HOWTO: measure bandwith on AsteriskNOW (SHMZ, CentOS, Fedora)

iptraf allows to measure the throughput on network interface and watch individual connections.You can install iptraf with following command

# yum -y install iptraf

after start it displays as summary traffic as also detailed information about connections for NIC.

# iptraf

Other blogs recommend to install nload or iftop utilities, sadly both are not available in repository and you have to build from sources.

Enjoy!

Asterisk: HOWTO forward DNIS to remote party

Dialed Number Identification Service (DNIS) is a service that lets determine which telephone number was dialed by a customer.

Usually dialed number is known for subscriber, because each DID corresponds unique extension.
It is not a case for transfered calls, because information about DID will be lost. To inform far side about original dialed number the SIP protocol provides the Diversion header.
To set the Diversion field you have to set rdnis variable in dialplan. E.g.

;catch all extension
exten=>_.,n,Set(CALLERID(rdnis)=${EXTEN})

;in the macro
exten=>s,n,Set(CALLERID(rdnis)=${MACRO_EXTEN})

; or hardcoded
exten=>_.,n,Set(CALLERID(rdnis)=123456789)

Enjoy!

Book "LINQ in Action" by Fabrice Marguerie

LINQ, Language INtegrated Query, is a new extension to the Visual Basic and C# programming languages designed to simplify data queries and database interaction. It addreses O/R mapping issues by making query operations like SQL statements part of the programming language. It also offers built-in support for querying in-memory collections like arrays or lists, XML, DataSets, and relational databases. LINQ in Action is a fast-paced, comprehensive tutorial for professional developers. This book explores what can be done with LINQ, shows how it works in an application, and addresses the emerging best practices. It presents the general purpose query facilities offered by LINQ in the upcoming C# 3.0 and VB.NET 9.0 languages. A running example introduces basic LINQ concepts. You'll then learn to query unstructured data using LINQ to XML and relational data with LINQ to SQL. Finally, you'll see how to extend LINQ for custom applications. LINQ in Action will guide you along as you explore this new world of lambda expressions, query operators, and expression trees. As well, you'll explore the new features of C# 3.0, VB.NET 9.0. The book is very practical, anchoring each new idea with running code. Whether you want to use LINQ to query objects, XML documents, or relational databases, you will find all the information you need to get started But LINQ in Action does not stop at the basic code. This book also shows you how LINQ can be used for advanced processing of data, including coverage of LINQ's extensibility, which allows querying more data sources than those supported by default. All code samples are built on a concrete business case. The running example, LinqBooks, is a personal book cataloging system that shows you how to create LINQ applications with Visual Studio 2008 and above.

SoftwareDistribution folder is huge on small drive

Windows cleans SoftwareDistribution directory automatically after updates are installed.
The directory was 1GB big after updates on 20GB partition and the reason was \softwaredistribution\datastore\datastore.edb file.
Forums says just delete the whole folder. Don't do it!
datastore.edb is Extensible Storage Engine (ESE) database and you can shrink it.
Launch cmd.exe as as administrator and execute

net stop wuauserv
esentutl /d %windir%\softwaredistribution\datastore\datastore.edb
net start wuauserv

After defragmentation the file was reduced upto 10MB. Wow! I got free space on the disk.
Enjoy!

Certificate Credentials - Generate Proxy Class

Below you will find my workaround for proxy class generation if remote web service is old-fashioned and protected with certificate credentials.
Often is enough svcutil.exe to generate proxy class. But not in my case because web service was ancient and does not provide MEX, WS or netTcp binding. Please advise whether is possible to use svcutil for archaic service like https://remote.com/service?wsdl
Another way to create proxy class is wsdl.exe utility, but wsdl.exe does not support certificates at all.

Solution: I have installed locally http NGINX revers proxy with following config

    server {
        listen       8080;
        server_name  localhost;

        location / {
     #repace urls in response     
     sub_filter 'https://remote.com:8080/' 'http://$host:8080/';
     sub_filter_types *; # enable all type
     sub_filter_once off;
            proxy_pass https://remote.com:8080/;
            proxy_ssl_certificate  cert.pem;
            proxy_ssl_certificate_key cert.pem;
        }
    }

to convert a PKCS#12 file (.pfx .p12) containing a private key and certificates to PEM file execute

openssl pkcs12 -in keyStore.pfx -out keyStore.pem -nodes

start Nginx and execute wsdl.exe command

wsdl.exe http://localhost:8080/service?wsdl

Enjoy!

How to REALLY destroy stored data

I have written already about SDelete and bootable DiskWipe, but what if you have to rely on the result?
In that case you have only once option - physical destruction!

First you have to disassemble your hard drive disk and extract each single platter.

As next step use blow torch (blowlamp) till surface of disk will be red, look at the photo.

After that all your data are really demolished.

CAUTION! That is truly very dangerous! Fire hazard! 

bulk convert to u-law or a-law audio format

The telephone system requires often audio prompts in u-law or a-law format.
To convert all your wav files you can execute following command in the directory with wav files,
it will convert file and save it with the same file name and new extension

# for a in *.wav; do sox "$a" -t raw -r 8000 -c 1 -e u-law ${a/.wav/.ulaw} ; done

or 

# for a in *.wav; do sox "$a" -t raw -r 8000 -c 1 -e a-law ${a/.wav/.alaw} ; done

Enjoy!