Category: Technology

General articles on technology

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Asterisk – “I’m sorry an error has occurred”

I recently experienced an issue with Asterisk 1.8 and the voice mail module. If a voice mail is recorded and is less than 6 seconds a non-descript error message will be played:

“I’m sorry an error has occurred”

The cause is a default 5 second voice mail restriction within Asterisk. The solution is to edit: /etc/asterisk/vm_general.inc and edit the following variables:

; Asterisk post 1.6.2 options the minmessage and maxmessage are deprecated in favor of these
; which are per user settable also:
maxsecs=600                     ; max length of vm message
minsecs=1                       ; Minimum length of a voicemail message in seconds

Save the file then restart the amportal (# amportal restart)

Note that this will set the maximum length of a voice mail to 10 minutes and the minimum length to 1 second.

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Recommended Data Center Temperature & Humidity

Monitoring the environment conditions in a computer room or data center is critical to ensuring uptime and system reliability. A report from the Gartner Group in late 2003 estimated that the average hourly cost of downtime for a computer network at that time was $42,000 (1,260,000 baht). In the year 2011, it has likely gone up dramatically. At these high costs, even companies with 99.9% up-time lose hundreds of thousands of dollars each year in unplanned downtime. Maintaining recommended temperature and humidity levels in the data center can reduce unplanned downtime caused by environment conditions and save companies thousands or even millions of dollars per year.

Recommended Computer Room Temperature

Operating expensive IT computer equipment for extended periods of time at high temperatures greatly reduces reliability, longevity of components and will likely cause unplanned downtime. Maintaining an ambient temperature range of 68° to 75°F (20° to 24°C) is optimal for system reliability. This temperature range provides a safe buffer for equipment to operate in the event of air conditioning or HVAC equipment failure while making it easier to maintain a safe relative humidity level.

It is a generally agreed upon standard in the computer industry that expensive IT equipment should not be operated in a computer room or data center where the ambient room temperature has exceeded 85°F (30°C). Continue reading “Recommended Data Center Temperature & Humidity”

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Windows 7 & Windows 2008 R2 Service Pack 1 Released

Microsoft released Windows 7 Service Pack 1 and Windows 2008 R2 Service Pack 1 to the masses yesterday, February 22nd.

Windows 7 SP1 and Windows Server 2008 R2 is a set of updates and fixes for Windows Server 2008 R2 and Windows 7 that addresses feedback from Microsoft customers (in addition to the improvements that are delivered to users through Windows Update). In addition to including previously released updates, SP1 focuses on specific reliability and performance issues, support for new types of hardware, and support for a few emerging technology standards. Note that although SP1 is not intended to be a vehicle for releasing new features, some existing features do gain enhanced functionality through SP1.

Notable new features include:

RemoteFX – Ever use Remote Desktop to connect to another machine virtually over a LAN? You’ve probably noticed that the experience you get across a network pales in comparison to what you get locally, with features like Windows Aero, full-motion video, and 3D graphics all off limits. RemoteFX will lift those barriers.

Dynamic Memory – According to Microsoft, dynamic memory “allows customers to achieve increased density when they’re consolidating physical servers into a virtual realm, providing them with predictable performance and linear scalability.” Translated: IT administrators can dice up the physical memory on a machine, like a server, and dole it out to many different virtual machines on the fly. Continue reading “Windows 7 & Windows 2008 R2 Service Pack 1 Released”

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OpenDNS is adding a Singapore Datacenter

Good news for those of us in Asia using OpenDNS!

In their October 2010 newsletter, OpenDNS announced that later this year they will adding a new datacenter in Singapore to better serve OpenDNS customers in the Pacific Rim.

Since OpenDNS is anycasted, the new datacenter means faster DNS resolution and an overall faster Internet for OpenDNS users in Asia. If this is where you live, no changes on your end are needed to get the faster DNS resolution — your DNS requests will automatically begin routing through the new servers.

Existing and planned OpenDNS server locations are shown in the OpenDNS network map located here.

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Remove advertisments from Untangle Web Filter

If you are running Untangle’s free “Lite” package,  you may have noticed that advertisements are now shown in the bottom of block pages generated by the Web filter.

Untangle announced that they had put this in place in order to generate revenue to support development of the Untangle platform. Whilst I understand their need to support development, some of the ad’s that show up are of a questionable nature. If Untangle has to show advertisements within its block pages in order to support its back end infrastructure then I fear they may not be around much longer, as a company. I’d suggest Untangle look for sponsors to provide update and download hosting for the open source / Lite applications and only host their commercial applications themselves.

Solutions:

1. Purchase an application from Untangle, for example the Branding Manager which costs $108.00 per year. This will automatically remove ad’s in the Web Filter application and also lets you brand the interface with your own logo etc. This is my recommended method.

2. If your running a test UTM or a small installation at home, you can forcefully remove the advertisements as follows:

a. SSH into your Untangle box.
b. Make a backup copy of the blockpage:

$ cp /usr/share/untangle/web/blockpage/blockpage_template.jspx /usr/share/untangle/web/blockpage/blockpage_template.jspx~

c. Open the block page template: Continue reading “Remove advertisments from Untangle Web Filter”