Wednesday, 24 May 2017

Raspberry Pi - WiFi not working

I've recently had to investigate why the onboard WiFi connection on one of my Raspberry Pi V3 models wasn't working. I'm sure that this stopped working after an update but I cannot be certain. The following information only applies to the onboard WiFi on a Pi V3 - I don't need or require a separate USB WiFi dongle.

Troubleshooting turned out to be quite involved. I had tried to perform the usual commands of disabling and then re-enabling the WiFi interface (sudo ifdown wlan0 && sudo ifup wlan0) to no avail.

Reinstalled wpasupplicant package - still nothing. This action blatted my /etc/wpa_supplicant/wpa_supplicant.conf file so I recreated that from a working Raspberry Pi:

C3PI6:/run $ sudo cat /etc/wpa_supplicant/wpa_supplicant.conf
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=GB

network={
        ssid="Insert_your_WIFI_network_name_here"
        psk="Insert_your_WIFI_password_here"
        key_mgmt=WPA-PSK
}


My system tray icon resolutely refused to play ball and was showing the dreaded 'No wireless interfaces found'. Working from a Korn shell, I went back to basics and monitored the syslog output to see if I could work out where it was going wrong. After issuing the interface down command (sudo ifdown wlan0) I could see that I was getting an error about the lockfile state, or rather the lack of one. I saw that the directory of /run/network wasn't present so I created that. I created the lockfile by using the 'touch' command to simply touch the file and therefore create it:

C3PI6:/home/pi $ sudo ifdown wlan0
ifdown: failed to open lockfile /run/network/.ifstate.lock: No such file or directory
C3PI6:/home/pi $ sudo touch /run/network/.ifstate.lock
touch: cannot touch ‘/run/network/.ifstate.lock’: No such file or directory
C3PI6:/home/pi $ cd /run
C3PI6:/run $ cd network
-ksh93: cd: network: [No such file or directory]
C3PI6:/run $ sudo mkdir network
C3PI6:/run $ sudo touch /run/network/.ifstate.lock

C3PI6:/run $ sudo ifdown wlan0
ifdown: interface wlan0 not configured

C3PI6:/run $ sudo ifup wlan0
May 24 11:48:43 C3PI6 kernel: [  364.071977] brcmfmac: power management disabled
May 24 11:48:43 C3PI6 wpa_supplicant[2015]: Successfully initialized wpa_supplicant
May 24 11:48:44 C3PI6 wpa_supplicant[2018]: wlan0: CTRL-EVENT-REGDOM-CHANGE init=USER type=COUNTRY alpha2=GB
May 24 11:48:44 C3PI6 systemd[1]: Reloading OpenBSD Secure Shell server.
May 24 11:48:44 C3PI6 systemd[1]: Reloaded OpenBSD Secure Shell server.
May 24 11:48:44 C3PI6 wpa_supplicant[2018]: wlan0: Trying to associate with 00:24:a5:bc:2f:e5 (SSID='Johnnys_WIFI_working' freq=2447 MHz)
May 24 11:48:44 C3PI6 wpa_supplicant[2018]: wlan0: Associated with 00:24:a5:bc:2f:e5
May 24 11:48:44 C3PI6 wpa_supplicant[2018]: wlan0: WPA: Key negotiation completed with 00:24:a5:bc:2f:e5 [PTK=CCMP GTK=TKIP]
May 24 11:48:44 C3PI6 wpa_supplicant[2018]: wlan0: CTRL-EVENT-CONNECTED - Connection to 00:24:a5:bc:2f:e5 completed [id=0 id_str=]
May 24 11:48:44 C3PI6 dhcpcd[384]: wlan0: carrier acquired
May 24 11:48:44 C3PI6 dhcpcd[384]: wlan0: IAID eb:9b:ad:32
May 24 11:48:45 C3PI6 dhcpcd[384]: wlan0: soliciting a DHCP lease
May 24 11:48:45 C3PI6 dhcpcd[384]: wlan0: offered 192.168.1.106 from 192.168.1.1
May 24 11:48:45 C3PI6 dhcpcd[384]: wlan0: soliciting an IPv6 router
May 24 11:48:50 C3PI6 dhcpcd[384]: wlan0: leased 192.168.1.106 for 86400 seconds
May 24 11:48:50 C3PI6 avahi-daemon[379]: Joining mDNS multicast group on interface wlan0.IPv4 with address 192.168.1.106.
May 24 11:48:50 C3PI6 avahi-daemon[379]: New relevant interface wlan0.IPv4 for mDNS.
May 24 11:48:50 C3PI6 dhcpcd[384]: wlan0: adding route to 192.168.1.0/24
May 24 11:48:50 C3PI6 avahi-daemon[379]: Registering new address record for 192.168.1.106 on wlan0.IPv4.
May 24 11:48:50 C3PI6 dhcpcd[384]: wlan0: adding default route via 192.168.1.1
May 24 11:48:52 C3PI6 ntpd[611]: Listen normally on 4 wlan0 192.168.1.106 UDP 123
May 24 11:48:52 C3PI6 ntpd[611]: peers refreshed

As you can see from the above, my WiFi is now working on IP 192.168.1.106 and I can therefore disconnect the Ethernet cable as this Pi runs headless and wireless.

Please note - check that you have the following packages installed, and if not, install them: wireless-regdb, crda, iw

The eagle-eyed amongst you will have noted that I have turned off power-management of the WiFi interface as this can cause problems/instability. I have included a copy of the file that is located at /etc/network/interfaces:

C3PI6:/var/log/apt $ cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)

# Please note that this file is written to be used with dhcpcd
# For static IP, consult /etc/dhcpcd.conf and 'man dhcpcd.conf'

# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d

auto lo
iface lo inet loopback

iface eth0 inet manual

allow-hotplug wlan0
iface wlan0 inet manual
    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
wireless-power off

Note - the last line/entry shows the power management switched off.

Tuesday, 7 February 2017

Raspberry Pi V1 - Wheezy vs Jessie

I've had many Raspberry Pi computers, with most of them being either V2 or V3 but I do have one of the original version 1 Pi computers - this one has only 512MB of RAM and a single core/processor. Whilst in the process of reallocation of duties, I decided to set this one up in 'Kiosk mode' so that I can display the webcam output from one of my more powerful Pi3 computers.

I hit loads of problems with trying to get motion working as it all seems to be geared towards the Jessie release, and my Pi1 was running Wheezy. I thought that it would be good to go back to square one and start afresh. I went to search on the internet to find a download site for the Wheezy image of Raspbian and hit a problem as the Raspberry Pi website only lists current releases i.e. Jessie and that won't work with mine as it's armhf as opposed to armv6l

Anyways, long story short and all that. After much searching, I came across this URL after trwaling through the forums:

Raspberry Pi V1 Wheezy image
.
https://downloads.raspberrypi.org/raspbian/images/raspbian-2015-05-07/

Hope this helps.

Friday, 8 July 2016

Flashing taskbar on Raspberry Pi?

Recently I encountered an issue with the Raspberry Pi where the taskbar kept flashing on and off, perhaps once every second or so.

After much digging around on 'tinterweb', I found that the solution was to remove the following entry for alsa in the following file:

~/.config/lxpanel/LXDE-pi/panels/panel

Removed the entry:

Plugin {
type=volumealsa
Config {
}
}

Saved the file, rebooted the Pi (I don't think the reboot is essential though) and all now works perfectly! Hope this helps you.

Tuesday, 5 July 2016

Raspberry Pi - Wheezy image - no systemd

I just hate systemd and will not have it on any of my Linux systems. Raspbian, the OS installed on my Raspberry Pi systems, is now set to default and install systemd on the Jessie version so my preference is for Wheezy which uses init instead, innit?

Locating the image file is getting harder as time goes by, so I've stuck a copy of the image file on my web server. You can download the zipped up image file from here: WHEEZY

Bye bye systemd.

Sunday, 1 May 2016

Lync client for Linux, called Wync

I have to use the Microsoft Lync client at work on a work-supplied laptop, but when I'm working from home I tend to use my own Linux server to connect up and of course, that excludes me from using Lync.

I did some fishing around on the internet and was delighted to discover that there was a Linux client available to download from http://fisil.com/ - this link still works but there is no trace of the Wync client. Recently, I've had the need to use Wync under Linux but it didn't seem to be available anywhere. I tried general Google searches and also searched with the aptitude tool from the shell i.e. sudo aptitude search wync and came up with nothing.

I then hit on the idea of using the Wayback Machine (Internet Archive) and to my delight, I was able to download the 64-bit .deb file - this is now hosted on my server and you can download it from the following link:

Wync - Lync for Linux (64-bit deb file)

Tuesday, 19 April 2016

KODI on OpenElec / Raspberry Pi - unable to view TV shows via sftp

I encountered an issue recently where my main server that is the repository of all my TV recordings had been rebuilt. It was only after a bit of standard troubleshooting that I managed to figure out that the reason for being unable to connect was because the SSH key had changed.

When connecting from the Pi to the main server, I was hit with this error:

OpenELEC:~ # ssh -oPort=44 -l john 192.168.1.44
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the ED25519 key sent by the remote host is
SHA256:long_spangly_key
Please contact your system administrator.
Add correct host key in /storage/.ssh/known_hosts to get rid of this message.
Offending ED25519 key in /storage/.ssh/known_hosts:1
ED25519 host key for [192.168.1.44]:44 has changed and you have requested strict checking.
Host key verification failed.


I edited the requisite file in /storage/.ssh/known_hosts and removed the offending key on line 1, using my trusty vi editor.

I attempted to connect again:


OpenELEC:~ # ssh -oPort=44 -l john 192.168.1.44
The authenticity of host '[192.168.1.44]:44 ([192.168.1.44]:44)' can't be established.
ECDSA key fingerprint is SHA256:long_spangly_key
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '[192.168.1.44]:44' (ECDSA) to the list of known hosts.
john@192.168.1.44's password:
Welcome to Linux Mint 17.1 Rebecca (GNU/Linux 3.13.0-37-generic x86_64)

Welcome to Linux Mint
 * Documentation:  http://www.linuxmint.com
No mail.
Last login: Sat Apr 16 20:26:46 2016 from ch1-fw1-dip.uk.clara.net
$


Success!

I am now able to successfully browse all of my TV programs using ssh/sftp.

(NOTE -  key value in the above example has been obfuscated - long_spangly_key)

Thursday, 14 April 2016

Webmin - themes

Webmin now has a new theme called 'Authentic'. It looks really good, is pleasant on the eye so what is there not to like about this?

SLOW

In a word, slow.

it's slower than a pig in treacle. I really like the look of this theme but the response times from my server when trying to perform simple actions via Webmin are simply too slow to be acceptable.

I've switched now to one of my 'old' favourites which was designed by Swell Technologies. You should be able to find it on the tinterweb as a .wbt file but if you have any trouble, I've uploaded it to my server - it's around 3Mb in size.


Tuesday, 9 February 2016

Autologin function on Linux Mint

I was recently unable to get to my desktop remotely after a reboot of Linux Mint.
If you have remote access via ssh (Secure Shell) on PuTTy or KiTTy, then you can edit a file, make the necessary changes listed below and then go for the reboot option:

File that needs to be changed is etc/mdm/mdm.conf

Check the contents of the file first:

less /etc/mdm/mdm.conf | grep -v \# | grep .
[daemon]
AutomaticLoginEnable=false
AutomaticLogin=
[security]
[xdmcp]
[gui]
[greeter]
[chooser]
[debug]
[servers]


Change the file using the 'vi' editor preferably.

vi /etc/mdm/mdm.conf and change the lines marked for AutomaticLoginEnable as true, and AutomaticLogin to the user that you want to set as auto-login. I've set mine to user-id John because that's me.

less /etc/mdm/mdm.conf | grep -v \# | grep .
[daemon]
AutomaticLoginEnable=true
AutomaticLogin=john
[security]
[xdmcp]
[gui]
[greeter]
[chooser]
[debug]
[servers]


Save the file and reboot. You should now have access to the GUI.

Sunday, 12 July 2015

Freecom firmware - USB TV dongle/stick

I was trying recently to get one of my old Freecom USB TV sticks working, and was unable to load the missing firmware file. I performed a search on Google and came across not only my missing firmware file named dvb-usb-wt220u-02.fw but 3 others so I've taken the chance to upload these on hosted web space and they are listed below for reference/download.

dvb-usb-wt220u-01.fw

dvb-usb-wt220u-02.fw

dvb-usb-wt220u-fc03.fw

dvb-usb-wt220u-zl0353-01.fw

Respect to Chandler's Zen.

Wednesday, 10 June 2015

Lightscribe on Linux Mint

I was somewhat disappointed to find out that the old Lightscribe website doesn't work any more so I had a dig around on my system archives and found a couple of .deb packages which, after installation, seem to work perfectly.

You can download them from here:

Lightscribe
Lightscribe_Application

The utility gets installed to the following location on my Linux Mint 17 install:

/opt/lightscribeApplications/SimpleLabeler/SimpleLabeler

When used with the K3b application to burn the DVD/CD, it all works perfectly.

Monday, 13 April 2015

Harty Church, Isle of Sheppey

I took my goddaughter Hannah with me on the 25th June 2013 to commemorate my brother Mark, who sadly passed away in 1999. We travelled down to the island and spent a wonderful day together, for which I am forever grateful.

The sun was shining and the weather was beautiful. Whilst touring around the Isle of Sheppey, we decided to visit the church in Harty, close to where the old Harty Ferry used to run from. The Church of Saint Thomas the Apostle at Harty was built around 1089 AD.


As you can no doubt see from the photograph, the church makes for a lovely picture.

[Taken on a Panasonic Lumix DMC LZ20 bridge camera, date 25.06.2013 at 15:11]

Monday, 16 March 2015

Stop systemd spamming the syslog with entries from ftp

Not content with systemd clambering all over my Ubuntu box, I went on a rather lengthy voyage of discovery trying to find out why each and every single ftp transaction was cluttering up my syslog, despite having the usual two logs in my /var/log/proftpd path.

Every time my webcam uploaded a single JPEG photo/snapshot, systemd made entries in my syslog, a minimum of 3 lines at a time. If you know me at all, there's nothing I hate more than 'not being able to see the wood for the trees'. All these entries made looking through my syslog a real chore. systemd is the biggest piece of crap. I'm going to be looking at Devuan in the very near future. Anyway, rant over. Here's how to disable the barking-mad systemd entries for ftp transactions in the syslog:

R2D2:/ $ sudo /usr/bin/systemd-analyze set-log-level notice

You will need to add this line to the file /etc/rc.local so that it runs on boot.

Wednesday, 22 October 2014

Change screenlock timeout from script - Ubuntu 14.04

My screen is set to blank/timeout after 3 minutes but I find it a real pain to have to go to the menus and then select the 'Brightness & Lock' applet in order to just change the timeout.

Since I love using the shell so much, I thought that I'd investigate seeing if I could achieve the same result via scripting. After a bit of confusion as to which command I should be using (gconf/dconf/gsettings), I discovered the correct way of poking the new values is by using dconf:

dconf write /org/gnome/desktop/session/idle-delay 'uint32 180'
Sets the delay for 3 minutes.

dconf write /org/gnome/desktop/session/idle-delay 'uint32 600'
Sets the delay for 10 minutes.

dconf write /org/gnome/desktop/session/idle-delay 'uint32 3600'
Sets the delay for 1 hour.

Note - you don't need to sudo these commands.

Respect to Jani for pointing me in the right direction.

Friday, 29 August 2014

Black box in notification area on Ubuntu 14.04

I've had this annoying problem for a while now, where a black rectangular box appears on my Ubuntu desktop, running Cairo Dock. Most of the links I found on Google didn't pinpoint anything useful so I sat down one day and killed off processes manually, one by one, in an effort to locate the source of my problem.

It would appear that the culprit is update-manager. The process was listed as running with an option/switch of --no-focus-on-map. The full process is shown below:

john     14771     1  0 Aug04 ?        00:00:11 /usr/bin/python3 /usr/bin/update-manager --no-update --no-focus-on-map

lsof -p 14771 shows that /usr/bin/python3.4 is involved, but not sure if that information is of any use.


You can't move the box or do anything with it. The most annoying thing is that it is 'Always on top' so you cannot see anything behind it.

Simply issue the following command at the shell:

killall update-manager


Tuesday, 29 October 2013

Slowdown on Ubuntu 13.10, CPU for accounts-daemon

My HP Microserver recently started to run like Herbert's dog on Family Guy, for no apparent reason. It seemed to slow things down when logging in to the desktop GUI. Boot was fine, as I run via an 80Gb SSD but logging in was soooo slow.

Whilst the GUI was taking about 1 minute or so, I switched to a console session (Ctrl-Alt-F1) and saw that there seemed to be 2 processes caning the CPU. The first culprit seemed to be /usr/lib/accountsservice/accounts-daemon whilst the second process was gnome-settings-daemon.

My first kludge was to simply write a script to kill the processes after logging in but that was only a temporary solution. I was still faced with the delay attempting to log in.

Further digging around on the internet showed that it was more than likely due to updates installed recently with regard to the following 3 bits of software:

glib-networking
glib-networking-common
glib-networking-services


Some posters on the thread at http://ubuntuforums.org/showthread.php?t=1970326&page=4 suggested that it only affected 64 bit versions of Ubuntu and that you were able to install an older package version.


I elected to follow the advice given by poster adamiak where he suggested using the following command:


sudo apt-get build-dep accountsservice

(I performed this because I'd previously experienced dependency problems when trying to build the alternative accountsservice listed below - I was missing libpolkit-gobject-1)

I then followed the advice offered by a previous poster ambrosa about building/compiling a version of accountsservice from scratch:

download http://www.freedesktop.org/software/...-0.6.20.tar.xz and extract with
tar xvf accountsservice-0.6.20.tar.xz
cd accountsservice-0.6.20
./configure
make


Replaced the original daemon with newly compiled version (making a backup first)
sudo cp -a /usr/lib/accountsservice/accounts-daemon /usr/lib/accountsservice/accounts-daemon.bak
sudo killall accounts-daemon
sudo cp src/accounts-daemon /usr/lib/accountsservice/accounts-daemon

 

This solved the problem after a reboot and all is now working perfectly. It took me a while to figure out what was going on so I'm sharing my experience as it may help others :-) 

N.B. You will probably have noticed a whole heap of new users listed on the login screen - I am now going to search to find out how to remove those errant users I have no need for.

Cheers. 

Tuesday, 3 September 2013

Uruguayan architect Rafael Viñoly making a name for himself

Uruguayan architect Rafael Viñoly

He appears to be making a name for himself recently in London. There's a new building, affectionately dubbed the 'walkie-talkie' which has made the news recently. Sunlight appears to be reflected from the building at 20 Fenchurch Street directly into one of the local roads. So intense is the effect that a car has 'melted', a doormat has caught fire and the saddle of a parked bicycle started smoking...

It looks like he's got previous on this - look at the Vdara Hotel in Las Vegas. Designed by the same architect, this one exhibits a similar problem which has been described as the 'Vdara death ray'.

My advice - don't look up to admire the building, which surely negates the desired effect of having designed an attractive building in the first place?

Thursday, 13 December 2012

New toy for the car, full HD camera and GPS system

BlackVue 16GB DR400G HD II
Full HD video 1920 x 1080 @30fps
GPS Version


I've just purchased this item and installed it in my vehicle. I recently suffered some vandal damage (3 tyres were punctured) and I wanted to catch the cretins in action.

I've already witnessed some poor lost soul navigating a roundabout the WRONG way and also seen a mugging. It's come in very useful so far and a friend who saw the video quality bought one immediately - he was that impressed.

Have a nose at my YouTube channel - search for montevideobadboy

Evolution 2.32.2 email client - exporting to new PC

For those of you that have been reading my blog, you'll know that I recently acquired an HP Microserver N40L. It now has two extra HDDs added, in the shape of a couple of 1.5Tb units from Western Digital.

Now that I have the extra capacity, I set about the onerous task of copying the data across from my main PC's Evolution (version 2.32.2) email data store and onwards to its new destination on the HP micro-server.

I used the 'File | Backup Evolution settings' option on the source client's Evolution app to make a tar.gz backup of all the necessary files - or so I thought.

The import on the new system took ages (4.5GB of data) but eventually completed, almost. It finished but then started off again with the same prompt i.e. Import data etc. At this point, I shut Evolution down on the new server and went back to my old PC.

Having done most of the grunt work, you will still need to export some other data via the gconftool-2 utility:


gconftool-2 --dump /apps/evolution > pc_evolution_data.xml

On new PC, do the following:

gconftool-2 --load pc_evolution_data.xml

I fired up Evolution on the new PC/micro-server and it all worked fine. All I then had to do was enter the passwords for my email accounts.