Are you fascinated with weather? Do you often find yourself checking local weather conditions? Is the weather your favorite part of the news broadcast? If so, you may be a weather geek, and wview may be the application for you.
wview is an open-source weather application that retrieves sensor readings from a weather station. The sensor data is stored in SQLite3 databases. Aggregate data, such as minimums, maximums and averages, are computed and stored in the database back end. Optional uses of the stored data include weather Web site generation; generic file generation for external applications; data submission to third-party organizations, including Citizen Weather Observer Program (CWOP) and Weather Underground; and store-forward to remote data collection centers. A user-friendly HTML interface is provided for configuring your weather station as well as for optional features.
To set up your weather station and publish your data with wview, you need a weather station. Supported stations include Davis Vantage Pro/Pro2 (Figure 1) or Vantage Vue, Texas Weather Instruments, Vaisala WXT510/520, Oregon Scientific WMR9X8 and La Crosse WS-23XX. Next, you need a platform to host the wview application. Desktop computers of any vintage work well, but it often is desirable to host wview on a low-power, unattended system. The now discontinued Linksys NSLU2 has been a popular choice. The new SheevaPlug quickly is gaining popularity as a wview host also. Industrious people even have used a Western Digital Worldbook NAS as their wview host. Because wview is modular and designed for embedded applications, it can be hosted on low-horsepower systems.
Next, you need to install a Linux distribution of your choice. The Debian (and derivatives) wview packages provide the most idiot-proof installation path, but source installs also are straightforward for any Linux distribution.
Finally, you need an interface cable. This may be a simple 9-pin serial cable or perhaps a USB-serial adapter if your host has no serial ports.
To configure wview, open your favorite browser and point it to the wview management Web site, typically http://[your_wview_server]/wviewmgmt/login.php. An HTTP server is required on the wview host (this will be installed automatically if you use the APT packages). Use the default administration password “wview” (you can change this later). After logging in successfully, the System Status page is displayed (Figure 2). The System Status page displays the current state of all wview services as well as other status information.
Configuration is broken up into logical sections with context-sensitive help available by mousing over the configuration items. Click the Station tab to configure the station parameters (Figure 3).
The critical parameters here are the station type and the interface characteristics. Select Save Changes when you are done. Next, click the Services tab (Figure 4).
This page provides the configuration of wview services, log verbosity for the services and e-mail alerts. Services available are File Generation, Alarms, CWOP, HTTP (Weather Underground and Weatherforyou), File Export (SSH or FTP) and Process Monitoring. For now, let's not enable any additional services until you have confirmed your station interface.
Now, let's proceed to the station interface verification. Open a shell on the system that is running wview, so you can follow updates to the system log. At the prompt, enter the following:
$ sudo tail -f /var/log/syslog
This displays new system log messages as they are generated. Here, you will monitor wview startup and status messages. Open another shell, and execute the following:
$ sudo /etc/init.d/wview stop $ sudo /etc/init.d/wview start
You will see a flurry of activity in the system log from the wview processes as they start up. It is a good idea to familiarize yourself with these wview log messages, as a wealth of detail is included that can be very helpful.
Return to the System Status page and observe the status of the station interface and the file generation. If both are not status “green” and “Running”, further investigation in the system log file will be required to find any configuration or station interface issues.
Practical Task Scheduling Deployment
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
Free to Linux Journal readers.View Now!
|The Firebird Project's Firebird Relational Database||Jul 29, 2016|
|Stunnel Security for Oracle||Jul 28, 2016|
|SUSE LLC's SUSE Manager||Jul 21, 2016|
|My +1 Sword of Productivity||Jul 20, 2016|
|Non-Linux FOSS: Caffeine!||Jul 19, 2016|
|Murat Yener and Onur Dundar's Expert Android Studio (Wrox)||Jul 18, 2016|
- Stunnel Security for Oracle
- The Firebird Project's Firebird Relational Database
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- SUSE LLC's SUSE Manager
- Managing Linux Using Puppet
- My +1 Sword of Productivity
- Non-Linux FOSS: Caffeine!
- Doing for User Space What We Did for Kernel Space
- Google's SwiftShader Released
- SuperTuxKart 0.9.2 Released
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide