Hello
I am considering getting LNLINUX for a project of mine. I want to automatically retrieve data from a datalogger (which I have yet to obtain), save it as CSV, and store that file in the server (either through a daemon or crontab). I am not clear whether or not LNLINUX has that capability.
Since I am already using a Linux server, it makes sense to get a Linux version. I would prefer not to use Windows if I cannot help it.
Thanks for the help
I think LoggerNet for Linux makes sense for you to use.
When you indicate that you want to "automatically retrieve data from a datalogger, save it as CSV, and store that file in the server", then that is a description of the "scheduled data collection" feature of LoggerNet. LNLinux does this well, and it runs as a daemon on your Linux server.
Configuring the LNLinux server to perform these scheduled collections is much much easier to do if you use the Windows tools (provided with LNLinux) using a remote connection from the Windows machine over to the Linux server.
However, you can use corascript from a command line with the cora_cmd utility to create a datalogger definition and set up an automatic collection schedule. That only needs to be done once, and then the server executes the schedule automatically after that. That can be done on the Linux box without requiring Windows.
So the trade-off applies only to the configuration of the system. If you want it to be friendly and easy, configure remotely with the Windows tools. If you want it to be local on Linux, use corascripts, and you will need to invest some time to learn how those scripts work.
The Task Master is a feature in LoggerNet for Windows that is not included in LNLinux. That is really the only feature that is not available for the Linux version of the product.
More info here:
http://www.campbellsci.com/lnlinux
http://www.campbellsci.com/documents/manuals/loggernet-for-linux.pdf
Also look at the "LoggerNet Packages" section here:
http://www.campbellsci.com/documents/product-brochures/b_loggernet4.pdf
LN Linux will certainly do what you need, even if you avoid using Windows to set it up. However, it is designed and priced to deal with large networks of loggers, i.e. is a little OTT to deal with one logger.
If that is an issue for you, and you have some programming skills, you could either consider our paid for Java SDK, which can be used to develop code on Linux, or if you search this forum, someone has written a Python package which is free and runs on Unix/Linux, but of course that comes with no support from Campbell Scientific.
If you intend to communicate via a TCP/IP connection, there is another option altogether, which is to program the logger to push data on a regular basis via ftp to an ftp server, which could be running on your Linux box.
... Or pull the data by ...
Using the TableFile() instruction to write the data to file and retrieve using FTP or HTTP.
Or
Using the suported HTTP queries to retrieve data in CSV, XML, JSON, etc. (CRBasic Editor Help->Web API)
... Or pull the data by ...
Using the TableFile() instruction to write the data to file and retrieve using FTP or HTTP.
Or
Using the suported HTTP queries to retrieve data in CSV, XML, JSON, etc. (CRBasic Editor Help->Web API)
We've been using LoggerNet-Linux for several years, almost entirely via the corascript interpreter and using the manual-poll
command to retrieve data. Despite the name, manual-poll still automates a lot of internal details, e.g., figuring out how much data is pending, running all the transactions, so is simple to use.
We use the standard /etc/inetd.conf utility to connect to the corascript interpreter, and can run interactively or use something like 'expect' on a client machine to automate sessions. The automated scripts also call on corascript to check and set the logger clock, check and download programs, etc..
We've used the create-backup-script command to obtain a complete list of settings for individual devices, and used that information to 'clone' new devices. I think we may have used a Windows LoggerNet to bootstrap the first devices.
My impression is that some of the alternative solutions, e.g., the PyPak python library, are very capable and worth a look. But LoggerNet-Linux has worked well for us, does what we ask it to do and no more.