Today, the 20th of May, Jolla unveiled its first, very reasonably-priced (under 400 €, VAT included!) and modular device.

Here are the specs:

- 4.5 '' display

- dual core,

- 4G,

- 16 GB expandable through micro SD,

- 8 MP camera,

- user replaceable battery,

- "the other half" which is an expansion module (maybe with QWERTY keyboad?),

- Saifish gesture-based  OS,

- android (TM) compatibility

You may preorder here and be part of the movement, like me!:

https://join.jolla.com/en

Happy computing

Nixman

The day has finally arrived!

The much-awaited Sailfish SDK is out in alpha release at https://sailfishos.org/

Currently available for Linux 32 and 64 bit only, but ports to other popular OS's will follow.

Happy computing

Nixman

As of Oracle 11g, the contents of Oracle alert log can be queried directly via a fixed table X$DBGALERTEXT.

desc X$DBGALERTEXT

 ADDR                                               RAW(8)
 INDX                                               NUMBER
 INST_ID                                            NUMBER
 ORIGINATING_TIMESTAMP                              TIMESTAMP(3) WITH TIME ZONE
 NORMALIZED_TIMESTAMP                               TIMESTAMP(3) WITH TIME ZONE
 ORGANIZATION_ID                                    VARCHAR2(64)
 COMPONENT_ID                                       VARCHAR2(64)
 HOST_ID                                            VARCHAR2(64)
 HOST_ADDRESS                                       VARCHAR2(46)
 MESSAGE_TYPE                                       NUMBER
 MESSAGE_LEVEL                                      NUMBER
 MESSAGE_ID                                         VARCHAR2(64)
 MESSAGE_GROUP                                      VARCHAR2(64)
 CLIENT_ID                                          VARCHAR2(64)
 MODULE_ID                                          VARCHAR2(64)
 PROCESS_ID                                         VARCHAR2(32)
 THREAD_ID                                          VARCHAR2(64)
 USER_ID                                            VARCHAR2(64)
 INSTANCE_ID                                        VARCHAR2(64)
 DETAILED_LOCATION                                  VARCHAR2(160)
 PROBLEM_KEY                                        VARCHAR2(64)
 UPSTREAM_COMP_ID                                   VARCHAR2(100)
 DOWNSTREAM_COMP_ID                                 VARCHAR2(100)
 EXECUTION_CONTEXT_ID                               VARCHAR2(100)
 EXECUTION_CONTEXT_SEQUENCE                         NUMBER
 ERROR_INSTANCE_ID                                  NUMBER
 ERROR_INSTANCE_SEQUENCE                            NUMBER
 VERSION                                            NUMBER
 MESSAGE_TEXT                                       VARCHAR2(2048)
 MESSAGE_ARGUMENTS                                  VARCHAR2(128)
 SUPPLEMENTAL_ATTRIBUTES                            VARCHAR2(128)
 SUPPLEMENTAL_DETAILS                               VARCHAR2(128)
 PARTITION                                          NUMBER
 RECORD_ID                                          NUMBER

The PROBLEM_KEY column gives the ORA- error code.

However, being a fixed table, it means that the table is only accessible by SYS, and not viewable in SYS's catalog.

A quick and dirty fix can be to create a V$ public synonym for the view, and grant SELECT to the view to whoever has to access it.

CREATE VIEW SYS.V_$ALERT_LOG
AS SELECT * FROM x$dbgalertext;

CREATE OR REPLACE PUBLIC SYNONYM V$ALERT_LOG FOR SYS.V_$ALERT_LOG;

GRANT SELECT ON SYS.V_$ALERT_LOG TO MYDBUSER;

You can then query the view for interesting details.

For example:

SELECT * FROM V$ALERT_LOG WHERE MESSAGE_LEVEL <> 16 ORDER BY ORIGINATING_TIMESTAMP DESC;

Happy computing

Drop me a line and hang out on the sidebar links if this note has been useful to you.

Nixman

Default PostgreSQL logging is quite discreet.

Supposing you would want to log some SQL statements, and in the same time have a more frequent rotation of your logs, here are the lines to change in you postgresql. conf file:

# Changed from -%a to -%a%H%M
log_filename = 'postgresql-%a%H%M.log'  # log file name pattern,

# Changed from 1d to 60min
log_rotation_age = 60                   # Automatic rotation of logfiles will # happen after that time.  0 disables.

# Changed from 0 to 512k
log_rotation_size = 512                 # Automatic rotation of logfiles will # happen after that much log output. # 0 disables.

# Changed from -1 to 0
log_min_duration_statement = 0          # -1 is disabled, 0 logs all statements # and their durations, > 0 logs only # statements running at least this number # of milliseconds
                                      
# Changed  from none to mod
log_statement = 'mod'                   # none, ddl, mod, all

Beware of the log_statement parameter on overloaded systems, as your log files might experience some pretty heavy I/O.

Leave me a note if this post has been useful.

Happy computing,

Nixman

The guys at Jolla seem to be right on schedule!

This just came in from Jolla's sailfishos.org Q&A page:

When will Sailfish SDK be available?

The version presented at Slush is a technical preview. After presenting it we are applying updates based on the feedback received by the community and we will make the binaries available in early Q1 2013. In the meantime you can follow the steps on the merproject.org page and build most of the SDK yourself.

A few new Sailfish demos from Jolla are out

First the Sailfish SDK demo from Slush:

http://www.youtube.com/watch?feature=player_embedded&v=ZrwYyN-vNVo

Very fast development indeed with this new Qt SDK. Some whiners will of course complain about the lack of an efl SDK...

The second one is in finnish only from Jolla's Senior designer:

http://www.youtube.com/watch?feature=player_embedded&v=NtEbOGuxuig

There are some interesting comments from Jaakko Roppola about the philosophy of the Sailfish UI, that I've tried to translate as accurately possible:

"The UI has been built around simplicity and ease of use"

"No need to into the application and back off. You can just slide the application icon on the side to execute commands"

"What are the limits? - Basically the physical size (of the screen), and in some cases there is no need for interaction. For example the People application doesn't have any interaction"

"What about the multitasking and its limits? - There's a human limit. We don't want to make a second page with icons. When you have a certain number of applications open, the least used one will not be visible. It will still be running, but won't be visible on the home screen" (From what I've heard, it should be 9 application maximum on the home screen currently)

"You can close the application like this (by pressing them a few seconds and tapping the cross)"

"Is there a context menu? - Yes, and we can demonstrate our Ambiance application at the same time. You get the context menu for the application by swiping from top to bottom from anywhere on the screen. When I release it, it executes the function it has been asigned"

"There have been many questions about the Ambiance: is it not just some eye candy? No, it was just one of the targets we wanted to show. You have to think much further than adapting the colours of the phone to some picture you just find in the gallery."

"There is one thing we have been quite clear about when we've been discussing the UI between ourselves: we don't want any buttons everywhere on the screen. Rather, the navigation is by gestures only."

"For example, here , I can go digging very far in the hierarchy, and just swipe my way back to top. But I still see the hierarchy and just by one gesture I can go back to my home screen to check whether I have network, how much battery I've got left..."

"What about notifications? - If you're not using the phone, the notification will be on the home screeen, but if you're using an app, the notification for a call for example will pop up ,but it won't be persistent in the application window. It will be directly on the screen, and you won't have to search for an SMS somewhere in another application. Basically, everything must be very close anywhere, but everything must NOT be everywhere."

Nixman

But:

Oracle Transparent Data Encryption permet de chiffrer et déchiffrer à la volée les données en base. Les données sont chiffrées au niveau des datafiles. Seuls les utilisateurs authentifiés en base ont accès aux données en clair. Principe:

Le chiffrage repose sur l'utilisation d'un portefeuille (wallet) de mot(s) de passe. Contrairement à l'utilisation de packages comme DBMS_CRYPTO, cette solution de cryptage est transparente pour l'utilisateur authentifié, et ne nécessite donc pas de modification du code client, ce qui constitue un avantage financier non négligeable. Il est possible de chiffrer des colonnes spécifiques d'une table, ou bien des tablespaces entiers.

Mise en place:

Création du wallet:

Le wallet est positionné par défaut dans le répertoire $ORA_ADM/$SID/wallet.

Il suffit alors de créer le répertoire:

mkdir $ORA_ADM/$SID/wallet

Il est également possible de spécifier le lieu de stockage du wallet dans le fichier sqlnet.ora, de la façon suivante:

ENCRYPTION_WALLET_LOCATION =
(SOURCE=
(METHOD=file)
(METHOD_DATA=
(DIRECTORY=/u01/app/oracle/MON_REPERTOIRE_A_WALLETS)))

Il faut ensuite créer le mot de passe de chiffrage:

ALTER SYSTEM SET ENCRYPTION KEY AUTHENTICATED BY "M0n#m0T$dE_Pa55E";

Puis ouvrir le wallet sur chacune des instances de la base:

ALTER SYSTEM SET ENCRYPTION WALLET OPEN IDENTIFIED BY "M0n#m0T$dE_Pa55E";

L'ouverture du wallet doit se faire à chaque redémarrage de la base, ainsi que sur l'ensemble des instances d'un RAC.

Cas particulier du wallet sur un RAC:

Le wallet doit être préférentiellement stocké sur un filesystem partagé comme ACFS (ce qui est notre cas). De plus, il faut initialiser les paramètres système et BDD ORACLE_UNQNAME.

ex:

export ORACLE_UNQNAME=MONINST

srvctl setenv database -d MONINST -T "ORACLE_UNQNAME=MONINST"

De même, il faut indiquer le lieu de stockage du wallet en utilisant la variable $ORACLE_UNQNAME dans sqlnet.ora du user oracle, puis redémarrer le listener (avec le user grid).

ENCRYPTION_WALLET_LOCATION =
(SOURCE=
(METHOD=file)
(METHOD_DATA=
(DIRECTORY=/u01/app/oracle/acfsmounts/orabase1/admin/$ORACLE_UNQNAME/wallet/)))

Sinon, le wallet ne peut être ouvert que sur une seule instance à la fois.

Vérification:

select * from gv$encryption_wallet;
INST_ID WRL_TYPE             WRL_PARAMETER                                                          STATUS
---------- -------------------- ---------------------------------------------------------------------- ------------------
1 file                 /u01/app/oracle/acfsmounts/orabase1/admin/$ORACLE_UNQNAME/wallet/      OPEN
2 file                 /u01/app/oracle/acfsmounts/orabase1/admin/$ORACLE_UNQNAME/wallet/      OPEN

Les deux wallets doivent être en état "OPEN"

Chiffrage d'un tablespace:

Le chiffrage d'un tablespace se fait à la création de celui-ci. Il n'est (pour l'instant?) pas possible de chiffrer un tablespace existant.

create tablespace ts_encrypted datafile size 10M autoextend on next 10M encryption using 'AES256' default storage(ENCRYPT);

Il suffit alors de déplacer les données vers ce nouveau tablespace chiffré. L'avantage d'un tablespace chiffré par rapoort au chiffrage de colonnes d'une table est essentiellement dans l'absence de limitations sur l'utilisation des eindexes dans le cas de l'opérateur LIKE, et dans le chiffrage simple des blobs. Le désavantage essentiel est l'impossibilité de l'effectuer en ligne.

Chiffrage d'une colonne d'une table:

On peut chiffrer les colonnes d'une table à l'aide d'une simple commande ALTER TABLE.

ex:

alter table SCOTT.EMPLOYEE modify (ID RAW(32) ENCRYPT);

Dans le cas où la colonne est indexée, il faut désactiver l'option SALT:

ex:

alter table SCOTT.EMPLOYEE modify (DATE_EMBAUCHE DATE ENCRYPT NO SALT);

L'encodage par défaut est AES192 sous Oracle 11gR2.

A noter que les tables ne contenant aucune colonne cryptée seront toujours accessibles, même si le wallet n'est pas ouvert.
Une table contenant une seule colonne chiffrée sera totalement inaccessible si le wallet n'est pas ouvert.

Retour arrière:

Le retour arrière se fait toujours à l'aide d'une simple commande ALTER TABLE.

ex:

alter table SCOTT.EMPLOYEE modify (DATE_EMBAUCHE DECRYPT);

Chiffrage des colonnes LOB d'une table:

Il faut chiffrer les lobsegments en utilisant l'option de stockage SECUREFILE lors de la création du LOB.

Il est possible de chiffrer une colonne LOB en ligne en utilisant le package DBMS_REDIFINITION.

Chiffrage des backups Datapump:

Il est possible d'exporter les données sous forme non chiffrée, avec les options standard de DataPump L'alerte suivante est alors levée dans les logs de l'export:

ORA-39173: Des données cryptées ont été stockées décryptées dans un ensemble de fichiers de vidage.

Dans ce cas, il est toujours possible de lire des données en clair dans le fichier de dump, à l'aide de l'utilitaire strings par exemple.

Afin d'exporter des données chiffrées, il faut ajouter l'option encryption_password à la commande DataPump

ex:

expdp TOTO/TATA directory=EXP_DIR schemas=TITI encryption_password=M0n#m0T$dE_Pa55E dumpfile=dump_titi.dmp logfile=dump_titi.log

De même, il faut spécifier le mot de passe de chiffrage lors de l'import.

ex:

impdp TOTO/TATA directory=EXP_DIR encryption_password=M0n#m0T$dE_Pa55E dumpfile=dump_titi.dmp logfile=impdp_titi.log

Références:

http://docs.oracle.com/cd/E11882_01/server.112/e10575/tdpsg_securing_data.htm#CHDCGGBH
http://www.oracle.com/technetwork/database/focus-areas/security/twp-transparent-data-encryption-bes-130696.pdf
http://docs.oracle.com/cd/B28359_01/network.111/b28530/asotrans.htm
http://docs.oracle.com/cd/B19306_01/network.102/b14268/asotrans.htm
http://docs.oracle.com/cd/B28359_01/appdev.111/b28393/adlob_smart.htm#BABDIEGE
http://oracleflash.com/26/Oracle-10g-Transparent-Data-Encryption-examples.html

Urbicus est un cabinet d'architectes paysagistes basé à Versailles.

Works on: Red Hat 5.3 with Qlogic fiber channel cards

Monitoring failing paths on a fibre channel card connected to a SAN on Linux isn't very straightforward

A handy command to check it in real time would be this one:

watch -n 1 "echo show paths | multipathd -k "

The output would look something like this:

multipathd> hcil    dev  dev_t  pri dm_st   chk_st   next_check

[...]
1:0:3:3 sdam 66:96  50  [failed][faulty] XX........ 4/20
1:0:3:4 sdan 66:112 50  [failed][faulty] XX........ 4/20
0:0:0:0 sda  8:0    50  [active][ready]  XXXXXXXX.. 17/20
0:0:0:1 sdb  8:16   10  [active][ready]  XXXXXXXX.. 17/20
0:0:0:2 sdc  8:32   50  [active][ready]  XXXXXXXX.. 17/20

[...]

Here, controller 1 is failing, resulting in 4 failed paths out of 8.

"4/20" and "17/20" being the number of secons left till the next check

Leave me a note if this post has been useful to you

Happy computing

Nixman

1) Check current controlfile's name and restart the database NOMOUNT

SQL> show parameter control_files

NAME                                 TYPE        VALUE
------------------------------------ ----------- -----------------------------------------------
control_files                        string      +FRA/MYDB/controlfile/current.256.715620719


SQL> shutdown immediate

SQL> startup nomount


2) Copy/restore current controlfile through RMAN

$ rman target /

RMAN> restore controlfile to '+DATA' from '+FRA/MYDB/controlfile/current.256.715620719';

Starting restore at 07-APR-10
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=272 device type=DISK

channel ORA_DISK_1: copied control file copy
Finished restore at 07-APR-10

3) Find out the name of the new controlfile through asmcmd

ASMCMD> ls -lsa +DATA/MYDB/controlfile

Type         Redund  Striped  Time             Sys  Block_Size  Blocks    Bytes     Space  Name
CONTROLFILE  UNPROT  FINE     APR 07 14:00:00  Y         16384     595  9748480  16777216  none => current.283.715704921


4) Modify your spfile to take into account the new controlfile

SQL> alter system set control_files='+DATA/MYDB/controlfiles/current.283.715704921','+FRA/MYDB/controlfile/current.256.715620719' scope=spfile;


5) Restart the database and check

SQL> shutdown immediate

SQL> startup

SQL> show parameter control_files;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
control_files                        string      +DATA/MYDB/controlfiles/cu
                                                 rrent.283.715704921, +FRA/mmtw
                                                 ebdv/controlfile/current.256.7
                                                 15620719



Leave me a line if this note has been useful to you.

Happy computing

Nixman