LDAP
  46 for NSS and Kerberos server for PAM, but one was to change a hard
  47 coded DNS domain name in the mklocaluser hook from .intern to
  48 .uio.no.</p>
  49
  50 <p>This testing was so encouraging, that I went ahead and adjusted the
  51 Debian Edu scripts and setup in subversion to centralise the roaming
  52 workstation setup a bit more and avoid the hardcoded DNS domain name,
  53 so that when I test this tomorrow, I expect to get away with modifying
  54 only /etc/sssd/sssd.conf and /etc/ldap.conf to get it to use the
  55 university servers.</p>
  56
  57 <p>My goal is to get the clients to have no hardcoded settings and
  58 fetch all their initial setup during installation and first boot, to
  59 allow them to be inserted also into environments where the default
  60 setup in Debian Edu has been changed or as with the university, where
  61 the environment is different but provides the protocols Debian Edu
  62 uses.</p>
  63
  64  </div>
  65  <div class="tags">
  66
  67
  68
  69   Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
  70
  71  </div>
  72 </div>
  73  <div class="padding"></div>
  74
  75 <div class="entry">
  76  <div class="title">
  77  <a href="http://people.skolelinux.org/pere/blog/Autodetecting_Client_setup_for_roaming_workstations_in_Debian_Edu.html">Autodetecting Client setup for roaming workstations in Debian Edu</a>
  78  </div>
  79  <div class="date">
  80   2010-08-07 14:45
  81  </div>
  82
  83  <div class="body">
  84
  85 <p>A few days ago, I
  86 <a href="http://people.skolelinux.org/pere/blog/Debian_Edu_roaming_workstation___at_the_university_of_Oslo.html">tried
  87 to install</a> a Roaming workation profile from Debian Edu/Squeeze
  88 while on the university network here at the University of Oslo, and
  89 noticed how much had to change to get it operational using the
  90 university infrastructure.  It was fairly easy, but it occured to me
  91 that Debian Edu would improve a lot if I could get the client to
  92 connect without any changes at all, and thus let the client configure
  93 itself during installation and first boot to use the infrastructure
  94 around it.  Now I am a huge step further along that road.</p>
  95
  96 <p>With our current squeeze-test packages, I can select the roaming
  97 workstation profile and get a working laptop connecting to the
  98 university LDAP server for user and group and our active directory
  99 servers for Kerberos authentication.  All this without any
 100 configuration at all during installation.  My users home directory got
 101 a bookmark in the KDE menu to mount it via SMB, with the correct URL.
 102 In short, openldap and sssd is correctly configured.  In addition to
 103 this, the client look for http://wpad/wpad.dat to configure a web
 104 proxy, and when it fail to find it no proxy settings are stored in
 105 /etc/environment and /etc/apt/apt.conf.  Iceweasel and KDE is
 106 configured to look for the same wpad configuration and also do not use
 107 a proxy when at the university network.  If the machine is moved to a
 108 network with such wpad setup, it would automatically use it when DHCP
 109 gave it a IP address.</p>
 110
 111 <p>The LDAP server is located using DNS, by first looking for the DNS
 112 entry ldap.$domain.  If this do not exist, it look for the
 113 _ldap._tcp.$domain SRV records and use the first one as the LDAP
 114 server.  Next, it connects to the LDAP server and search all
 115 namingContexts entries for posixAccount or posixGroup objects, and
 116 pick the first one as the LDAP base.  For Kerberos, a similar
 117 algorithm is used to locate the LDAP server, and the realm is the
 118 uppercase version of $domain.</p>
 119
 120 <p>So, what is not working, you might ask.  SMB mounting my home
 121 directory do not work.  No idea why, but suspected the incorrect
 122 Kerberos settings in /etc/krb5.conf and /etc/samba/smb.conf might be
 123 the cause.  These are not properly configured during installation, and
 124 had to be hand-edited to get the correct Kerberos realm and server,
 125 but SMB mounting still do not work. :(</p>
 126
 127 <p>With this automatic configuration in place, I expect a Debian Edu
 128 roaming profile installation would be able to automatically detect and
 129 connect to any site using LDAP and Kerberos for NSS directory and PAM
 130 authentication.  It should also work out of the box in a Active
 131 Directory environment providing posixAccount and posixGroup objects
 132 with UID and GID values.</p>
 133
 134 <p>If you want to help out with implementing these things for Debian
 135 Edu, please contact us on debian-edu@lists.debian.org.</p>
 136
 137  </div>
 138  <div class="tags">
 139
 140
 141
 142   Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 143
 144  </div>
 145 </div>
 146  <div class="padding"></div>
 147
 148 <div class="entry">
 149  <div class="title">
 150  <a href="http://people.skolelinux.org/pere/blog/Testing_if_a_file_system_can_be_used_for_home_directories___.html">Testing if a file system can be used for home directories...</a>
 151  </div>
 152  <div class="date">
 153   2010-08-08 21:20
 154  </div>
 155
 156  <div class="body">
 157
 158 <p>A few years ago, I was involved in a project planning to use
 159 Windows file servers as home directory servers for Debian
 160 Edu/Skolelinux machines.  This was thought to be no problem, as the
 161 access would be through the SMB network file system protocol, and we
 162 knew other sites used SMB with unix and samba as the file server to
 163 mount home directories without any problems.  But, after months of
 164 struggling, we had to conclude that our goal was impossible.</p>
 165
 166 <p>The reason is simply that while SMB can be used for home
 167 directories when the file server is Samba running on Unix, this only
 168 work because of Samba have some extensions and the fact that the
 169 underlying file system is a unix file system.  When using a Windows
 170 file server, the underlying file system do not have POSIX semantics,
 171 and several programs will fail if the users home directory where they
 172 want to store their configuration lack POSIX semantics.</p>
 173
 174 <p>As part of this work, I wrote a small C program I want to share
 175 with you all, to replicate a few of the problematic applications (like
 176 OpenOffice.org and GCompris) and see if the file system was working as
 177 it should.  If you find yourself in spooky file system land, it might
 178 help you find your way out again.  This is the fs-test.c source:</p>
 179
 180 <pre>
 181 /*
 182  * Some tests to check the file system sematics.  Used to verify that
 183  * CIFS from a windows server do not work properly as a linux home
 184  * directory.
 185  * License: GPL v2 or later
 186  *
 187  * needs libsqlite3-dev and build-essential installed
 188  * compile with: gcc -Wall -lsqlite3 -DTEST_SQLITE fs-test.c -o fs-test
 189 */
 190
 191 #define _FILE_OFFSET_BITS 64
 192 #define _LARGEFILE_SOURCE 1
 193 #define _LARGEFILE64_SOURCE 1
 194
 195 #define _GNU_SOURCE /* for asprintf() */
 196
 197 #include &lt;errno.h>
 198 #include &lt;fcntl.h>
 199 #include &lt;stdio.h>
 200 #include &lt;string.h>
 201 #include &lt;stdlib.h>
 202 #include &lt;sys/file.h>
 203 #include &lt;sys/stat.h>
 204 #include &lt;sys/types.h>
 205 #include &lt;unistd.h>
 206
 207 #ifdef TEST_SQLITE
 208 /*
 209  * Test sqlite open, as done by gcompris require the libsqlite3-dev
 210  * package and linking with -lsqlite3.  A more low level test is
 211  * below.
 212  * See also &lt;URL: http://www.sqlite.org./faq.html#q5 >.
 213  */
 214 #include &lt;sqlite3.h>
 215 #define CREATE_TABLE_USERS                                              \
 216   "CREATE TABLE users (user_id INT UNIQUE, login TEXT, lastname TEXT, firstname TEXT, birthdate TEXT, class_id INT ); "
 217 int test_sqlite_open(void) {
 218   char *zErrMsg;
 219   char *name = "testsqlite.db";
 220   sqlite3 *db=NULL;
 221   unlink(name);
 222   int rc = sqlite3_open(name, &db);
 223   if( rc ){
 224     printf("error: sqlite open of %s failed: %s\n", name, sqlite3_errmsg(db));
 225     sqlite3_close(db);
 226     return -1;
 227   }
 228
 229   /* create tables */
 230   rc = sqlite3_exec(db,CREATE_TABLE_USERS, NULL,  0, &zErrMsg);
 231   if( rc != SQLITE_OK ){
 232     printf("error: sqlite table create failed: %s\n", zErrMsg);
 233     sqlite3_close(db);
 234     return -1;
 235   }
 236   printf("info: sqlite worked\n");
 237   sqlite3_close(db);
 238   return 0;
 239 }
 240 #endif /* TEST_SQLITE */
 241
 242 /*
 243  * Demonstrate locking issue found in gcompris using sqlite3.  This
 244  * work with ext3, but not with cifs server on Windows 2003.  This is
 245  * done in the sqlite3 library.
 246  * See also
 247  * &lt;URL:http://www.cygwin.com/ml/cygwin/2001-08/msg00854.html> and the
 248  * POSIX specification
 249  * &lt;URL:http://www.opengroup.org/onlinepubs/009695399/functions/fcntl.html>.
 250  */
 251 int test_gcompris_locking(void) {
 252   struct flock fl;
 253   char *name = "testsqlite.db";
 254   unlink(name);
 255   int fd = open(name, O_RDWR|O_CREAT|O_LARGEFILE, 0644);
 256   printf("info: testing fcntl locking\n");
 257
 258   fl.l_whence = SEEK_SET;
 259   fl.l_pid    = getpid();
 260   printf("  Read-locking 1 byte from 1073741824");
 261   fl.l_start  = 1073741824;
 262   fl.l_len    = 1;
 263   fl.l_type   = F_RDLCK;
 264   if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
 265
 266   printf("  Read-locking 510 byte from 1073741826");
 267   fl.l_start  = 1073741826;
 268   fl.l_len    = 510;
 269   fl.l_type   = F_RDLCK;
 270   if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
 271
 272   printf("  Unlocking 1 byte from 1073741824");
 273   fl.l_start  = 1073741824;
 274   fl.l_len    = 1;
 275   fl.l_type   = F_UNLCK;
 276   if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
 277
 278   printf("  Write-locking 1 byte from 1073741824");
 279   fl.l_start  = 1073741824;
 280   fl.l_len    = 1;
 281   fl.l_type   = F_WRLCK;
 282   if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
 283
 284   printf("  Write-locking 510 byte from 1073741826");
 285   fl.l_start  = 1073741826;
 286   fl.l_len    = 510;
 287   if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
 288
 289   printf("  Unlocking 2 byte from 1073741824");
 290   fl.l_start  = 1073741824;
 291   fl.l_len    = 2;
 292   fl.l_type   = F_UNLCK;
 293   if (0 != fcntl(fd, F_SETLK, &fl) ) printf(" - error!\n"); else printf("\n");
 294
 295   close(fd);
 296   return 0;
 297 }
 298
 299 /*
 300  * Test if permissions of freshly created directories allow entries
 301  * below them.  This was a problem with OpenOffice.org and gcompris.
 302  * Mounting with option 'sync' seem to solve this problem while
 303  * slowing down file operations.
 304  */
 305 int test_subdirectory_creation(void) {
 306 #define LEVELS 5
 307   char *path = strdup("test");
 308   char *dirs[LEVELS];
 309   int level;
 310   printf("info: testing subdirectory creation\n");
 311   for (level = 0; level &lt; LEVELS; level++) {
 312     char *newpath = NULL;
 313     if (-1 == mkdir(path, 0777)) {
 314       printf("  error: Unable to create directory '%s': %s\n",
 315              path, strerror(errno));
 316       break;
 317     }
 318     asprintf(&newpath, "%s/%s", path, "test");
 319     free(path);
 320     path = newpath;
 321   }
 322   return 0;
 323 }
 324
 325 /*
 326  * Test if symlinks can be created.  This was a problem detected with
 327  * KDE.
 328  */
 329 int test_symlinks(void) {
 330   printf("info: testing symlink creation\n");
 331   unlink("symlink");
 332   if (-1 == symlink("file", "symlink"))
 333     printf("  error: Unable to create symlink\n");
 334   return 0;
 335 }
 336
 337 int main(int argc, char **argv) {
 338   printf("Testing POSIX/Unix sematics on file system\n");
 339   test_symlinks();
 340   test_subdirectory_creation();
 341 #ifdef TEST_SQLITE
 342   test_sqlite_open();
 343 #endif /* TEST_SQLITE */
 344   test_gcompris_locking();
 345   return 0;
 346 }
 347 </pre>
 348
 349 <p>When everything is working, it should print something like
 350 this:</p>
 351
 352 <pre>
 353 Testing POSIX/Unix sematics on file system
 354 info: testing symlink creation
 355 info: testing subdirectory creation
 356 info: sqlite worked
 357 info: testing fcntl locking
 358   Read-locking 1 byte from 1073741824
 359   Read-locking 510 byte from 1073741826
 360   Unlocking 1 byte from 1073741824
 361   Write-locking 1 byte from 1073741824
 362   Write-locking 510 byte from 1073741826
 363   Unlocking 2 byte from 1073741824
 364 </pre>
 365
 366 <p>I do not remember the exact details of the problems we saw, but one
 367 of them was with locking, where if I remember correctly, POSIX allow a
 368 read-only lock to be upgraded to a read-write lock without unlocking
 369 the read-only lock (while Windows do not).  Another was a bug in the
 370 CIFS/SMB client implementation in the Linux kernel where directory
 371 meta information would be wrong for a fraction of a second, making
 372 OpenOffice.org fail to create its deep directory tree because it was
 373 not allowed to create files in its freshly created directory.</p>
 374
 375 <p>Anyway, here is a nice tool for your tool box, might you never need
 376 it. :)</p>
 377
 378  </div>
 379  <div class="tags">
 380
 381
 382
 383   Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 384
 385  </div>
 386 </div>
 387  <div class="padding"></div>
 388
 389 <div class="entry">
 390  <div class="title">
 391  <a href="http://people.skolelinux.org/pere/blog/No_hardcoded_config_on_Debian_Edu_clients.html">No hardcoded config on Debian Edu clients</a>
 392  </div>
 393  <div class="date">
 394   2010-08-09 20:15
 395  </div>
 396
 397  <div class="body">
 398
 399 <p>As reported earlier, the last few days I have looked at how Debian
 400 Edu clients are configured, and tried to get rid of all hardcoded
 401 configuration settings on the clients.  I believe the work to be
 402 mostly done, and the clients seem to work just fine with dynamically
 403 generated configuration.</p>
 404
 405 <p>What is the point, you might ask?  The point is to allow a Debian
 406 Edu desktop to integrate into an existing network infrastructure
 407 without any manual configuration.</p>
 408
 409 <p>This is what happens when installing a Debian Edu client here at
 410 the University of Oslo using PXE.  With the PXE installation, I am
 411 asked for language (Norwegian Bokmål), locality (Norway) and keyboard
 412 layout (no-latin1), Debian Edu profile (Roaming Workstation), if I
 413 accept to reformat the hard drive (yes), if I want to submit info to
 414 popcon.debian.org (no) and root password (secret).  After answering
 415 these questions, the installer goes ahead and does its thing, and
 416 after around 50 minutes it is done.  I press enter to finish the
 417 installation, and the machine reboots into KDE.  When the machine is
 418 ready and kdm asks for login information, I enter my university
 419 username and password, am told by kdm that a local home directory has
 420 been created and that I must log in again, and finally log in with the
 421 same username and password to the KDE 4.4 desktop.  At no point during
 422 this process did it ask for university specific settings, and all the
 423 required configuration was dynamically detected using information
 424 fetched via DHCP and DNS.  The roaming workstation is now ready for
 425 use.</p>
 426
 427 <p>How was this done, you might wonder?  First of all, here is the
 428 list of things that need to be configured on the client to get it
 429 working properly out of the box:</p>
 430
 431 <ul>
 432 <li>IP address/netmask and DNS server.</li>
 433 <li>Web proxy URL.</li>
 434 <li>LDAP server for NSS directory information (user, group, etc).</li>
 435 <li>Kerberos server for PAM password checking.</li>
 436 <li>SMB mount point to access the network home directory. (*)</li>
 437 <li>Central syslog server to send syslog messages to. (*)</li>
 438 <li>Sitesummary collector URL to submit info to central server. (*)</li>
 439 </ul>
 440
 441 <p>(Hm, did I forget anything?  Let me knew if I did.)</p>
 442
 443 <p>The points marked (*) are not required to be able to use the
 444 machine, but needed to provide central storage and allowing system
 445 administrators to track their machines.  Since yesterday, everything
 446 but the sitesummary collector URL is dynamically discovered at boot
 447 and installation time in the svn version of Debian Edu.</p>
 448
 449 <p>The IP and DNS setup is fetched during boot using DHCP as usual.
 450 When a DHCP update arrives, the proxy setup is updated by looking for
 451 http://wpat/wpad.dat and using the content of this WPAD file to
 452 configure the http and ftp proxy in /etc/environment and
 453 /etc/apt/apt.conf.  I decided to update the proxy setup using a DHCP
 454 hook to ensure that the client stops using the Debian Edu proxy when
 455 it is moved outside the Debian Edu network, and instead uses any local
 456 proxy present on the new network when it moves around.</p>
 457
 458 <p>The DNS names of the LDAP, Kerberos and syslog server and related
 459 configuration are generated using DNS information at boot.  First the
 460 installer looks for a host named ldap in the current DNS domain.  If
 461 not found, it looks for _ldap._tcp SRV records in DNS instead.  If an
 462 LDAP server is found, its root DSE entry is requested and the
 463 attributes namingContexts and defaultNamingContext are used to
 464 determine which LDAP base to use for NSS.  If there are several
 465 namingContexts attibutes and the defaultNamingContext is present, that
 466 LDAP subtree is used as the base.  If defaultNamingContext is missing,
 467 the subtrees listed as namingContexts are searched in sequence for any
 468 object with class posixAccount or posixGroup, and the first one with
 469 such an object is used as the LDAP base.  For Kerberos, a similar
 470 search is done by first looking for a host named kerberos, and then
 471 for the _kerberos._tcp SRV record.  I've been unable to find a way to
 472 look up the Kerberos realm, so for this the upper case string of the
 473 current DNS domain is used.</p>
 474
 475 <p>For the syslog server, the hosts syslog and loghost are searched
 476 for, and the _syslog._udp SRV record is consulted if no such host is
 477 found.  This algorithm works for both Debian Edu and the University of
 478 Oslo.  A similar strategy would work for locating the sitesummary
 479 server, but have not been implemented yet.  I decided to fetch and
 480 save these settings during installation, to make sure moving to a
 481 different network does not change the set of users being allowed to
 482 log in nor the passwords required to log in.  Usernames and passwords
 483 will be cached by sssd when the user logs in on the Debian Edu
 484 network, and will not change as the laptop move around.  For a
 485 non-roaming machine, there is no caching, but given that it is
 486 supposed to stay in place it should not matter much.  Perhaps we
 487 should switch those to use sssd too?</p>
 488
 489 <p>The user's SMB mount point for the network home directory is
 490 located when the user logs in for the first time.  The LDAP server is
 491 consulted to look for the user's LDAP object and the sambaHomePath
 492 attribute is used if found.  If it isn't found, the home directory
 493 path fetched from NSS is used instead.  Assuming the path is of the
 494 form /site/server/directory/username, the second part is looked up in
 495 DNS and used to generate a SMB URL of the form
 496 smb://server.domain/username.  This algorithm works for both Debian
 497 edu and the University of Oslo.  Perhaps there are better attributes
 498 to use or a better algorithm that works for more sites, but this will
 499 do for now. :)</p>
 500
 501 <p>This work should make it easier to integrate the Debian Edu clients
 502 into any LDAP/Kerberos infrastructure, and make the current setup even
 503 more flexible than before.  I suspect it will also work for thin
 504 client servers, allowing one to easily set up LTSP and hook it into a
 505 existing network infrastructure, but I have not had time to test this
 506 yet.</p>
 507
 508 <p>If you want to help out with implementing these things for Debian
 509 Edu, please contact us on debian-edu@lists.debian.org.</p>
 510
 511 <p>Update 2010-08-09: Simon Farnsworth gave me a heads-up on how to
 512 detect Kerberos realm from DNS, by looking for _kerberos TXT entries
 513 before falling back to the upper case DNS domain name.  Will have to
 514 implement it for Debian Edu. :)</p>
 515
 516  </div>
 517  <div class="tags">
 518
 519
 520
 521   Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 522
 523  </div>
 524 </div>
 525  <div class="padding"></div>
 526
 527 <div class="entry">
 528  <div class="title">
 529  <a href="http://people.skolelinux.org/pere/blog/Rob_Weir__How_to_Crush_Dissent.html">Rob Weir: How to Crush Dissent</a>
 530  </div>
 531  <div class="date">
 532   2010-08-15 22:20
 533  </div>
 534
 535  <div class="body">
 536
 537 <p>I found the notes from Rob Weir on
 538 <a href="http://feedproxy.google.com/~r/robweir/antic-atom/~3/VGb23-kta8c/how-to-crush-dissent.html">how
 539 to crush dissent</a> matching my own thoughts on the matter quite
 540 well.  Highly recommended for those wondering which road our society
 541 should go down.  In my view we have been heading the wrong way for a
 542 long time.</p>
 543
 544  </div>
 545  <div class="tags">
 546
 547
 548
 549   Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>.
 550
 551  </div>
 552 </div>
 553  <div class="padding"></div>
 554
 555 <div class="entry">
 556  <div class="title">
 557  <a href="http://people.skolelinux.org/pere/blog/2_Spykee_roboter_i_hus__n___skal_det_lekes.html">2 Spykee-roboter i hus, nå skal det lekes</a>
 558  </div>
 559  <div class="date">
 560   2010-08-18 13:30
 561  </div>
 562
 563  <div class="body">
 564
 565 <p>Jeg kjøpte nettopp to
 566 <a href="http://www.spykee-robot.com/">Spykee</a>-roboter, for test og
 567 leking.  Kjøpte to da det var så billige, og gir meg mulighet til å
 568 eksperimentere uten å være veldig redd for å ødelegge alt ved å bytte
 569 ut firmware og slikt.  Oppdaget at lekebutikken på Bryn senter hadde
 570 en liten stabel på lager som de ikke hadde klart å selge ut etter
 571 fjorårets juleinnkjøp, og var villig til å selge for en femtedel av
 572 vanlig pris.  Jeg, Ronny og Jarle har skaffet oss restbeholdningen, og
 573 det blir morsomt å se hva vi får ut av dette.</p>
 574
 575 <p>Roboten har belter styrt av to motorer, kamera, høytaler, mikrofon
 576 og wifi-tilkobling.  Det hele styrt av en GPL-lisensiert databoks som
 577 jeg mistenker kjører linux.  Firmware-kildekoden ble visst publisert i
 578 mai.  Eneste utfordringen er at kontroller-programvaren kun finnes til
 579 Windows, men det må en kunne jobbe seg rundt når vi har kildekoden til
 580 firmwaren. :)</p>
 581
 582 <ul>
 583 <li><a href="http://en.wikipedia.org/wiki/Spykee">Wikipedia-oppføring</a></li>
 584 <li><a href=http://www.spykeeworld.com/spykee/US/freeSoftware.html">Nedlasting av firmware-kilden</a></li>
 585 <li><a href="http://wiki.nuug.no/grupper/robot">prosjektwiki hos NUUG</a></li>
 586 </ul>
 587
 588  </div>
 589  <div class="tags">
 590
 591
 592
 593   Tags: <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>, <a href="http://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 594
 595  </div>
 596 </div>
 597  <div class="padding"></div>
 598
 599 <div class="entry">
 600  <div class="title">
 601  <a href="http://people.skolelinux.org/pere/blog/Robot__reis_deg___.html">Robot, reis deg...</a>
 602  </div>
 603  <div class="date">
 604   2010-08-21 22:10
 605  </div>
 606
 607  <div class="body">
 608
 609 <p>I dag fikk jeg endelig tittet litt på mine nyinnkjøpte roboter, og
 610 har brukt noen timer til å google etter interessante referanser og
 611 aktuell kildekode for bruk på Linux.  Det mest lovende så langt er
 612 <a href="http://ispykee.toyz.org/">ispykee</a>, som har en
 613 BSD-lisensiert linux-daemon som står som mellomledd mellom roboter på
 614 lokalnettet og en sentral tjeneste der en iPhone kan koble seg opp for
 615 å fjernstyre roboten.  Linux-daemonen implementerer deler av
 616 protokollen som roboten forstår.  Etter å ha knotet litt med å oppnå
 617 kontakt med roboten (den oppretter et eget ad-hoc wifi-nett, så jeg
 618 måtte gå av mitt vanlige nett for å få kontakt), og kommet frem til at
 619 den lytter på IP-port 9000 og 9001, gikk jeg i gang med å finne ut
 620 hvordan jeg kunne snakke med roboten vha. disse portene.  Robotbiten
 621 av protokollen er publisert av produsenten med GPL-lisens, slik at det
 622 er mulig å se hvordan protokollen fungerer.  Det finnes en java-klient
 623 for Android som så ganske snasen ut, men fant ingen kildekode for
 624 denne.  Derimot hadde iphone-løsningen kildekode, så jeg tok
 625 utgangspunkt i den.</p>
 626
 627 <p>Daemonen ville i utgangspunktet forsøke å kontakte den sentrale
 628 tjenesten som iphone-programmet kobler seg til.  Jeg skrev dette om
 629 til i stedet å sette opp en nettverkstjeneste på min lokale maskin,
 630 som jeg kan koble meg opp til med telnet og gi kommandoer til roboten
 631 (act, forward, right, left, etc).  Det involverte i praksis å bytte ut
 632 socket()/connect() med socket()/bind()/listen()/accept() for å gjøre
 633 klienten om til en tjener.</p>
 634
 635 <p>Mens jeg har forsøkt å få roboten til å bevege seg har min samboer
 636 skrudd sammen resten av roboten for å få montert kamera og plastpynten
 637 (armer, plastfiber for lys).  Nå er det hele montert, og roboten er
 638 klar til bruk.  Må få flyttet den over til mitt vanlige trådløsnett
 639 før det blir praktisk, men de bitene av protokollen er ikke
 640 implementert i ispykee-daemonen, så der må jeg enten få tak i en mac
 641 eller en windows-maskin, eller implementere det selv.</p>
 642
 643 <p>Vi var tre som kjøpte slike roboter, og vi har blitt enige om å
 644 samle notater og referanser på <a
 645 href="http://wiki.nuug.no/grupper/robot/">NUUGs wiki</a>.  Ta en titt
 646 der hvis du er nysgjerrig.</p>
 647
 648  </div>
 649  <div class="tags">
 650
 651
 652
 653   Tags: <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>, <a href="http://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 654
 655  </div>
 656 </div>
 657  <div class="padding"></div>
 658
 659  <p style="text-align: right;"><a href="08.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS Feed" width="36" height="14"></a></p>
 660
 661
 662
 663 <div id="sidebar">
 664
 665 <h2>Archive</h2>
 666 <ul>
 667
 668 <li>2010
 669 <ul>
 670
 671 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 672
 673 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 674
 675 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 676
 677 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 678
 679 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 680
 681 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 682
 683 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 684
 685 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (7)</a></li>
 686
 687 </ul></li>
 688
 689 <li>2009
 690 <ul>
 691
 692 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 693
 694 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 695
 696 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 697
 698 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 699
 700 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 701
 702 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 703
 704 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 705
 706 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 707
 708 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 709
 710 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 711
 712 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 713
 714 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 715
 716 </ul></li>
 717
 718 <li>2008
 719 <ul>
 720
 721 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 722
 723 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 724
 725 </ul></li>
 726
 727 </ul>
 728
 729
 730
 731 <h2>Tags</h2>
 732 <ul>
 733
 734  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (11)</a></li>
 735
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 737
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 739
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 741
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 743
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 745
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 747
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 749
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 751
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 753
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 755
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 757
 758  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 759
 760  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (5)</a></li>
 761
 762  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (73)</a></li>
 763
 764  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (95)</a></li>
 765
 766  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (14)</a></li>
 767
 768  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (15)</a></li>
 769
 770  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (10)</a></li>
 771
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 773
 774  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 775
 776  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (11)</a></li>
 777
 778  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (3)</a></li>
 779
 780  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (13)</a></li>
 781
 782  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (1)</a></li>
 783
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 785
 786  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (1)</a></li>
 787
 788  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (7)</a></li>
 789
 790 </ul>
 791
 792 </div>
 793 </body>
 794 </html>