Category: architecture

As we are getting more and more acquainted with a valuable flow of free financial information provided generously by a company called Alpha Vantage, we will now come up with a Perl script that would facilitate data extraction from their feed. The abovementioned service is free, but you have to register to obtain your individual API key. For obvious reasons we will use a demo API key in our Perl code examples here. We recommend you to get your own.

There were times when we were looking for simple yet unorthodox solutions; and this case was one of them. Imagine, if there was a Windows 2012 server with its standard VPN service (RAS, or, Remote Access, actually), configured and operational. The only problem was that static IP of the server (as seen by a connected user) was not up at all times. For instance, assume DHCP IP range for VPN clients was 172.0.2.1 – 172.0.2.199. That makes first address of the range, 172.0.2.1 the server’s address that is accessible by VPN clients (inside VPN tunnel). When server just started that IP would be down – not even pingable, let alone not routable. The IP address becomes live as soon as first VPN client is connected from outside to the RAS service. That presented a challenge for application jobs configured to run in both modes: locally on the server and from remote locations connected to the server. We would configure 172.0.2.1 as a universal connection point for all the applications and grant proper server firewall exclusions, though… they would not be able to connect if no external users connected to the VPN service yet.

A detailed how-to recipe of proper configuration of Asterisk for use with RingCentral provider with configuration file samples.

The issue happens because PuTTY user key stored in Windows registry under saved sessions with that server host name takes precedence over the key configured in Tortoise.

We have interviewed creators of CleanTalk, an amazing service that protects thousands of blogs and forums with their very efficient spam-filtering engine.

Amazon AWS instance may become very expensive when running 24/7. Our solution? An automatic shutdown when there is no need to have that server online. This recipe is simple when implemented with AWS’s functionality added not so long ago which was called CloudWatch monitoring.

The main benefit of Windows XP mode on Windows 7 (virtual Windows XP instance under Hyper-V) would be to run legacy DOS applications or other older software that may not be compatible with newer versions of Windows. Also, some of those beasts would not know any better than to print directly to a hardware parallel printer port or LPT. For example, one of that legacy software is FoxPro. The LPT requirement presents a clear challenge since Microsoft did not provide an interface or driver for virtual Windows XP instance to access the host’s printer ports.

A new edition of The Debian Administrator’s Handbook by Raphaël Hertzog, Roland Mas—the third one counting only English editions, and the seventh if the first four French-only are included—has been issued by Freexian. Shortly after the first English edition, communal experience with the book has justified the the in its title, the book becoming both the most widely read introduction into Debian and the most used single handbook, leaving out the documentation itself, of course.

Say, you have a stand-alone Windows 2008 R2 server that is not part of a domain. You decide that it would make more sense to adjust the server name in the system properties (Computer name – Change) from WinServ1 to a more meaningful WinDevelServ1. After mandatory server reboot you discover that (surprise!) Remote Desktop licensing is not active anymore. A brief error message on dashboard icon makes it clear that you have 120 days to activate the license or else users will lose their ability to connect via Remote Desktop.

What went wrong is one of the gotchas of Windows networking. Server name needs adjustments in various places of the system during name change and the Remote Desktop license server setting is apparently one that they forgot to take care of.

We have made a trip to data center recently to replace a faulty 900Gb hard drive in a RAID-10 logical volume of a 3.5 year old HP server. In the modern age of cloud hosting we still manage a few physical servers, for various reasons but mostly for our clients. Since last year we knew the drive may fail due to growing number of soft errors and ordered two extra drives in advance to be ready for day X: one as a replacement and another as a spare for that volume.