Wednesday, November 11, 2009

Clean Sendmail Queue | Ubuntu Linux Howto

Tech Blog - if you need to clear sendmail queue the following is some very usefull commands for doing the job

To check how many pending mail you have use the "mailq -v" command.

Manually removed pending mails
$ rm /var/spool/mail/*.*
$ rm /var/mqueue/*.*

Delete pending mails using sendmail command
$ sendmail -v -q

You can delete certain domain or user or recipient mail using the following command
$ sendmail -qS -v it will delete all mail from *

Delete mail from recipient
$ sendmail -qR -v

You can also use find command to removed queues
$ find /var/spool/mqueue -type f -exec grep "Deferred: Connection refused" {} \; -exec rm -rf {} \;

Hope this help!

Monday, November 09, 2009

Apache SSL and Certificate Authority(CA) | Howto

Tech Blog - Here is a simple howto on creating your own CA or Certificate Authority unders Cent OS 5, this howto would also work on other Linux distribution with modification to path where the command could be found, this howto covers creating a certificate authority using OpenSSL and setting up a secure website using Apache with mod_ssl module.

For Cent OS 5, you will need to have Openssl, Apache with mod_ssl module, and Openssl tools(openssl-perl), you can easily serach for this packages using the yum tool, yum search , make sure that mod_ssl is being Loaded on httpd.conf

Now lets begin with the howto

If you have all the above files installed on Cent OS 5, the path to configuration files below will work for you.

Apache SSL Configuration File - /etc/httpd/conf.d/ssl.conf
Openssl Configuraltion File - /etc/pki/ssl.conf - Openssl Perl Script tools - /etc/pki/tls/misc

Creating a new Certificate Authority

$ ./ -newca
Press Enter to create. - then enter a difficult passphrase do not forget this passphrase
Fill in your details and provide a sensible name for the
Common Name (eg, YOUR name) []:

This creates a new CA certificate in the directory /etc/pki/CA. The CA's self-signed certificate is stored in /etc/pki/CA/cacert.pem and its private key is in /etc/pki/CA/private/cakey.pem. make sure to secure this files.

Certificate Request

Now you need a server certificate that is signed by your own CA. First, generate a certificate request. Fill in the details and make sure "Common Name" is the hostname of the website.
$ ./ -newreq Produce a passphrase for the server certificate. Common Name (eg, name) []:

The certificate request are in newreq.pem.

Now sign the request as the root CA,

$ ./ -sign Enter the passphrase for the root CA. Enter the passphrase for the server certificate.

The server certificate is placed in newcert.pem. The private key is saved in newkey.pem.

Make sure the private key is never world readable. Secure the PEM files including newreq.pem for later use and make sure they are kept private..
$ chmod 0400 newkey.pem

Adding Certificate to your Apache ssl.conf

Look for the following lines under /etc/httpd/conf.d/ssl.conf

SSLCertificateFile /pathto/newcert.pem
SSLCertificateKeyFile /pathto/newkey.pem
SSLCACertificateFile /pathto/cacert.pem

Make sure to Uncomment the following lines as well

SSLVerifyClient require
SSLVerifyDepth 10

Then restart Apache /etc/init.d/httpd restart it will ask you to enter the passphrase you use for the CA

Creating Client Certificate

You can recreate a newreq.pem and newkey.pem, or just use the ones you have generated before, now we will combine newreq.pem and newkey.pem and convert them into the PKCS#12 format that can be imported to our browser..

$ cat newcert.pem newkey.pem >> signing.pem $ openssl pkcs12 -in signing.pem -out signing.p12 -clcerts -keysig -export

Enter the Passphrase then Enter a password for export. When importing the the p12 file to your browser you will be asked for it again.

Now you should see a file named signing.p12, download it to your desktop then import it to your browser, then thats it.

If you wanted to generate ceritificate for a lot of individual or make a script of it you can use

$ openssl pkcs12 -passin pass:yourpassphrase -in signing.pem -passout pass:yourexportpassword -out signing.p12 -clcerts -keysig -export

Below are some howto on troubleshooting

Sunday, November 08, 2009

Magellan Roadmate 300 GPS System

Tech Blog - Magellan is fast becoming a leader in the market of providing navigation solutions. They do marketing for GPS solutions in different areas like automotive markets, consumer electronics and recreation. They have recently introduced a GPS device of model name Magellan Roadmate 300 GPS System with diversified features.

It is a hand held device with weight of about 0.3Kg and dimension 15.7cm (L), 3cm (D) and 7.9cm (H). The boxed-product weight of this device is 1.4 Kg. It comes with 14 channel receiver system and is easily portable into a car. Different maps are included for the countries like Great Britain, Europe, Western France and Ireland in this device. Together with a built-in TFT colour touch screen display of size 3.5”, this model GPS comes with a built-in antenna too. It is easily visible during day time. This GPS does not come with an internal battery. If a user loses the signal then he can get guidance easily from a list of directions that will be displayed on the screen so that the user can know where he is exactly. It comes with 320x240 QVGA and 32000 colours along with vehicle power cable. Magellan Roadmate 300 portable GPS System comes with internal memory and an expansion slot type of Secure Digital Card Slot. The accessories that is included while buying this machine are Vehicle power cable, USB Computer cable, car power adapter and Quick Start guide.

Magellan Roadmate 300 Satellite Navigation System comes with different routes like Shortest, Least Use of Freeways, Most Use of Freeways and Avoid Toll Roads that can be selected accordingly. It comes with an advanced feature where multiple users can store their address books and favourites. Magellan Roadmate 300 GPS comes with navigation pad and a set of zoom buttons. If you get lost in a crowd or a jungle accidentally, then the locate button tells where you are exactly and thus you can move on to the correct location. The user interfaces of this machine are touch screen and keypad.

Compare Sat Nav prices and offers at Acer, Garmin, Blaupunkt, Fujitsu-Siemens and TomTom Sat Navs at Satellite Navigation Systems website.

Thursday, November 05, 2009

Panasonic UF8100 fax machine

Tech Blog - Established in 1972, Panasonic is becoming a leading supplier of consumer and business related electronic products. Its parent company Matsushita Electric Industrial Co. Ltd. also has a number of manufacturing plants in UK. Among other electronic equipments, it manufactures fax machines that are widely used in busy offices all over the world.

It supports plain paper laser monochrome technology. Recently Panasonic has introduced a new model fax machine UF8100 which has diversified features that makes it the most remarkable one in the industry. Now don’t worry about the mess caused while working with your old styled fax machine. Just go through the features and specifications of this model given below to know more about it.

Panasonic UF8100 plain paper fax machine is capable of supporting documents ranging from big to small. It has the most important feature called automatic document feeding. It supports a fast 1.5 second quick scan and is called in different names like Panasonic UF8 100, Panasonic UF8100, Panasonic UF 8100, UF8 100, UF8100, and UF 8100. It shares documents digitally and increases the working capacity. This machine has the dimension of Width 45 cm, Depth 41.8 cm, Height 44.8 cm and weight of 22 kg. It has the plain paper fax operation with the capability of printing in 256 shades of Grey, which gives extra depth and clarity to both text and images. This model fax machine has 256 grey scale half-tones and supports a maximum of 99 copies. It also has automatic duplexing. It comes with Error Correction Mode (ECM) with 80 station(s) One Touch Dialling and 200 station(s) Speed Dialling. It also has 330 stations Broadcast Transmission and built-in Delayed Transmission. Remote Fax Retrieval (Polling) is Built-in with Fax forwarding features. Panasonic UF8100 plain paper fax machine has one year warranty.

The maximum transmission speed of Panasonic UF8100 laser fax machine is 33.6 Kbps, maximum printing speed is up to 18 ppm (A4) and scanning speed is up to 50 ppm (A4).

It owns the maximum Printing Resolution of up to 1200 x 600 dpi and Optical scanning Resolution of 600 x 600 dpi.

Memory capacity
This machine has the memory capacity of up to 720 pages and Maximum Media Capacity of 800 sheets. The Supported Media Type is Envelopes and plain paper and has 250 sheets of Standard Media Capacity.

Paper load capacity
Panasonic UF8100 Multifunction Fax Machine has the Document feeder capacity of 100 sheets and Bypass tray capacity of 1 sheet. The Input tray paper load capacity is 250 sheets and that of ADF paper load capacity is 100 sheets.

Operating System Support
It is compatible to different Operating Systems like MS Windows XP, MS Windows 2000, MS Windows NT 4.0, MS Windows ME, MS Windows 98 and MS Windows Server 2003.
You can checkout latest fax machine prices and offers from Brother, BT, Canon and Oki Fax Machines at UK Fax Machines Site.

Tuesday, November 03, 2009

Sonos ZP100 Zoneplayer HiFi System

Tech Blog - Sonos is a well known company manufacturing music systems for music lovers. Among several other models manufactured they have recently come up with the latest model in music system, Sonos ZP100 Zoneplayer HiFi System.

Sonos ZP100 Zoneplayer HiFi System is available with stereo sound system having the facility of playing and amplifying the digital music and Internet radio. Connection to the music system can be either wired or wireless. The amplifier has the output power of 50 watt. This model hifi system supports CD player and MP3 player along with speakers included and separate sub-woofer. It supports streaming MP3 format. It comes with bass control audio system with network audio player function.

Different radio services supported by this music system are SIRIUS Internet Radio and Pandora. Operating systems compatible for stored files are Windows XP SP2 or higher, Windows Vista; Mac OS X v10.4 and v10.5 NAS. Voltage required to run this music system is AC 120/230 V (50/60 Hz). Its built-in amplifier brings music to every corner of the room. It is available in light grey matte aluminium colour. It comes with the dimension of 26cm (W) x18.4cm (D) x11.3cm (H) and weighs about 4.5 Kg.

Wireless ZonePlayer connection is possible when wired Ethernet connection is not available. Speakers can be amplified with 50Watts per channel. Sonos ZP100 Zoneplayer Hi-Fi System comes with power output of AC 120/230 V (50/60 Hz). To access Internet radio station, internet connection is necessary. Ethernet port may be used to connect to PCs, routers and more ZonePlayers. It supports music stored in different media like PCs, NAS or Macs, legacy A/V devices and Internet radio. It supports compressed WMA, MP3, Ogg Vorbis, Flac music files, AAC, uncompressed AIFF and WAV files. Different sound controls can be set for different zones. Sonos ZP100 Zoneplayer HiFi Stereo System fits in small spaces easily.

You can find cheap mini and micro hi-fi systems from Akai, Alba, Elta, Philips, Sharp and Yamada Hi-Fi Systems at Hi-Fi Systems Website.

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