18 mag 12 The OrientDB 1.0 stable is finally there!
Congratulation to Luca Garulli and his dev team to the public release of OrientDB 1.0 Stable!
After a year of release candidates and bug fixing it’s finally time to the stable version.
Many may bugs fixed, new indexing algorithms, improved clustering with multi master replication, new Object Database interface with lazy object loading, new studio (web interface) and much more.
The community is growing fast and people get rapidly moving to new technologies.
Words like nosql, object and graph databases, cloud and mobile are big buzzwords of nowadays.
If you didn’t already, subscribe to the orientdb mailinglist to get in touch: http://groups.google.com/group/orient-database?pli=1.
20 apr 12 Avaaz urgent petitions to sign NOW and quickly!
Urgent Online Petitions to sign now and quicky!! Please wide spread!!
https://secure.avaaz.org/it/monti_save_our_internet/
In qualità di cittadini preoccupati, le chiediamo di fermare immediatamente tutte le iniziative del governo volte a dare all’Autorità per le Garanzie nelle Comunicazioni (AGCOM) il potere di censurare siti internet senza mandato del giudice. Le chiediamo inoltre di riaffermare pubblicamente che solo il Parlamento può approvare leggi che incidono sui nostri diritti fondamentali, inclusa la libertà di espressione, come affermato dalla Costituzione. Ci affidiamo a lei per proteggere la libertà di Internet in quanto pilastro fondamentale della nostra democrazia.
https://secure.avaaz.org/en/stop_cispa/
As concerned global citizens, we urge you to immediately drop the Cyber Intelligence Sharing and Protection Act (CISPA). Our democracy and civil liberties are under threat from the excessive and unnecessary Internet surveillance powers it grants. The Internet is a crucial tool for people around the world to exchange ideas and work collectively to build the world we all want. We urge you to show true global leadership and do all you can to protect our Internet freedom.
08 mar 12 How to execute a HTTP/Rest Query to NuvolaBase distributed database with PHP
As previously said, nuvolabase.com is a great service that permits you to have a distributed nosql document database in the cloud. This is very cool: think each time you would had the need of a database always available in the cloud that you would access via simple HTTP/Rest queries. The possibilities are endless.
Here is a very simple but powerful PHP curl agent to submit commands (queries) to nuvolabase via HTTP.
<?php
/*
* Author: Dino Ciuffetti <dino@tuxweb.it>
* Object: Execute a remote query to a distributed database on nuvolabase.com (free account) using HTTP (OrientDB REST API)
*/
/* user configurable parameters */
$nuvolabasedb = ‘db$free$youruser$yourdb’;
$command = ‘select from yourclass’;
$user = ‘admin’;
$password = ‘qwerty’;
$useragent = “NuvolaBase PHP REST agent/v0.8 (compatible; Mozilla 4.0; MSIE 5.5; http://www.nuvolabase.com/)”;
/* END of user configurable parameters */
$nuvolabasehost = ‘studio.nuvolabase.com’;
$url = ‘http://’.$user.’:’.$password.’@’.’studio.nuvolabase.com/command/’.$nuvolabasedb.’/sql/’;
$ch = curl_init();
// set user agent
curl_setopt($ch, CURLOPT_USERAGENT, $useragent);
// return the result or false in case of errors
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
// set the target url
curl_setopt($ch, CURLOPT_URL, $url);
// do basic login authentication
curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
// howmany parameter to post
curl_setopt($ch, CURLOPT_POST, 1);
// the post data to send
curl_setopt($ch, CURLOPT_POSTFIELDS, $command);
// execute curl,fetch the result and close curl connection
$res = curl_exec ($ch);
curl_close ($ch);
// display result
if ($res !== FALSE);
print_r (json_decode($res));
?>
21 feb 12 Mitigare attacchi di tipo Distributed Denial Of Service su apache con mod_evasive
Ciao.
C’e’ un modulo molto carino non official per apache che permette di bloccare o comunque mitigare facilmente attacchi di tipo DDOS.
Si scarica il modulo mod_evasive dal sito http://www.zdziarski.com/blog/?page_id=442, si decomprime il tar.gz e si compila con la seguente stringa:
<directory_di_installazione_apache>/bin/apxs -i -c mod_evasive20.c
Ora bisogna inserire due cosette in httpd.conf e successivamente riavviare gli apache:
1) LoadModule evasive20_module modules/mod_evasive20.so
2) La sua configurazione
Per quanto riguarda la numero 2 bisogna fare una considerazione importante, ovvero che il tuning del presente modulo con parametri errati o maldimensionati puo’ provocare dei falsi positivi che creano gravi disservizi per un periodo anche prolungato di tempo.
La configurazione e’ simile a questa (effettuo già un pre tuning che comunque dovrete ricontrollare e confermare voi che conoscete il vostro sistema):
<IfModule mod_evasive20.c>
DOSHashTableSize 196613
DOSLogDir “/tmp”
DOSPageCount 20
DOSPageInterval 10
DOSSiteCount 350
DOSSiteInterval 5
DOSBlockingPeriod 10
</IfModule>
Di seguito una breve spiegazione dei parametri:
DOSHashTableSize: e’ la dimensione della tabella di lookup interna usata dal modulo. Su server carichi il numero non deve essere troppo basso. Non andrebbe messo un numero casuale ma un numero primo presente nella struct dei numeri primi dentro mod_evasive20.c.
DOSLogDir: e’ una directory dove evasive appoggia dei dati che vengono utilizzati internamente per motivi di locking tra i processi child di apache
DOSPageCount: e’ la soglia per il numero di richieste effettuate verso una stessa url da uno stesso IP entro un determinato intervallo di tempo specificato dalla direttiva DOSPageInterval. Se il numero di richieste verso una stessa pagina/oggetto/uri viene superato nell’intervallo di tempo specificato apache blocchera’ l’IP del client per un determinato numero di secondi specificati dalla variabile DOSBlockingPeriod. Consiglio vivamente di non impostare questo parametro troppo basso per evitare falsi positivi all’interno di ambienti nattati o dietro proxy server (ad esempio clienti fastweb, utenti all’interno di grosse organizzazioni che usano un proxy server, ecc.)
DOSPageInterval: e’ l’intervallo di tempo espresso in secondi che attiva la soglia relativa al parametro precedente (DOSPageCount)
DOSSiteCount: e’ la soglia per il numero di richieste complessive verso tutto il sito effettuate da uno stesso IP entro un determinato intervallo di tempo specificato dalla direttiva DOSSiteInterval. Se il numero complessivo di richieste verso apache viene superato nell’intervallo di tempo specificato, apache blocchera’ l’IP del client per un determinato numero di secondi specificati dalla variabile DOSBlockingPeriod. Anche qui consiglio vivamente di non impostare questo parametro troppo basso per evitare falsi positivi all’interno di ambienti nattati o dietro proxy server (ad esempio clienti fastweb, utenti all’interno di grosse organizzazioni che usano un proxy server, ecc.)
DOSSiteInterval: e’ l’intervallo di tempo espresso in secondi che attiva la soglia relativa al parametro precedente (DOSSiteCount)
DOSBlockingPeriod: e’ l’intervallo di tempo espresso in secondi durante i quali tutti i client finiti in blacklist avendo superato i limiti imposti dai parametri specificati sopra non potranno collegarsi ad apache e navigare sul sito ottenendo invece un codice di errore HTTP/403 (Forbidden). Se i clients bloccati continuano ad effettuare nuove richieste durante il periodo di blocco, ogni richiesta resetta il timer percui il conteggio ricomincia. Consiglio quindi VIVAMENTE di non impostare questo parametro troppo alto, in genere non vanno mai superati i 20 secondi. Il motivo principale e’ la mitigazione di eventuali disservizi causati da falsi positivi. Il discorso e’ inoltre valido perche’ durante un attacco DDOS il timer viene continuamente resettato e l’attacco viene comunque mitigato anche impostando il parametro ad un valore molto basso.
Riavviate apache e buon divertimento.
Dino Ciuffetti.
02 feb 12 NuvolaBase: the new no-sql company behind OrientDB launches the Graph Database in the Cloud
London, UK – NuvolaBase Ltd is a London-based startup that is about to revolutionize the database market. Only two years ago this market was dominated by few big players such as Oracle, IBM and Microsoft. Something, in the last 24 months, has changed thanks to the “NoSQL” movement which focused on alternative solutions to the ordinary Relational DBMS’s due to the pressing and increasing demands for better performance and higher scalability.
Today the largest IT companies avail themselves of NoSQL solutions to manage Mission Critical projects. Google, Amazon, Microsoft, Facebook, Twitter, Disney, MTV, Craiglist and FourSquare are amongst the most famous ones.
After just a year of testing, NuvolaBase comes out of Alpha version, offering a NoSQL database of high performance as a cloud-based service. This way the database is no longer a software component that needs installing, configuring and maintaining, but it becomes a distributed service that is always available on the internet.
Web Site: http://www.nuvolabase.com
Follow us on Twitter: https://twitter.com/#!/nuvolabase
LinkedIn: http://www.linkedin.com/company/nuvolabase-ltd
26 gen 12 liborient, OrientDB C library migrated to github
I never said before on those pages that some months ago I migrated liborient to github: liborient project page.
For those who do not know liborient, it’s a LGPLv3 library that can be used by C programs to interact with the OrientDB DBMS Server using the orientdb binary protocol. At the time of this writing it’s in development stage, but almost all low level binary protocol methods are implemented and should be quite working.
After fixing some (well known) memory leaks on the new odocument interface, I’m now working on a high level API that can be used by C programs to manipulate objects going to and coming from OrientDB Server.
You can, for example, put or get records to/from the server containing different data type fields. Those fields are organized into an object that OrientDB calls Document. This Document can include structured types like: integers, shorts, dates, strings, binary, char, float, collections, maps, documents embedded into documents, and more.
The liborient’s new odocument higher level API should make you comfortable to access and manipulate this documents.
This can be, for example, a good starting point to create native bindings for other languages like PHP, python, perl, ruby, etc.
At the moment I am the author and the only developer on this project, but if you are brave you can join and submit patches, test the code, open bugs, put your considerations, and so on. Feel free to send me a mail, add a comment to this page, write to the orientdb mailing list, send me a tweet at @tuxweb, or anything else.
15 nov 11 How to compile apache httpd on HP-UX 11.11 PA-RISC
The first thing that I have to say, after more than 10 years working with different OSes, is that there is no better operative system than Linux. Any other OS that I’ve worked with is a pure shit, in my humble opinion off course. HP-UX is one of this. This is a closed box with custom patches here and there, not a true, modern os like linux or free bsd, and the like. The compiler is closed source and it’s not free.
The best way that I’ve found to compile apache with gcc on HP-UX 11.11 (pa-risc) using open source free software is:
- download the following software packages from HP-UX Porting Centre (http://hpux.connect.org.uk/) – your version may vary: zlib-1.2.5-hppa-11.11.depot.gz, make-3.82-hppa-11.11.depot.gz, libiconv-1.14-hppa-11.11.depot.gz, gettext-0.18.1.1-hppa-11.11.depot.gz, openssl-1.0.0e-hppa-11.11.depot.gz, libgcc-4.2.3-hppa-11.11.depot.gz, gcc-4.2.3-hppa-11.11.depot.gz
- gunzip each one of the downloaded depot, (eg: gunzip * from the directory where you downloaded)
- install each depot in the order given below (the first is zlib, the last is gcc) with the standard hpux command: swinstall -s [your_absolute_depot_path]
- once this boring operation mandatory only on non modern operative systems is terinated successfully, you can export the PATH variable setting /usr/local/bin in front of the PATH list: export PATH=”/usr/local/bin:$PATH”
- ok. We are now ready to compile apache. Download and uncompress the httpd tar.gz with “gunzip”, then “tar xf” (on a modern system you can do it in a single pass with tar xzvf …)
- the configure string to run is: ./configure –with-included-apr –with-expat=builtin –prefix=[YOUR_APACHE_INSTALLATION_PATH] –enable-mods-shared=most –enable-ssl –enable-proxy –enable-proxy-connect –enable-proxy-http –enable-proxy-balancer –enable-cache –enable-disk-cache –enable-mem-cache
- once finisced, run: “gmake“.
At this point, after some minute, you probably will end with a compiler error like this one:
/var/adm/crash/src/httpd-2.2.21/srclib/apr/libtool –silent –mode=link gcc -g -O2 -pthread -L/usr/local/lib -o htpasswd htpasswd.lo -lm /var/adm/crash/src/httpd-2.2.21/srclib/pcre/libpcre.la /var/adm/crash/src/httpd-2.2.21/srclib/apr-util/libaprutil-1.la /var/adm/crash/src/httpd-2.2.21/srclib/apr-util/xml/expat/libexpat.la -liconv /var/adm/crash/src/httpd-2.2.21/srclib/apr/libapr-1.la -lrt -lm -lpthread -ldld
libtool: link: warning: this platform does not like uninstalled shared libraries
libtool: link: `htpasswd’ will be relinked during installation
/usr/ccs/bin/ld: Unsatisfied symbols:
apr_generate_random_bytes (first referenced in .libs/htpasswd.o) (code)
collect2: ld returned 1 exit status
gmake[2]: *** [htpasswd] Error 1
gmake[2]: Leaving directory `/var/adm/crash/src/httpd-2.2.21/support’
gmake[1]: *** [all-recursive] Error 1
gmake[1]: Leaving directory `/var/adm/crash/src/httpd-2.2.21/support’
gmake: *** [all-recursive] Error 1
This means that the APR library cannot generate random numbers. I have to investigate why, probably the system is not capable/patched to generate PRN numbers at kernel level (/dev/random or /dev/urandom) and the APR library breaks. Not a problem. Simply skip the creation of the htpasswd executable. You will probably not need it.
- cd support
- touch htpasswd
- cd ..
Now came back to compile:
- gmake
when finished, simple “gmake install“, and you hopefully have done, thinking why you are still using a non modern os and becoming soon a happy new linux user..
Hope this one will help some linux user fighting on HP as well like me!
Ciao, Dino.
12 ott 11 NuvolaBase project – Thu 20th I’ll be in London
On Thu 20th, I’ll fly to London City, I have to accomplish a interesting task for the NuvolaBase project.
News will come.
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28 ott 11 Commenti moderati per default causa spammers
A causa dei soliti spammers maledetti (che Dio li fulmini quando cliccano su “invia”), ho dovuto abilitare la moderazione forzata dei commenti nel blog.
Ora siete contenti vero?
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