lun 2 apr 2012

Lexmark driver demon log: the final solution

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Sometimes I do stupid things, like looking inside my syslog, even if the system seems to work correctly. Last week I have done exactly this stupid thing and I saw this log repeated each 20 seconds:

Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/demon.cpp   : 234  main                 — Checking for USB scanners…
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 79   getScanners          — ::::::::::::::: METHOD START :::::::::::::::
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 213  getUsbScanners       — ::::::::::::::: METHOD START :::::::::::::::
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 221  getUsbScanners       — finding attached HID devices…
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 131  getHidDevices        — ::::::::::::::: METHOD START :::::::::::::::
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev0. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev1. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev2. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev3. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev4. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev5. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev6. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev7. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev8. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev9. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev10. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev11. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev12. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev13. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev14. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/usb/hiddev15. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev0. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev1. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev2. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev3. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev4. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev5. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev6. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev7. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev8. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev9. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev10. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev11. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev12. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev13. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev14. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hiddev15. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev0. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev1. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev2. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev3. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev4. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev5. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev6. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev7. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev8. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev9. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev10. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev11. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev12. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev13. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev14. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 158  getHidDevices        — failed in opening HIDDEV file: /dev/hid/usb/hiddev15. No such file or directory
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 197  getHidDevices        — ::::::::::::::: METHOD END :::::::::::::::
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 223  getUsbScanners       — total HID devices found: 0
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 226  getUsbScanners       — ::::::::::::::: METHOD END :::::::::::::::
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 92   getScanners          — getUsbScanners successful
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/discovery.c : 125  getScanners          — ::::::::::::::: METHOD END :::::::::::::::
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/demon.cpp   : 240  main                 — usb scanners found is 0
Apr  2 10:55:53 luigi-ThinkPad-T510 demond: [P:2377 T:-1220327728] src/demon.cpp   : 309  main                 — End of checking for USB scanners.

At first I thought “Oh my god, what is happening to my laptop? It’s going to break down!!!” and I almost started to cry (no it’s not true, it a joke. I just thought: “why do developers write silly things everywhere? Deamed me that I took a look inside the syslog !”).

So googling arround for a solution I found only a guy with the same issue and no solution at all, sure very few people look inside the syslog.

Today I had some time to spend to remove this crap from the log, and finally I found the solution, or at least I think it could be the solution, becouse by now I didn’t test if everything work well with my lexmark all in one printer/scanner.

Ok, This is my solution; open and edit the file /etc/X11/Xsession.d/99demon2. This is the original content:

DAEMON=/usr/local/lexmark/legacy/bin/demond
NAME=demond
export ENABLE_D_LOG=1
DESC=”Device Monitor”

${DAEMON} lexmark > /dev/null 2>&1 &

Replace the “export ENABLE_D_LOG=1″ with “export ENABLE_D_LOG=0″.

That’s all. To make it work you need to log off and start a new X11 session.

 

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lun 2 apr 2012

eCryptfs/ext4 issue

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Some days ago, playing with some kernel modules I broke the suspend subsystem of my laptop, so a hard reset is needed each time I try to suspend my laptop. Nothing too bad, but with ext4 this could lead to filesystem corruption, and in deed this happend.

Looking at the dmesg log i saw thios two errors repeated many times:

[  761.247262] Valid eCryptfs headers not found in file header region or xattr region, inode 1179676
[  761.247265] Either the lower file is not in a valid eCryptfs format, or the key could not be retrieved. Plaintext passthrough mode is not enabled; returning -EIO

Googling arround I found a possible bug with a possible solution, the bug seems to be related to 0 size files, so I tried the suggested command by my own:

find . -xdev -size 0c -exec ls ‘{}’ \; | wc -l

The command generated some permission issues, some files had root permisisons so first I had to corret this problems, with a chown:

Some days ago, playing with some kernel modules I broke the suspend subsystem of my laptop, so a hard reset is needed each time I try to suspend my laptop. Nothing too bad, but with ext4 this could lead to filesystem corruption, and in deed this happend.

Looking at the dmesg log i saw thios two errors repeated many times:

[  761.247262] Valid eCryptfs headers not found in file header region or xattr region, inode 1179676
[  761.247265] Either the lower file is not in a valid eCryptfs format, or the key could not be retrieved. Plaintext passthrough mode is not enabled; returning -EIO

Googling arround I found a possible bug with a possible solution, the bug seems to be related to 0 size files, so I tried the suggested command by my own:

find . -xdev -size 0c -exec ls ‘{}’ \; | wc -l

The command generated some permission issues, some files had root permisisons so first I had to corret this problems, with a chown:

sudo chown luigi.luigi /home/luigi -R

And this command generated some  errors:

chown: cambiamento del proprietario di “/home/luigi/.cache/zeitgeist/daemon.log”: Errore di input/output
chown: cambiamento del proprietario di “/home/luigi/.cache/desktop-couch/desktop-couchdb.stderr.1″: Errore di input/output
chown: cambiamento del proprietario di “/home/luigi/.cache/desktop-couch/desktop-couchdb.stdout.1″: Errore di input/output
chown: cambiamento del proprietario di “/home/luigi/.cache/desktop-couch/desktop-couchdb.log.1″: Errore di input/output
chown: cambiamento del proprietario di “/home/luigi/.cache/desktop-couch/desktop-couchdb.pid”: Errore di input/output
chown: cambiamento del proprietario di “/home/luigi/.thunderbird/4bj3pb97.default/global-messages-db.sqlite-journal”: Errore di input/output

Looking at the dmesg I found out that each time I tried to read one on these file I got an error. Searching for 0 size files leads me to more than 700 files, but the error isn’t so spread to be reconducted to 700 files.

These files have in deed 0 byte size and deleting only these files solved the issue. So don’t follow the reported soluting for bug #372014 because you will delete many files which doesn’t need to be deleted.

You don’t need to search for 0 size files but, for files which has been corrupted by ext4 and cannot be decrypted, the only way to find this files is to open them in any way. (cat or chown or anything else)

 

 

 

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dom 8 gen 2012

Using new imon devinput with lirc

Posted by admin under Informatica, Mythtv
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I don’t know exacly untile when but the imon lcd support has been merged  into the linux kernel using devinput.

This means that if you want to use the lirc_imon driver you need to blacklist the imon driver shipped with the kernel. You just need to add the following lines in the /etc/modprobe.d/blacklist.conf file:

blacklist rc_imon_pad

blacklist imon

After this you can proceed followingone of the lirc guides related to imon you find on the web.

But if you want to use the new devinput module, which in fact make thinks easier, you just leave the modules as they are and just edit the Hardware.conf file (/etc/lirc/hardware.conf):

# /etc/lirc/hardware.conf
#
#Chosen Remote Control
REMOTE=”Linux input layer (/dev/input/eventX)”
REMOTE_MODULES=”"
REMOTE_DRIVER=”devinput”
REMOTE_DEVICE=”/dev/input/by-id/usb-15c2_0038-event-if00″
REMOTE_SOCKET=”"
REMOTE_LIRCD_CONF=”devinput/lircd.conf.devinput”
REMOTE_LIRCD_ARGS=”"

#Enable lircd
START_LIRCD=”true”

And in the lirc configuration file /etc/lirc/lircd.conf you should put this line:

#Configuration for the Linux input layer (/dev/input/eventX) remote:
include “/usr/share/lirc/remotes/devinput/lircd.conf.devinput”

This work good on my ubutu 11.10, perhaps you need to adjust some paths if your distro is different.

PLS NOTE Done this way the knob on my antec fusion doesn’t work neigther the blue key on the remote. The kno generates events on a different device: /dev/input/by-id/usb-15c2_0038-event-mouse

So you have to chain two distinct lirc servers togethere:

/usr/sbin/lircd –pidfile=/var/run/lirc/lircd1.pid –output=/var/run/lirc/lircd1 –driver=devinput –device=/dev/input/by-id/usb-15c2_0038-event-mouse –listen/usr/sbin/lircd –output=/var/run/lirc/lircd –driver=devinput –device=/dev/input/by-id/usb-15c2_0038-event-if00 –connect=localhost 8765

This way you find events of both devices on the socket /var/run/lirc/lircd.

Due to a driver bug, which i will investigate, the knob gets temporarly disabled if you press some particular key. For example if you press the yellow tv button the kno will not work anymore, until you press a number button of the remote.

To make the two instances of lirc to startup at boot time i added an upstart script /etc/init/htpc-lirc.conf:

description    ”HTPC lirc daemon”

start on (net-device-up
and local-filesystems
and runlevel [2345])
stop on runlevel [016]

script
mkdir /var/run/lirc -p
/usr/sbin/lircd –pidfile=/var/run/lirc/lircd1.pid –output=/var/run/lirc/lircd1 –driver=devinput –device=/dev/input/by-id/usb-15c2_0038-event-mouse –listen
/usr/sbin/lircd –output=/var/run/lirc/lircd –driver=devinput –device=/dev/input/by-id/usb-15c2_0038-event-if00 –connect=localhost:8765
end script

Finally link it init.d

ln -s /lib/init/upstart-job /etc/init.d/htpc-lirc

 

 

 

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mer 4 gen 2012

Malagiustizia

Posted by admin under Opinioni
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Il Tribunale del Riesame di Napoli ha annullato l’ordinanza di carcerazione per Gaetano Riina, fratello di Totò, perché il GIP ha copiato il testo dal PM introducendo diversi errori semantici.
Fosse capitato a un comune mortale, avrebbe quantomeno perso l’incarico o il ruolo che ricopre.

Ecco alcune fonti:

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ven 29 apr 2011

PCLZIP_ERR_BAD_FORMAT (-10) : Invalid block size : 40

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Have this issue in php? In /etc/php.ini comment out:
; mbstring.func_overload = 7

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ven 29 apr 2011

SSD journaling and ro remount

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I recently upgraded my laptop with a brand new SSD, my first two impressions are: much much faster, much much instable.
Yes that’s right, instable. My first try with SSD is was with a HANA SSD 8G (model: HLSM008G), does’t work on linux. I bought this drive on ebay just to make some tries with an economic disk, and eventually install it for use with mythtv as boot disk. Never do this, never buy HANA if you plan to use it on linux. It simply doesn’t even install you get a kernel panic. As I see now the product has been removed from ebay.

My second try is a OCZ Agility II, installed on my htpc with mythtv. On the same pc i had two 500GB HDD and an optical drive. One of the two HDD’s randomly freezes at boot time with the OCZ installed. That means 2 boot every 3 this HDD could not be mounted. I had to remove it. The second issue with the same OCD Agility where some occasionally errors syncing the journal with consequent remount in ro exactly while watching the clue scene of a film. Googling around i found somebody saying that the journal does not have sense in a SSD. In fact if the system crashes the check time on an SSD is ridiculous, so the benefits are irrelevant. So i removed the journal and the issue seem to be gone.

Meanwhile I bought a second OCZ Vertex II for my laptop, work grate, but for performance reasons I decided to remove the journal from ext4. To do so I needed to mount the disk in ro mode.
Easy:

sodo mount -o remount,ro /dev/sda1

No way!! Even booting the system in maintanace mode mount cannot remount in ro if disk is busy.

So it is some more complicate, this is what I had to do:

  • nano /etc/fstab
  • UUID=… / ext4 ro,errors=remount-ro 0 1
  • reboot

    • After reboot:

  • tune2fs -O ^has_journal /dev/sda1
  • mount -o remount,rw /dev/sda1
  • nano /etc/fstab
  • remove ro option

Linux is always a step behind.

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ven 18 feb 2011

Mysql bug parade

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Ok, just to tell the truth this is not a real bug parade, but today I’m struggling with many different bugs. The worst thing is that each time you spend a lot of time trying to figure out what is wrong in your code. So when there is a bug in something like mysql the first step is a review of your own code. After loosing time in trying to find the bug you reach the point where the assertion “my code is correct” is true.

What next? Google and spend some hours googling. Finally in a remote ranked page at position 232 of the google result you find a response of an anonymous developer who answers in the year 2009 to  question posted in year 2005. The solution proposed seems very silly. Absurd. But you are desperate. So you try the solution and…IT WORKS!!!

 

  • Alter table errno:150 [solved]

alter table failure add index FKBF3C318AB88FBECE (idsent),add constraint FKBF3C318AB88FBECE foreign key (idsent) references sent_mail (idsent);

raises an error:  Can’t create table ‘mercurius.#sql-61c_4a’ (errno: 150)
solution:
set foreign_key_checks = 0 ;
alter table failure add index FKBF3C318AB88FBECE (idsent),add constraint FKBF3C318AB88FBECE foreign key (idsent) references sent_mail (idsent);
set foreign_key_checks = 1;
Works!
  • Alter table errno:150 [unsolved]
Same issue as above: alter table QRTZ_JOB_LISTENERS add index FK2E3C7E25EC364202 (JOB_GROUP, JOB_NAME),
add constraint FK2E3C7E25EC364202 foreign key (JOB_GROUP, JOB_NAME) references QRTZ_JOB_DETAILS (JOB_GROUP, JOB_NAME);
raises an error:  Can’t create table ‘mercurius.#sql-61c_4a’ (errno: 150)
same solution as above doesn’t work!
  • Insert and incorrect mysqld_stmt_execute
A standard prepared statement
insert into … values(?,?,?)… raises an exception.
java.lang.RuntimeException: Unable to continue: Error while commiting the transaction
which is caused by a
Caused by: java.sql.BatchUpdateException: Incorrect arguments to mysqld_stmt_execute
adding the parameter useServerPrepStmts=false to the connection works:
jdbc:mysql://localhost:3306/mercurius?useServerPrepStmts=false

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mar 5 ott 2010

Dare importanza a chi non ne ha

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Pensavo di usare il titolo “L’importanza di dare importanza a chi non ha importanza” ma poi mi è sembrato un po troppo ripetitivo, carino, ma ripetitivo.

All’università in diverse occasioni mi hanno insegnato che spesso le persone meno influenti sono quelle che posso creare le maggiori difficoltà. Nel corso di sicurezza informatica tra i diversi approcci per violare un sistema era suggerito quello di corrompere il personale interno, il libro di testo suggeriva di corrompere il personale delle pulizie, spesso sottopagato, con libero accesso anche a locali riservati e ai pc lasciati abbandonati di notte.

Il corso di marketing invece individuava i centralinisti e portieri come persona che possono bloccare il contatto con le persone desiderate o se debitamente stimolate agevolare l’incontro con l’obiettivo della strategia commerciale.

A leggere quei passaggi sembrava di vivere in un modo di mata hari, la sensazione che fossero ispirati a James Bond piuttosto che alla realtà non me l’ha mai tolta nessuno.

Devo però ammettere che l’esperienza mi sta dando torto. In diverse occasioni mi è capitato che interi gruppi di lavoro venissero bloccati da persone che non hanno ruolo decisionale e rivestono ruoli chiave.

L’ultimo episodio in ordine cronologico è di un sistemista che lavora nell’area IT di un importante banca. Avrebbe gradito essere coinvolto nel progetto fin dalle fasi iniziali. Con questa frase ha aperto la riunione in cui non avremmo dovuto fornirgli le indicazioni su come metter online l’applicazione.  Errore enorme. No dare a lui le indicazioni senza neppure averlo consultato prima? In tutti i posti dove sono stato il sistemista prende il lavoro e lo pubblica sui server. Lui no, i sui server sono più delicati di quelli di altri e sono più carchi di quelli da altri. Ha chiesto la documentazione tecnica, schermi di progetto, librerie utilizzate, spiegazioni sulle scelte operate. Una settimana di blocco attività per evadere le sue richieste e un’ulteriore settimana di rallentamenti vari. Non dargli importanza ci è costato 2 settimane di ritardo. E nella riunione finale non ha potuto trattenere un sorriso di soddisfazione “Se mi aveste contattato dall’inizio non avremmo avreste avuto tutti questi problemi”. Mava…

Quinti mai sottovalutare le persone coinvolte anche marginalmente, chiunque può sempre mettersi di traverso

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lun 2 ago 2010

Perché un blog

Posted by admin under Opinioni
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Ho sempre pensato che scrivere su un blog sia una grossa perdita di tempo e ho sempre ritenuto che chi scrive su un blog lo fa perché non sa come passare il tempo.

In realtà comunicare bene è importante tanto quanto saper fare le cose bene. Si possono realizzare i migliori prodotti del mondo, ma se nessuno sa che esistono e cosa possono fare nessuno mai li comprerà.

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mar 27 lug 2010

Strange locale things happen under Tomcat/Jasper

Posted by admin under Informatica
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I recently installed a webapp which uses tomcat and jasper on one of my server. Everything worked well until a template used some special chars, I got the ‘?’ chars which indicate the typical encoding issue.

Everything seemed correct, DB in UTF-8, virtual machine started with -Dfile.encoding=UTF-8, application in UTF-8, data files in UTF-8.

After an hour spend in all these checks I tried an “export LANG=it_IT.utf8” in my linux environment. Everything worked well.

Where is the point? Very simple, some jar don’t look in the JVM system properties but look for the native locale in the linux enviroment. This causes portability issues and lost of time in solving stupid problems.

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