Aquest cap de setmana vaig tornar a donar la meva conferència sobre “SmartHome” en aquesta ocasió vaig introduïr la novetat del sistema de feedback basat en “Tasker + Auto-notification”, a més de l’execusió de tasques basades en “crontab”. També he inclòs un petit avanç sobre el nou projecte en el que estic treballant per tal d’integrar les dades del descalcificador dins del OpenHAB usant una webcam i OpenCV per processar les imatges optingudes.
Agraïr al Xavi, Gerardo i la Laura per haver-me donat aquesta oportunitat. Tant el SCG15 com el SAX2015 són events molt familiars a més l’entorn és espectacular. Tot un descobriment del que malgrat tenir referències no havia pogut disfrutar en primera persona.
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A long time ago there were several free dynamic DNS services but nowadays it's difficult to find one of them. And when you find the service usually you have some important restrictions like: number of updates per day or only few subdomains per account. But in the end I found a good free service of that, it's part of the project guifi.net and is called: Qui; you only need a guifi.net account to use the service and it’s really simple and clear. From my part the compatibility with “ddclient” and the “mikrotik” script are really useful and I want tu highlight this functionality.
I did this conference twice but this time it’s in English as I said before in Catalan, this is how I’m getting real a childhood dream. Thanks to open hardware like Arduino and Raspberry PI and open source software like OpenHab I have a smarthome with several automations. Last Thursday I spoke in “IoT Barcelona meetup” sharing my personal experience automating my house.
If you lost it and you want to watch the presentation video is here:
As simple as that, if you add a new virtual hard drive using VMWare in your virtual machine with Linux and you want to force the re-scan SCSI bus to see the new hard drive when you run, for example: “fdisk -l”. You can force the SCSI bus re-scan with:
# take into account that your new hard drive could be added in different point than "host0"echo "- - -" > /sys/class/scsi_host/host0/scan
El dia 12 de febrer al vespre vaig fer una conferència a la FIB (Facultat d’Informàtica de Barcelona) dins de la UPC (Universitat Politècnica de Catalunya). En aquesta xerra vaig estar explicant com vaig convertint en realitat un somni que vaig tenir quan era petit, estic parlant de domotitzar la casa. Gràcies a enginys com l’Arduino i la Raspberry PI a més d’aplicacions com l’OpenHab podem fer assequible allò que si anem a grans marques comercials es fa caríssim pel meu pressupost.
Next commands are very useful when you don’t have access to the vSphere UI and you have to access to VMWare Hypervisor using SSH or console:
# get the list of virtual machinesvim-cmd vmsvc/getallvms# get the state of a VM with #id: VM_IDvim-cmd vmsvc/power.getstate VM_ID# turn on the virtual machine with #id: VM_IDvim-cmd vmsvc/power.on VM_ID
Another option to turn on the virtual machine using an Ansible playbook:
A long time ago I wrote an entry post about how to set up the SMTP in linux boxes using a relay system you can find the post here: Relay mail from your server without MTA. Remember that SSMTP is not a SMTP service for your system but it’s more than enough for all servers that don’t work as a mail servers. Historically Unix/Linux uses sendmail command to send system notifications but usually this mails are lost because system configurations are not completed. My advice in this sense is use SSMTP.
In the past I used to use SSMTP with a GMail account but security constraints in Google mail services make it difficult to configure today. The new alternative is set up a free Mandrill account as a relay host. Mandrill is a Mailchimp service that allows you to send a lot of emails without problems and there is a free account that allows to send up to 12.000 mails per month free, more than enough usually. If you don’t know how to set up a Mailchimp account the best option to learn how to do it is follow the support documentation it’s very good IMHO.
When you have a lot of linux machines to administer you need something fastly replicable. As you know use Ansible is a very good option. Then I developed a new Ansible role to set up Mandrill accounts to SSMTP services massively using Ansible.
Firstly let me introduce a Windows service called: “Windows Remote Manager” or “WinRM”. This is the Windows feature that allows remote control of Windows machines and many other remote functionalities. In my case I have a Windows 7 laptop with SP1 and PowerShell v3 installed.
Secondly don’t forget that Ansible is developed using Python then a Python library have to manage the WinRM protocol. I’m talking about “pywinrm“. Using this library it’s easy to create simple scripts like that:
In the end it’s time to talk about how to create an Ansible Playbook to deploy anything in a Windows machine. As always the first thing that we need is a hosts file. In the next example there are several ansible variables needed to run Ansible Windows modules on WinRM, all of them are self-explanatory:
[all]10.2.0.42
[all:vars]
ansible_ssh_user=the_username
ansible_ssh_pass=the_password
ansible_ssh_port=5985 #winrm (non-ssl) port
ansible_connection=winrm
The first basic example could be a simple playbook that runs the ‘ipconfig’ command and registers the output in an Ansible variable to be showed later like a debug information:
- name: test raw module hosts: all tasks: - name: run ipconfig raw: ipconfig register: ipconfig - debug: var=ipconfig
As always Ansible have several modules, not only the ‘raw’ module. I committed two examples in my Github account using a module to download URLs and another one that runs Powershell scripts.
My examples are done using Ansible 1.8.2 installed in a Fedora 20. But main problems I’ve found are configuring Windows 7 to accept WinRM connections. Next I attach some references that helped me a lot:
Després d’arribar corrent de Cardiff on era aquest dilluns el dimarts vaig arribar a temps per fer la presentació “Internet of Things low cost” als companys del Tecnocampus de Mataró; per cert, unes intal·lacions brutals res a veure amb la EUPMT on vaig estudiar jo fa una colla d’anys. Jo encara diria més, molt millor que no pas la gran Universitat de Cardiff on vaig ser el dilluns.
Pel que fa a la xerrada agraïr a tothom que hi va assistir, a continuació adjunto les transparències pels que vareu ser-hi i pels que no.
Properament pujaré el video, o la part, del video que es va poder gravar. El problema és que són diversos gigues i he de deixar l’ordinador renderitzant cosa que encara no he pogut fer.
El video no conté tota la presentació però té una part important del contingut, així que desitjo que ús sigui útil:
