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 Normally when I install phpmyadmin via "sudo apt-get install phpmyadmin" it is accessible at http://192.168.x.y/phpmyadmin.

Paul

If you have phphmyadmin installed on your pi, you can reach it with the adress http://192.168.x.y/phpmyadmin/.

If it's not installed there is a post explaining how to install it: http://openenergymonitor.org/emon/node/1975

Edit: not the fastest!

HI,

thx for your answers.

Because of this info:

Replaced with https://github.com/emoncms/emoncms/tree/bufferedwrite

I changed the image to "emonSD-13-08-14.img.zip"

There I tried your hints.

First I was not able to get access to the 192.168.x.y/emoncms. Because my intention is to store data locally on the Raspi, i went over so chapter "3a) Recording data locally and/or posting to emoncms.org" I was able to login to the rasp, but the next step (put os-partition to write) failed. ---> "bash: rpi: command not found".

Ignoring this, I tried to enable localemoncms, but there where a lot of error messages about read-only filesystem. Sounds logic.

Why does the rasp not found the command "rpi"?

The command should be

rpi-rw

with no spaces not just rpi, You can find out more about how that command works on this thread http://openenergymonitor.org/emon/node/5567. Although in that instance it turned out to be a stray space.

Paul

you are right.

I always tried "rpi -rw". Its logical for a windows user to make a space between command and parameters. (now I know this is a script)

W/o space it was working :-)

After this i made your "sudo apt-get install phpmyadmin". Oh dear god, the rasp asked me a lot of questions. Hope I answered them correct. Did my very best.. Hehe.

Now I can login as phpmayadmin. You are right, its slow. And what was very astonishing: I am missing the emoncms database.... Do I have to make more modifications? I am comparing all what i see to a normal emoncms-installation. I hope this is not the wrong view.

General: What is my aim: I have an arduino, who is collecting data from S0-counter and temp/hum-sensors. These data-pool is sent from the arduino with api-commands to emoncms. Actually emoncms is running on a w7-server in my home-office. As I have seen a rasp-pi lie around in my studio, i thought it could be an alternative "emoncms-server"

regards/brutzler

Did you re-run the localemoncms-enable command after rpi-rw ?

You can set up 2 (or more) emoncms targets in emonhub so you can continue to collect data on the W7 PC while you asses the PI option. just need to add something like this to the [reporters] section in emonhub.conf in addition to the localhost and/or emoncms.org details

[[emoncms_W7]]

Type = EmonHubEmoncmsReporter

[[[init_settings]]]

[[[runtimesettings]]]

url = http://IP.ADD.OF.W7/emoncms

apikey = xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

>>Did you re-run the localemoncms-enable command after rpi-rw ?

YES!

Big question: For what do i need this "Emonhub". I thought the way for me is:

ARDUINO -> Get http:/blabla telegram like this (http://192.168.x.y/emoncms/input/bulk.json?data=[[0,16,1137]]) to "emoncms-server"  -> emoncms-input -> emoncmsfeed -> dashboard

So its working actually on my W7-server. Never did something with emonhub.

A big question indeed,

I didn't give much thought to your previous W7 set-up and my off the cuff response was based entirely on the fact you are using the RO image which is effectively emonhub with the option of emoncms on a SD card. That doesn't mean you must use it but it is IMO more likely for emonhub to be used without emoncms than the other way round, on a SD card that is. because an SD card is only used on a Pi and more often than not an rfm2pi is used to get data OEM on to a Pi.

emonHub is intended to be a single multi-platform solution to interface input devices to emoncms, hopefully replacing both the php and python raspberry pi to emoncms scripts as well as the "rock solid" OEM gateway previously installed on IPE-R1 raspbian based read-only OS to create the SD card image that this image now replaces.  

If you are happy with the method you are using you can still do it that way, just because emonHub is there it's not compulsory, using emonHub however you could use your existing arduino but change the sketch to send frames in the form nodeid val1 val2 val3 via a socket to port 50011 at IP.ADD.OF.PI and emonhub can add a small amount of extra functionality like buffering if the target server is down and routing to multiple targets as described above, but it is essentially just an interface for sockets serial usb rfm etc with variable decoding and its done in a way to encourage development of custom interfacers and reporters for other inputs and applications.

Theres not much to convince someone to jump ship to emonhub if they are happy with what they have but moving forward it's appeal is it's a common versatile interface for all  most applications therefore unifying how data gets to emoncms so as to focus development .

.....well you did ask :-)

Paul

OK, some more light in the dark.

You want to tell me, that the image with emonhub is not intended for what i want to do, but could work. You think the "older" image "emoncmspiv5avr_2may.img.zip" would be better for my project? BTW: "sudo apt-get install phpmyadmin" is not working on this image :-(

And it will always be a difference between a rasp-pi  to a "normal" computer, because i need a certain package for a pi to minimize read/write on the SD-card. I am afraid, that this will prevent me from using newer emoncms-releases.

I just only thought it would be a low-power-alternative to my w7-server, because always sending data to the server prohibits the computer to go into standby. And that costs energy (money).

Now i have to think about, what is the best solution for me:

• my own "server": (pro: all under my control; contra: energy costs)
• pi: (pro: low energy; contra: ready to use images are not even matching to my need)
• openenergymonitor (or different web-space): (pro: no energy-costs; contra: how do i get access to the mysql database or to the datafiles. Because up to now, i have seen a lot of need for this. Especially to bypass editor problems during setting up feeds and dashboards, or to make backups of dashboards and datafiles)

Edit:

I have seen, there is an emon-py, but there is only talking about serial data-transfer. Looks like, i can not use this for my http-data-transfer? And do i have the same graphic-possibilities like a pc-based emoncms?

My last post wasn't saying the image you are using isn't right. I was giving you an insight to emonhub so you could make your own decision about whether to adopt using emonhub or continue posting direct to emoncms.

I do not recognize that image but by the file name, it doesn't seem recent so possibly not what you want. Most of the recent ready to go images are focused on reducing SD card wear. When RPI was originally used for OEM projects on an SD card the lifespan was seriously reduced due to constant writes. the sd card images have explored and evolved to counter that issue. The 3 major landmarks are the "Rock solid" gateway which was read-only IPR-R1 based forwarding to a LAN or WAN emoncms install, then that was replaced more recently with emonhub running on raspbian configured as read-only and most recently a low-write version of emoncms developed specifically for SD cards was added.

None of this is really relative if you use a HDD with the pi, this is the option that best mimics a "normal" pc, for all intents and purposes aside from it's GPIO and low power it is a small "normal" linux PC when a HDD is used in place of the SD card.

If you want to run a full server version of emoncms on a pi you can do that by plugging in a hdd, moving the filesystem and installing full emoncms in almost exactly the same way you would a linux pc and end up with an installation that works pretty much the same as your W7 install with the additional redis functionality and at a fraction of the running costs.

emonhub is a different decision and if you only want to mimic your existing set-up then you do not NEED it, however there are some benefits and certainly if you plan to add to your network, develop or experiment then emonhub is definitely the way to go,

The current SD image has options to add a hard drive and there is a guide to upgrade to a full version of emoncms, but if you know you want a full hdd install, unless you want to specifically go that route I would recommend installing exactly what you want, how you want rather than using an image optimized for a senario that is not for you.

Sorry for another long post but it's better you have the knowledge to make your own informed decision to avoid straying down another long and winding path to somewhere other than where you want to be :-)

eg the emon-py is another low-write development which is a great concept if you are running on a SD card and do not mind the limitations that imposes.

You have not expressed a need to confine your Pi to an SD card but you have implied you would like full functionality so I think a hdd could be the way to go :-)

Paul

Hi Paul,

no matter about a long posting. I only have to read it certain times to understand exactly what you mean. You think exactly like me. Collecting as much information as possible and then make a final decision.

To your comments:

- emon-py limitations.  I can not see, what limitations there are, only have read, that there is a serial data-input. No idea, if http... datatransfer is possible too.

- hdd on pi: As I know, there is only the possibility to connect the hdd over USB, and because of low power from the pi-usb-ports, an active USB-hub should be used. That makes the whole stuff taking more place. (PI+hdd+HUB+powersupply for hub). Some more questions coming up with this:
- Can i use a SSD instead of a normal (rotating) hdd?
- Do i still need a SD-Card? Don't think  the pi can boot from USB directly
- And my greatest fear: is there a dummy faq to setup the emoncms as you talked above

regards/brutzler

- emon-py limitations.  I can not see, what limitations there are, only have read, that there is a serial data-input. No idea, if http... datatransfer is possible too.

emon-py was the predecessor to the current low write version of emoncms, Trystan was exploring reducing the write stress on the SD card, It is therefore not a full version of emoncms and some features may not be accessible. like maybe the full graphing capabilities of emoncms and possibly histograms etc I'm not entirely sure of the detail, my comment may of been too general and assuming again as it was mainly intended inform you that emon-py is not a full version of emoncms.

- hdd on pi: As I know, there is only the possibility to connect the hdd over USB, and because of low power from the pi-usb-ports, an active USB-hub should be used. That makes the whole stuff taking more place. (PI+hdd+HUB+powersupply for hub).

Yes this is one of the reasons users would prefer to use SD card, it is also the thinking behind the emonPi, I have 2 pi/hdd set-ups one uses a custom lead i made from a 2into1 external hdd lead and a short micro usb extn lead, the pi and hdd are interconnected by usb and powered independently by one 3a power supply. the second Pi has a 1.8" hdd which seems to function perfectly powered solely via the Pi usb.

 - Can i use a SSD instead of a normal (rotating) hdd?

You can but it is the same tech as the SD card so not recommended, the spinning disk is superior here.

- Do i still need a SD-Card? Don't think  the pi can boot from USB directly

Correct the boot partition of the SD card tells the Pi to mount the HDD file system, one of my Pi's boots from an old nokia 64MB SD card, yep that is 64MB, sounds as obsolete as a floppy disc now

- And my greatest fear: is there a dummy faq to setup the emoncms as you talked above

To set up the hdd this is the guide I would recommend http://openenergymonitor.org/emon/node/5092 but at the point where you reboot to hdd do not install using apt-get install emoncms ETC.... as this is not the latest version. at that point use http://emoncms.org/site/docs/installlinux to install emoncms via git. 

Paul

- Can i use a SSD instead of a normal (rotating) hdd?

You can but it is the same tech as the SD card so not recommended, the spinning disk is superior here.

Sure? Why do I have a MSATA-SSD-Drive in my laptop as boot-drive? Always thought SSD are more optimized for frequently R/W-cycles.

But as you tell me a 1,8" HDD is running directly, this would be an option! What sort of USB-Adapter do You use? And is this a special type of 1,8"HDD? I have seen a lot of HDD needing 0,5A and thats to much for the 300mA of the Pi.

Edit:
Perhaps: 5V / 300mA could be enough for 3,3V / 500mA

regards/brutzler

I'm not an expert but general opinion is the SSD will wear prematurely, it has been discussed numerous times try searching the forum for SSD. I think it's easy to confuse fast with frequent,  I think a SSD has a finite number of writes, the technologies vary so some are better than others, a HDD however is spinning anyway regardless of the number of writes.

I thought 500mA was the std USB limit is the Pi different ?

I do have a 1.8" HDD successfully running on a single USB but I am also aware I am pushing the limits of the Pi's USB. I actually bought the 1.8" drive for it's physical size and just thought I would try it on a single USB and it has been fine ever since. I bought it on ebay secondhand in a case so I have not had to use a converter. The case has Hitachi on it but the drive inside is a Toshiba. see pics so I'm unaware of anything special about it.

The HDD states 500mA 3.3v but I imagine that is just for a short time when first spinning up, this will only happen at boot as the disk will then remain in use and does not not park or powerdown. 

I therefore cannot guarantee this method will work, I may of just been lucky with my HDD purchase, I'm not sure.

Paul

I've just bought a Pimoroni PiHub to power my Hitachi HDD, which appears to work well, see this post.

It has a special USB output specifically for the Pi which kicks out up to 1.1A to accommodate any other boards attached to the Pi (which is more than the USB spec) at 5.2V. The HDD is then powered from any the 3 remaining hub ports.
The hub's power supply can supply up to 3A in total, and remains very cool whilst powering my Pi, RFM12Pi, Hub & HDD.

I'm well impressed with it., and even use a spare port to charge my phone.

Paul

Hi Paul,

yes, its a normal 40GB HDD.

How do you supply your pi? over the Micro-USB-plug from your computer (that's atm my way) or with an extra power supply over the blue connector?
I guess you are using a separate power supply ;-)

Hmm...
Sometimes I have seen a power supply wit >1A, plugged into the Micro-USB

brutzler

Hi brutzler

I use the same 5v 3amp micro usb power supply for all my Pi's.

I'm not sure what this blue connector is you refer to, the only blue connector I can see on the Pi is the 3.5mm audio out !

Paul

uppss

forget this. Had a hard night.......

--> I will buy a 1,8" HDD and try to install emoncms like your faqs tell me. May be I need your help again then ....

regards/brutzler