Category Archives: System

Build your own NAS/HTPC from scratch – part 1

A NAS/HTPC ?

In this article I’ll walk you through building your own NAS/HTPC, from hardware to software. Since it should be quite long, it should be broken down in several parts.

Let’s see first what I want as a NAS/HTPC, how much would it cost, what was chosen !

Wish list

Here goes my wish list:

  • Store a lot of data (movies, series, musics, ebooks, backups, …)
  • Store some data safely (at least RAID 1) such as family data (pictures, videos)
  • Export that data to different devices (Android tablet, other computers, …), for example ebooks
  • Watch all of the movies, series easily in HD on the NAS/HTPC but also on others devices within my LAN
  • Control most of it from WEB GUI and/or Android applications
  • Be cheap, in comparison to turnkey solutions
  • Low consumption / Low noise

Choices made

I’ve tried out several solutions, if I had been brighter, perhaps I would have listed the solutions and their drawbacks, but well I didn’t think about publishing an article. Let’s go through both hardware and software solutions, these are my choices, don’t follow blindly do your researches according to your wish list.

Hardware

On the hardware side, choices were clearly ruled by the price, I’ve tried to reduce the cost as much as possible without having to give up on quality.

  • Motherboard: ASUSTeK Computer INC. P5K-E I got it for free from a friend. It’s enough for my needs.
  • CPU: Intel(R) Core(TM)2 Duo CPU E8400 @ 3.00GHz, free too it really costs nothing nowdays.
  • CPU FAN: Noctua NH-U9B SE2 (~50€)
  • RAM: 4GB DDR2 800MHZ, also free, it’s consuming right now 1.3GB
  • DISKS: 4TB SATA3 WG40EZRZ (~ 80€ on special sales) // 500GB HITACHI // 500GB TOSHIBA, both I had bought years before
  • CASE: Cooler Master N300 (KKN1) (~50€)
  • FANS: 2 x 120mm front Noctua NF-S12B redux (~30€)+ 1 x 120mm side + Rheobus Lian Li PT-FN01 (10€)
  • GPU: GeForce GT 630, I got it back from an old computer, you’ll see in the hardware part how I fixed its well known noise problem, bit hackish. It doesn’t cost much and can do 1080p HD.
  • POWER SUPPLY: LDLC QS-460 FLP Quality Select 80PLUS Platinum (~50€ on special sales)
  • EXTRAS: anti noise screws for hard drive (~10€), HDMI cables, ethernet cables …

The overall cost is ~300€. So yes most of the hardware is old but my main goal is only to do a decent NAS/HTPC without putting much money on it. Conclusion is that it’s cheaper than turnkey solutions and is more flexible. I can go up to seven hard drives with my current case (6 only with my motherboard but well PCI SATA exists), 8GB RAM (or more), the GPU is decent enough for my needs. I strongly recommand to reuse components from older computers as I did, not only to save the bill but also the environment.

Software

As the base OS, openmediavault is my choice, it’s the perfect “NAS software” solution to me, it’s easy to use/install and quite light. You can manage your disks, RAID arrays, shares without effort (WEB GUI but also SSH hopefully). There are also plugins like Let’s Encrypt or Domoticz that come handy. It has no x server but we will see how to configure one with nodm.

For the HTPC part, kodi is clearly the right choice. An entire article is dedicated to kodi so I won’t say much about it now, but you’ll be able to start a video on your HTPC and continue it on your tablet at the timestamp you stopped, theming, control from your Android devices with Yatse.

Everyone downloads; so after many tests with several torrent clients, rtorrent is my choice ! What weight in the balance is the fact that you can use a WEB GUI, Deluge too, but that last one caused me many problems.

No cost at all except a long amount of time, but these articles should save you some time.

What’s next ?

In the next articles I’ll show you how the hardware takes place, it won’t be a step by step tutorial but it will show you the final product.

Duplicity to backup safely your data

A good backup tool ? Duplicity

I’ve tried many tools to backup, from bare rsync to tools such as restic or borg. Although they’re all good solutions, my requirements were never fully met. It’s why I chose to test and use duplicity. In this post I’ll focus on full server backup.

Here are my requirements for a good backup tool:

  • compression: I don’t have much to backup but I don’t want to use much either.
  • encryption: I only have a basic FTP that I don’t own, there it’s using GnuPG.
  • incremental backup: Also to save disk space.
  • on a FTP: with restic or borg directly I had lock problems over a curlftpfs mount, any backup would fail, it’s not related to these tools but to my usage.
  • easy to use and restore, it keeps ownership and rights.

Install duplicity

It’s pretty straightforward, install the duplicity package through your package manager on your server. You may also install ncftp if you want to backup over FTP.

# apt-get install duplicity ncftp
Install duplicity and ncftp

Generate your keys

Let’s generate your GNuPG key pair so we can encrypt our backup. This time, on your own computer, and not on your server, do the following.

# gpg --gen-key
Generate your GnuPG key pair

Take a 4096 bits length key, most of the default values should be enough.

# gpg --gen-key
gpg (GnuPG) 1.4.20; Copyright (C) 2015 Free Software Foundation, Inc.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

gpg: keyring `/home/floreo/.gnupg/secring.gpg' created
gpg: keyring `/home/floreo/.gnupg/pubring.gpg' created
Please select what kind of key you want:
   (1) RSA and RSA (default)
   (2) DSA and Elgamal
   (3) DSA (sign only)
   (4) RSA (sign only)
Your selection? 
RSA keys may be between 1024 and 4096 bits long.
What keysize do you want? (2048) 4096
Requested keysize is 4096 bits
Please specify how long the key should be valid.
         0 = key does not expire
      <n>  = key expires in n days
      <n>w = key expires in n weeks
      <n>m = key expires in n months
      <n>y = key expires in n years
Key is valid for? (0) 
Key does not expire at all
Is this correct? (y/N) y

You need a user ID to identify your key; the software constructs the user ID
from the Real Name, Comment and Email Address in this form:
    "Heinrich Heine (Der Dichter) <heinrichh@duesseldorf.de>"

Real name: Floreo Backup
Email address: xxx@floreo.info
Comment: Floreo Backup
You selected this USER-ID:
    "Floreo Backup (Floreo Backup) <xxx@floreo.info>"

Change (N)ame, (C)omment, (E)mail or (O)kay/(Q)uit? o
You need a Passphrase to protect your secret key.

We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
........+++++
.............+++++
We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
.+++++
.......+++++
gpg: /home/floreo/.gnupg/trustdb.gpg: trustdb created
gpg: key 1A6F2256 marked as ultimately trusted
public and secret key created and signed.

gpg: checking the trustdb
gpg: 3 marginal(s) needed, 1 complete(s) needed, PGP trust model
gpg: depth: 0  valid:   1  signed:   0  trust: 0-, 0q, 0n, 0m, 0f, 1u
pub   4096R/1A6F2256 2017-11-11
      Key fingerprint = CC2D 8FF5 9BB2 8D88 0E30  0056 FC84 663E 1A6F 2256
uid                  Floreo Backup (Floreo Backup) <xxx@floreo.info>
sub   4096R/874F94F5 2017-11-11
Generate your GNuPG key pair

Now export both the private and public keys, the first one you will keep it safely on a USB drive or anywhere safe, it would be used to decrypt your data, the other one will be required on your server. First find out your key UID.

# gpg --list-key
/home/floreo/.gnupg/pubring.gpg
-------------------------------
pub   4096R/1A6F2256 2017-11-11
uid                  Floreo Backup (Floreo Backup) <xxx@floreo.info>
sub   4096R/874F94F5 2017-11-11
List your GnuPG keys

There the UID is 1A6F2256, you can export the keys.

# gpg --output backup_pub.gpg --armor --export 1A6F2256
# gpg --output backup.gpg --armor --export-secret-key 1A6F2256
Export both the pub and private keys

Import your public key

SSH to your server so you can import your key only, first upload the public key through scp for example.

# scp backup_pub.gpg xxx.xxx.xxx.xxx:/home/toto/.
SCP your public key to your server

Your public key being on your server you need to import it to gpg.

# gpg --import backup_pub.gpg
Import your public key.

You would think it’s over but you have to change the trust of the key, do the following command.

# gpg --edit 1A6F2256
Change the trust of your key

One you have the GNuPG prompt, type trust, select optimal, say yes and you’re done !

First server backup

Duplicity allows you to do full backups or incremental ones. Of course the first one is a full backup. One cool thing is that you don’t have to tell it explicitly to do an incremental one once the first one is made.

I suggest you use that very simple script to do your backup, you can edit it to your needs, mostly the exclude part. It backups fully on Monday, following days of the week are incremental. On Monday it also removes old backups, it’s done this dirty way since you cannot use duplicity’s cleanup function without the private key and the passphrase which I refuse to use online. It keeps two weeks of backup which is enough for me. You need to set an autofs mount to erase old backups since I didn’t script the FTP deletion yet.

Now run it, it may take a while so I recommend that you do that in a screen or tmux.

Rather than doing it manually, don’t forget to set a cron task to backup every night your data.

0 2 * * * root bash /root/scripts/backup.sh &>/dev/null
/etc/cron.d/backup

Restore your data

Obviously if you backup anything, you need to restore it some day soon. This time this operation requires the private key so you can decrypt the data ! Do what’s best for you, but it’s safer to keep your private key on your computer, you have to import your private key in gpg first.

# gpg --import backup.gpg 
gpg: key 1A6F2256: secret key imported
gpg: key 1A6F2256: public key "Floreo Backup (Floreo Backup) <xxx@floreo.info>" imported
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
gpg:       secret keys read: 1
gpg:   secret keys imported: 1
Import your private key to your local computer

Next step is really simple you have to revert the duplicity command to restore.

# export PASSPHRASE=<PASSPHRASE>
# export FTP_PASSWORD=<FTP PASSWORD>
# duplicity  ftp://<USER>@<HOST>/<REMOTE_DIRECTORY>/ <LOCAL_DIRECTORY>
# unset PASSPHRASE FTP_PASSWORD
Restore your encrypted data locally

Finally rsync your data to your server, I know it looks complicated but it makes sure that your private key is never on your server.

Do not forget to remove your private key from your computer, it’s safer too.

gpg --delete-secret-key 1A6F2256
Delete your imported private key

A word of advice if you have several backup chains, for example I backup fully on Monday and do incremental ones for other days and keep two weeks top, duplicity will show you only the last full backup even if you restore stuff before the last full backup. It’s weird, but your restoration would work, it would just display the wrong date. To be sure I check the last mail.log, you might do it as well.

Check that your backups are good quite often. For further details, you can find some more explanations following the Ubuntu documentation.

Secure and extend you Philips Hue bridge with a reverse proxy

Philips Hue bridge

Recently I bought a Hue bridge with two bulbs, it was a specific “cheap” pack around 50€, the bridge itself usually costs that price, so I was quite interested. My idea was just to play with those bulbs and do funny things such as blinking when I get new mail, etc … After messing with it for a while using the Philips HUE app on Android, I wanted to do more so I checked the API. It’s quite well made and allows you to do a lot on your own, though, I had in mind to hide my bridge in my own local network, for security purpose and also to add more functionalities to it, let’s see how to make a hue bridge reverse proxy !

Requirements

To do that, you need:

  • a router, your own home box is enough
  • a raspberry PI or any computer with Apache and PHP
  • (optional) a USB to ethernet adapter, I bought this cheap one
  • some time to configure it all !

Configure the bridge

Follow the official instructions to install your bridge, you have to connect it to your router, it needs an IP within your local network so we can reach it with an other computer.

Once it’s all set and that it got an IP, open up your web browser and go to the following URL: http://192.168.1.xxx/debug/clip.html, obviously set the IP address to the correct one.

Create a new user following the steps on the API documentation. Keep the generated hash around, it’s important to control your bridge.

Stay in your web browser in the debug and do a GET call to http://<ip-address.of.the.bridge>/api/<username>/config, it will look like that:

Get the bridge information

Get the bridge information

Copy the mac field and save it somewhere, it’s important.

Finally, we will configure the bridge to stop DHCP and also to take the IP we want it to get out of the local range.

Still in your browser, do a PUT request to http://<ip-address.of.the.bridge>/api/<username>/config with the following content:

{"ipaddress":"10.50.0.2", "dhcp":false, "netmask": "255.255.255.0", "gateway": "10.50.0.1" }
Do a PUT request to http://<ip-address.of.the.bridge>/api/<username>/config

Once you run it, you should lose the control to the bridge ! No worries, we’ll get it back.

Network adapter

If you bought the network adapter I suggested, it should look like that:

Network adapter in its blister

Network adapter in its blister

SSH to your raspberry pi, and check the network configuration:

 # ifconfig -a
 eth0      Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX
           inet adr:192.168.1.3  Bcast:192.168.1.255  Masque:255.255.255.0
           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
           RX packets:1575384 errors:0 dropped:62 overruns:0 frame:0
           TX packets:810579 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 lg file transmission:1000
           RX bytes:271762165 (259.1 MiB)  TX bytes:189260556 (180.4 MiB)
 
 lo        Link encap:Boucle locale
           inet adr:127.0.0.1  Masque:255.0.0.0
           UP LOOPBACK RUNNING  MTU:65536  Metric:1
           RX packets:4781492 errors:0 dropped:0 overruns:0 frame:0
           TX packets:4781492 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 lg file transmission:1
           RX bytes:402951806 (384.2 MiB)  TX bytes:402951806 (384.2 MiB)
ifconfig -a before plugging the adapter

Now plug the network adapter USB side to your PI, and connect the ethernet cable to the ethernet adapter.

Network adapter plugged

Network adapter plugged

We’ll check the adapter is working by doing the same command, but now we should see eth1 !

 # ifconfig -a
 eth0      Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX
           inet adr:192.168.1.3  Bcast:192.168.1.255  Masque:255.255.255.0
           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
           RX packets:1576244 errors:0 dropped:62 overruns:0 frame:0
           TX packets:811252 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 lg file transmission:1000
           RX bytes:271834756 (259.2 MiB)  TX bytes:189382050 (180.6 MiB)
 
 lo        Link encap:Boucle locale
           inet adr:127.0.0.1  Masque:255.0.0.0
           UP LOOPBACK RUNNING  MTU:65536  Metric:1
           RX packets:4781492 errors:0 dropped:0 overruns:0 frame:0
           TX packets:4781492 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 lg file transmission:1
           RX bytes:402951806 (384.2 MiB)  TX bytes:402951806 (384.2 MiB)

 eth1      Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX
           BROADCAST MULTICAST  MTU:1500  Metric:1
           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 lg file transmission:1000
           RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
ifconfig -a after plugging the adapter

Perfect, now let’s configure the network, edit the file /etc/network/interfaces by adding the following:

 auto eth1
 iface eth1 inet static
         address 10.50.0.1
         netmask 24
/etc/network/interfaces

Bring up eth1 end ping your bridge:

#  ifup eth1
 # ping 10.50.0.2
 PING 10.50.0.2 (10.50.0.2) 56(84) bytes of data.
 64 bytes from 10.50.0.2: icmp_seq=1 ttl=64 time=1.86 ms
 64 bytes from 10.50.0.2: icmp_seq=2 ttl=64 time=1.45 ms
 ^C
 --- 10.50.0.2 ping statistics ---
 2 packets transmitted, 2 received, 0% packet loss, time 1001ms
 rtt min/avg/max/mdev = 1.454/1.661/1.868/0.207 ms
Bring up eth1 and ping your bridge !

If it all works, you can move on to the HTTPS part, else, try using some networking tools such as tcpdump to determine what goes wrong.

HTTPS

New release of the Hue bridge uses HTTPS, of course it can’t rely on a real domain name since it’s connecting on the IP of the bridge and it can be different, after doing some reverse engineering it I found out how it works. Actually every bridge as an ID. Now that the link between your PI and the bridge is UP you can get your ID easily and prepare to create your own HTTPS certificate.

# openssl s_client -showcerts -connect 10.50.0.2:443 </dev/null
...
---
Server certificate
subject=/C=NL/O=Philips Hue/CN=00xxxxxxxx
issuer=/C=NL/O=Philips Hue/CN=00xxxxxxxx
---
...
Check what's the CN of your bridge

So there you go you have your CN which is actually what’s necessary to create your own HTTPS certificate. If you want to change your ID, you can, you’ll have to change it also in the PHP below.

First create a directory to store your key, certificate.

# mkdir -p /etc/ssl/hue
Create the /etc/ssl/hue directory

Now the key and the certificate

# openssl req -newkey rsa:4096 -nodes -keyout key_hue.pem -x509 -days 3650 -out certificate_hue.pem
Create your self signed certificate

The only parameter that matters here is the CN, put a correct bridge ID, in my case I just changed a few values.

Finally just concat both files to create a pem.

# cat certificate_hue.pem key_hue.pem > pem_hue.pem
Create the full certificate

A word of advice, as of now (version 1806051111 of the bridge), the hue app will use HTTPS to connect to the bridge, the first time you validate the connection it will stick the certificate. If you ever change the certificate, you’ll have to remove the credentials in your Android/iOS (i.e clear all data of the app) and press on the button again.

Second word of advice, if you test a lot, be careful to keep clean your whitelist user, it gets messy very fast ! You can delete some doing a DELETE request on /api/userYouControl/config/whitelist/userYouWishTodelete

Reverse proxy

Do you remember the MAC address of your bridge ? If, as I previously said you did, then we will use it pretty soon.

Stay on your PI and open up again /etc/network/interfaces, we will change the mac address of eth0 so if it will be seen as a HUE bridge for the mobile apps. You can use the mac address of the real bridge and alter it so it’s different, I suggest you use this website to make it sure it’s still seen as “Philips Lighting BV“.

auto eth0
iface eth0 inet static
        address 192.168.1.2
        netmask 24
        gateway 192.168.1.254
        dns-nameservers 127.0.0.1
        # faking MAC address to Philips HUE style
        hwaddress ether 00:17:88:78:45:12
Change the mac address

Now on your home box, set the IP of your PI as a static one for this tutorial it will be 192.168.1.3.

It’s time to install haproxy, apache and php, I won’t describe this here, do as you wish, we’ll just go through what’s really important.

There goes a valid haproxy configuration:

# Faking Hue Bridge requires HTTPS now

frontend f_http_hue
        mode http
        bind 192.168.1.3:80
        use_backend b_http_hue

frontend f_https_hue
        mode http
        bind 192.168.1.3:443 ssl crt /etc/ssl/hue/pem_hue.pem
        use_backend b_http_hue

backend b_http_hue
        mode http
        server bridge 127.0.0.1:8080
/etc/haproxy/haproxy.cfg

Install mod_proxy and mod_http_proxy, create a new virtualhost /etc/apache2/sites-available/hue.conf this way:

<VirtualHost 127.0.0.1:8080>
    DocumentRoot /var/www
    ServerName xxxxxxx
    CustomLog /var/log/apache2/hue_access.log combined env=!forwarded
    CustomLog /var/log/apache2/hue_access.log proxy env=forwarded
    ErrorLog /var/log/apache2/hue_error.log

    RewriteEngine On
    RewriteCond %{REQUEST_URI}  ^$ [OR]
    RewriteCond %{REQUEST_URI}  ^/$ [OR]
    RewriteCond %{REQUEST_URI}  \.png$ [OR]
    RewriteCond %{REQUEST_URI}  \.xml$ [OR]
    RewriteCond %{REQUEST_URI}  ^/debug/clip.html
    RewriteRule (.*)              http://10.50.0.2$1    [P,L]

    RewriteRule ^(/api.*)$ /index.php?q=$1 [L,QSA]
</VirtualHost>
/etc/apache2/sites-available/hue.conf

Activate it and edit /var/www/index.php:

<?php
/*
* Activate proxy_module and proxy_http_module
*/

ignore_user_abort(true);

$mac_address = [ '<mac address of the real bridge>',  '<your fake Philips HUE mac address>' ];
$ip_hue = [ '<ip of the real bridge>', '<ip of your PI>' ];
$bridge_id = [ '<the real bridge id>', '<faked id bridge>' ];
$gateway_hue = [ '<ip of your PI>', '<gateway of your local network>' ];
$url = 'http://10.50.0.2'.$_SERVER['REQUEST_URI'];
$useDB = false;

$options =[ 
    'http' => [
        'header'  => "Accept-Encoding: gzip, deflate\r\nAccept-language: en-US,en;q=0.8\r\nUser-Agent: ".$_SERVER["HTTP_USER_AGENT"]."\r\n",
        'method'  => $_SERVER["REQUEST_METHOD"],
    ]
];

if($_SERVER["REQUEST_METHOD"] !== 'GET' ){
    $options['http']['header'] .= "Content-type: application/x-www-form-urlencoded\r\n";
    $options['http']['content'] = file_get_contents("php://input");
}

$context  = stream_context_create($options);
$result = file_get_contents($url, false, $context);
if ($result === FALSE) {  }

// faking HUE bridge EDIT: 13/08, it needs to be faked all the time now
$result = str_replace($mac_address[0], $mac_address[1], $result);
$result = str_replace($ip_hue[0], $ip_hue[1], $result);
$result = str_replace($gateway_hue[0], $gateway_hue[1], $result);
$result = str_replace($bridge_id[0], $bridge_id[1], $result);

ob_start();
echo $result;
$size = ob_get_length();
header("Content-Length: {$size}");
header("Connection: close");
ob_end_flush();
ob_flush();
flush();

/** DB part **/
if($useDB){

    $_user = '';
    $_password = '';
    $_database = '';
    $_host = '';

    try {
	$_db_link = new PDO('mysql:host='.$_host.';dbname='.$_database.';charset=utf8', $_user, $_password);
    } catch (Exception $e) {
        die('Erreur : ' . $e->getMessage());
    }

    $stmt = $_db_link->prepare("INSERT INTO hue_log (ip, method, url, content) VALUES (:ip, :method, :url, :content)");
    $stmt->bindParam(':ip', hash('sha256', $_SERVER['REMOTE_ADDR']));
    $stmt->bindParam(':method', $_SERVER['REQUEST_METHOD']);
    $stmt->bindParam(':url', $_SERVER['REQUEST_URI']);
    $stmt->bindParam(':content', $result);
    $stmt->execute();
}

Now restart Apache and open your browser on http://192.168.1.3, it should load ! Check the logs of Apache, you should also see some requests.

Philips’ upgrades

I didn’t mention it, because I hadn’t figure it yet, but all the Philips’ Upgrades won’t be done anymore since the bridge has no internet access. I found out one way to do it, it’s tricky but anyone can do it.

I use the Hue App on my mobile to control lights, it tells you when some upgrades are required, it’s how I know I should run them. When it happens, I simply forward packets from my bridge to my PI and force the update thought the API, let’s do it.

Allow packet forwarding and forward the bridge to the PI:

 echo 1 > /proc/sys/net/ipv4/ip_forward
 iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
 iptables -A FORWARD -i eth0 -o eth1 -m state --state RELATED,ESTABLISHED -j ACCEPT
 iptables -A FORWARD -i eth1 -o eth0 -j ACCEPT
Allow kernel forwarding and forward bridge to the PI

You should notice that the third light is now lit, it reaches internet, no worries we open it up only temporarily.

Connect to the API and run the following commands:

 {
         "portalservices": true
 }
Do a PUT request to http://<ip-address.of.the.bridge>/api/<username>/config
{"swupdate": {"checkforupdate":true}}
Do a PUT request to http://<ip-address.of.the.bridge>/api/<username>/config
 {
         "swupdate": {
                     "updatestate": 3
                         }
 }
Do a PUT request to http://<ip-address.of.the.bridge>/api/<username>/config

It should download the update, restart your bridge, launch the update from your mobile app, sometimes it’s quite long ! To update three bulbs it took me around 1 hour, it depends on the update.

Once everything is done, cut the bridge from the internet:

 iptables -F nat
 iptables -F FORWARD
 echo 0 > /proc/sys/net/ipv4/ip_forward
Clean up the firewall and shut down forwarding

Reboot it once again so remaining connections will be stopped. Only two lights should remain.

You might check that your bridge is really off the internet by doing a GET request to http://<ip-address.of.the.bridge>/api/<username>/config, you should have that:

     "portalstate": {
         "signedon": false,
         "incoming": false,
         "outgoing": false,
         "communication": "disconnected"
     },
     "internetservices": {
         "internet": "disconnected",
         "remoteaccess": "disconnected",
         "time": "disconnected",
         "swupdate": "disconnected"
     },
Content of the GET to http://<ip-address.of.the.bridge>/api/<username>/config

Also, it’s possible you do a tcpdump to check to what your bridge tries to contact, it might amuse you.

Sources for the upgrades:

Epilogue

Your HUE bridge is hidden behind your raspberry PI, it’s secure moreover you can also edit the PHP to add new functionality !

Convert a physical server to a virtual one

Introduction

I needed to “convert” a physical server to a virtual one, in this case I couldn’t and didn’t want to make the same disk partitioning size, but if that’s your case  you can still read. To be more specific, by convert I mean, not to reinstall every services on a brand new virtual machine but simply run what’s on the physical machine. Two reasons, my laziness and most importantly the fact that I’m not sure what was running on. Here goes one solution to do it, we’ll follow these steps:

  • full backup of the physical server
  • prepare the new virtual server on VirtualBox or what you prefer (KVM, etc …)
  • import the backup inside our virtual server’s drive
  • chroot using sytemrescue to update the MBR
  • boot our virtual server
  • Adapt some configuration

Backup !

First things first, do a full backup of your physical server, you can do it that way (adapt it to your use case):

tar -zcvpf mybackup.tar.gz --exclude=/archive --exclude=/mnt --exclude=/proc --exclude=/lost+found --exclude=/dev --exclude=/sys --exclude=/tmp /
Full backup of your server

Be careful with the owners and rights of your files !

Keep that backup somewhere close, we’ll reimport it later.

Virtual Server’s configuration

I’ll only explain how to do it on VirtualBox, if you don’t have it running yet, install it and start it.

Create your new virtual server by clicking on “New”, set your name, your OS type and the version. Just set the parameters as you wish, it depends on your physical server on what you want. Though, once you reach the configuration for the disk, choose vdi and make it a fixed size, it’s quite important for later.

Now your virtual server’s “hardware” configuration is almost done, just set some other settings to your convenience such as the network, boot order (for our test it’s best to select CD first) etc …

We’ll need systemrescue, so download it. Once you have the iso, select it in VirtualBox for your virtual server to boot on. Start it !

This step is about partitioning, so be sure of what you want and what you do. You can simply recreate the same partitions you have on your physical server or just set new ones, just be sure to put enough space for your data to fit in.

qemu-utils and our data

To reimport our data inside the vdi disk we have in VirtualBox we’ll use a cool tool inside qemu-utils. Poweroff your virtual server, it’s very important to not ruin your vdi. Let’s install it and see what we can do with it:

aptitude install qemu-utils
modprod nbd
Install qemu-utils

We need to activate the kernel module nbd too.

Now we’ll link a device /dev/nbd0 to our vdi disk:

qemu-nbd -c /dev/nbd0 <path to your vdi disk>.vdi
Link vdi disk to /dev/nbd0

Create mountpoint directories and mount your partitions:

mount /dev/nbd0p1 /mnt/vs1/boot/
mount /dev/nbd0p3 /mnt/vs1/root/
Mount your partitions

You can now rsync your backup data inside your partitions !

Once your done let’s clean up:

umount /mnt/vs1/root
umount /mnt/vs1/boot
qemu-nbd -d /dev/nbd0
Clean up

Chroot time

Our data is now inside our vdi disk, great, but we can’t boot directly because our MBR doesn’t exist. We need to fix that. Reboot your virtual server on systemrescue. Once you have the prompt you’ll chroot:

mkdir -p /mnt/root/boot
mount /dev/sda3 /mnt/root
mount /dev/sda1 /mnt/root/boot
mkdir /mnt/root/{sys,proc,dev,run,tmp}
mount --bind /proc /mnt/root/proc
mount --bind /sys /mnt/root/sys
mount --bind /dev /mnt/root/dev
mount --bind /run /mnt/root/run
mount --bind /tmp /mnt/root/tmp
chroot /mnt/root /bin/bash
Chroot

If everything went well, you should be “inside” your physical server (as if), check a few files you know to be sure it’s well chrooted (/etc/hosts, content of /home, etc ..) if it’s alright, we can now update the MBR:

update-grub
grub-install /dev/sda
update the MBR

If the commands didn’t yell at you, it’s looking pretty good, you can now poweroff your virtual server. Remove the systemrescue iso and boot your virtual server on its vdi disk, it should work 🙂

Adapt your configurations

A few examples about problems I ran into:

  • careful with your /etc/fstab if you used UUID, you’ll have to change your fstab with a chroot
  • if you didn’t keep the correct owners and rights of your data, it’s possible the virtual server will boot and couldn’t access the data, it will probably try to use a wrong user because of the suid
  • probably a part of your network configuration won’t work, or worse your access to the virtual server, you can clean your firewall with a chroot and then set a NAT rule in VirtualBox to access the machine. In my case, since I had only SSH to my physical server, the keyboard layout was US, and since I have an azerty keyboard it was a pain in the ass. I couldn’t edit easily any file. I decided to SSH on the virtual machine using a NAT rule and to install later the correct layout.

Midi sound with Wine/PlayOnLinux

Introduction

I’ve always loved Guitar Pro 5 as a quite good tool to learn and practice tabs, there are new versions, but I stick to that one. Sadly it only runs on Windows and I don’t have one anymore therefore I decided to run it using PlayOnLinux. After installing Guitar Pro 5 quite easily, I came across one main problem, I had no midi sound. The problem is not only related to Guitar pro, but is related to the need of midi with PlayOnLinux or Wine.

Timidity

As the man says, timidity is a “MIDI-to-WAVE converter and player”,  it simply means for us that it will do the trick between our OS and the software inside PlayOnLinux. Up in !

Let’s install timidity and freepats:

# aptitude install timidity freepats
Install timidity and freepats

Now that we have timidity we just need to make a wrapper to start Guitar Pro 5, or any other software. You can use this script and adapt it to your needs:

#!/usr/bin/env bash

# starting timdity
timidity -iA -B2,8 -Os -EFreverb=0 &

# get timidity's PID
_PID="$!"

# start GP5
/usr/share/playonlinux/playonlinux --run "GP5"

# clean up
kill -9 ${_PID}

Quite simple, we just start timidity then our software, here GP5 is the name of my virtual drive in PlayOnLinux, and we kill timidity. Yeah the kill is bad but SIGQUIT wouldn’t work, I got tired.

Don’t forget to chmod it to be executable.

Finally we can make a shortcut on our desktop (~/GP5.desktop):

[Desktop Entry]
Encoding=UTF-8
Name=GP5
Comment=PlayOnLinux
Type=Application
Exec=/home/floreo/Workspace/scripts/GP5.sh
Icon=/home/floreo/.PlayOnLinux//icones/full_size/GP5
Name[fr_FR]=GP5
StartupWMClass=GP5.exe
Categories=
Path=
Terminal=false
StartupNotify=false
GP5.desktop

As you may notice, line 6 is the call to our wrapper.

Configure MIDI output in Guitar Pro 5

For those who don’t know and are interested about Guitar Pro 5’s audio configuration, once you are done with the setup I’ve shown, you still need to configure the correct MIDI output. In Guitar Pro 5, go to Options > Audio Settings (MIDI/RSE). Select TiMidity port 0 as the first port output device.

GP5 audio settings MIDI

Select TiMidity port 0 as first device MIDI output

Troubleshooting

I didn’t use it enough yet, but I got some cracking sound sometimes, for now I save what i’m doing in Guitar Pro and restart it. I guess the problem could be solved by giving extra parameters to timidity. If I find anything I’ll let you know.