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by DougieLawson
Tue Jul 09, 2019 11:28 am
Forum: Troubleshooting
Topic: Network fails after rebooting but fine after shutting down
Replies: 66
Views: 1507

Re: Network fails after rebooting but fine after shutting down

epoch1970 wrote:
Tue Jul 09, 2019 11:26 am
yanewby wrote:
Tue Jul 09, 2019 11:24 am
I have no lines containing "ip=" in /boot/config.txt. Should there be one?
No. Only for network/NFS booting.
There was a habit of folks using that to get a fixed IP address. Not just for NFS.
by DougieLawson
Tue Jul 09, 2019 11:24 am
Forum: Troubleshooting
Topic: RPi 4 cannot connect to WiFi
Replies: 11
Views: 286

Re: RPi 4 cannot connect to WiFi

What happens if you sit with your RPi4 in the same room less than 10 meters from your access point?

Also wire it to your router for ten minutes and run the following

sudo apt update
sudo apt dist-upgrade -y
sudo apt install rpi-update
sudo rpi-update
sudo apt purge rpi-update
by DougieLawson
Tue Jul 09, 2019 11:21 am
Forum: Networking and servers
Topic: MQTT-SN over Bluetooth
Replies: 10
Views: 254

Re: MQTT-SN over Bluetooth

Make sure you are using up-to-date examples. Anything mentioning 'pand', for example, is too old. Also, please post your results. I think MQTT over Bluetooth would be of some interest. You need to draw the strong distinction between MQTT which uses TCP/IP and MQTT-SN (MQTT for sensor networks) whic...
by DougieLawson
Tue Jul 09, 2019 11:08 am
Forum: Troubleshooting
Topic: Network fails after rebooting but fine after shutting down
Replies: 66
Views: 1507

Re: Network fails after rebooting but fine after shutting down

The problem occurs when I reboot. The Pi fails to find the wired IP address and the boot process hangs. If I unplug the network cable and immediately plug it back in then the boot process continues and everything is normal again. Obviously unplugging/re-plugging the cable is not a great solution, e...
by DougieLawson
Tue Jul 09, 2019 11:01 am
Forum: Off topic discussion
Topic: How broken is the WWW?
Replies: 45
Views: 2043

Re: How broken is the WWW?

The sites that really annoy me are the ones that complain about me running browser ad blockers to save my bandwidth.
by DougieLawson
Tue Jul 09, 2019 10:59 am
Forum: Off topic discussion
Topic: Got too many raspberries?
Replies: 25
Views: 1423

Re: Got too many raspberries?

I've still got 17 running and one dead 2B (from my outdoor weather station).

I may go with the £20 3B+ to replace that one, although I'm concerned that the Weather Station HAT may shoot another RPi dead.
by DougieLawson
Tue Jul 09, 2019 10:37 am
Forum: Troubleshooting
Topic: I can´t boot from usb in pi 4
Replies: 74
Views: 4061

Re: I can´t boot from usb in pi 4

Rubbish. We did a lot of testing, internally and externally (and I am amazed there were no leaks) but when you sell 100k devices in a couple of weeks, suddenly a lot more stuff get attached, and a lot more bugs get found. This has happened for every Pi release. The HMDI bugs - fixed. Chromium playb...
by DougieLawson
Mon Jul 08, 2019 8:46 pm
Forum: Troubleshooting
Topic: RPi 4 cannot connect to WiFi
Replies: 11
Views: 286

Re: RPi 4 cannot connect to WiFi

Get rid of the key_mgmt line, it can break networking if it's wrong. The AP MUST use WPA or WPA2 (at least) and NOT WEP. The RPi4 can work with 2.4GHz or 5GHz have you got the SSID names correct? Does the GUI widget on the taskbar show the network? What do you get from iwlist scan command in an Lxte...
by DougieLawson
Mon Jul 08, 2019 8:42 pm
Forum: Troubleshooting
Topic: Sudo upgrade error
Replies: 1
Views: 150

Re: Sudo upgrade error

Your network is unreliable or Your local mirror is broken.

If the mirror is broken pick another that's local and update /etc/apt/sources.list and/or /etc/apt/sources.list.d/raspi.list with the web address for it.

https://www.raspbian.org/RaspbianMirrors
by DougieLawson
Mon Jul 08, 2019 8:17 pm
Forum: Off topic discussion
Topic: OMG - I can't believe I did this
Replies: 11
Views: 718

Re: OMG - I can't believe I did this

I have literally trashed all my media and my PI NFS boots. I did it to a mainframe filesystem once. They gave me UID=0 and I managed to do a rm -rf * in the root. The last failure (lost lots of stuff including photos) was done by my eldest son. He had some electricians test equipment and decided to...
by DougieLawson
Mon Jul 08, 2019 8:11 pm
Forum: Beginners
Topic: Eclipse remote connection refused
Replies: 4
Views: 125

Re: Eclipse remote connection refused

Connection refused has a few possible causes

1. Wrong IP address
2. Right IP address, wrong port
3. Right IP address, right port, server daemon not listening
by DougieLawson
Mon Jul 08, 2019 7:36 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Pi 1B: Deactivate all LEDs
Replies: 5
Views: 267

Re: Pi 1B: Deactivate all LEDs

Does your script need the GUI? Or does it use pure command line stuff?
Does your script use explict paths and filenames (eg. /home/pi/foo not ~/foo)?
by DougieLawson
Mon Jul 08, 2019 7:33 pm
Forum: Beginners
Topic: When NOOBS 3.1.1 update?
Replies: 4
Views: 308

Re: When NOOBS 3.1.1 update?

In this forum there is instructions how to fix that, but i want to wait when what ever causes this is updated, Raspbian?, and then install latest NOOBS/Raspbian so wizard update finishes correctly. As I said: there will be no NOOBS update that will fix your problem. A newer version will *reinstall*...
by DougieLawson
Mon Jul 08, 2019 7:29 pm
Forum: General discussion
Topic: Starting up
Replies: 14
Views: 450

Re: Starting up

Technocolour wrote:
Mon Jul 08, 2019 7:27 pm
What comes on to the screen?

A ranbow box thing?

Some raspberries?
The rainbow is the firmware loading
The raspberries are the Linux kernel loading

What's on your SDCard, is it latest Raspbian Buster or NOOBS 3.1.1 or something else?
by DougieLawson
Mon Jul 08, 2019 5:03 pm
Forum: Troubleshooting
Topic: Connection to NTP server
Replies: 3
Views: 99

Re: Connection to NTP server

They don't include NTP by default in Stretch or Buster.

sudo apt install ntp
sudo timedatectl set-ntp 1
ntpq -p -n


Then you can try connecting to localhost or 127.0.0.1 or 192.168.3.14 (ip address for your RPi)
by DougieLawson
Mon Jul 08, 2019 4:32 pm
Forum: Beginners
Topic: RPi Zero W - cannot access
Replies: 7
Views: 203

Re: RPi Zero W - cannot access

neilgl wrote:
Mon Jul 08, 2019 4:30 pm
And that wpa_supplicant seems to be missing

Code: Select all

	key_mgmt=WPA-PSK
You don't need that, and it can prevent the WiFi associating with the access point if you get it wrong. Let wpa_supplicant work it out automagically.
by DougieLawson
Mon Jul 08, 2019 12:19 pm
Forum: Troubleshooting
Topic: I can´t boot from usb in pi 4
Replies: 74
Views: 4061

Re: I can´t boot from usb in pi 4

And that's a right proper PITA.

gparted can't resize FAT32 partitions smaller than 256MB. So you have to trash it or convert to ext4 before you can tinker with the disk layout.

That's why I'm leaving my two model 3Bs that boot from WD hard drives till last for the Buster upgrades.
by DougieLawson
Mon Jul 08, 2019 12:14 pm
Forum: General discussion
Topic: Looking for a case for rb pi 3 + pir motion sensor
Replies: 19
Views: 327

Re: Looking for a case for rb pi 3 + pir motion sensor

That was the words I was looking for "aircraft mode". Powered on but useless. Whatever the power supply state the point of flight safe mode is supposed to be to avoid interference with aircraft systems (there are other views on motivations). So it seems a good starting assumption that the tool for ...
by DougieLawson
Mon Jul 08, 2019 11:42 am
Forum: Python
Topic: problem with python program
Replies: 10
Views: 332

Re: problem with python program

Do you have both python-rpi-gpio and python3-rpi-gpio installed.

It really would be better if you ditched python2 and stuck to python3.
by DougieLawson
Mon Jul 08, 2019 11:40 am
Forum: General discussion
Topic: Looking for a case for rb pi 3 + pir motion sensor
Replies: 19
Views: 327

Re: Looking for a case for rb pi 3 + pir motion sensor

That was the words I was looking for "aircraft mode". Powered on but useless.
by DougieLawson
Mon Jul 08, 2019 11:05 am
Forum: General discussion
Topic: Looking for a case for rb pi 3 + pir motion sensor
Replies: 19
Views: 327

Re: Looking for a case for rb pi 3 + pir motion sensor

PiGraham wrote:
Mon Jul 08, 2019 10:26 am
pcmanbob wrote:
Fri Jul 05, 2019 1:22 pm
I am not sure you can actually turn the wifi off on a pi.
Isn't that what rfkill does?
rfkill is a software switch. It disables the kernel driver. It has no effect on hardware (which remains powered up but useless).
by DougieLawson
Mon Jul 08, 2019 10:41 am
Forum: General discussion
Topic: use Pi 3B+ SD (Buster) in Pi 4 B?
Replies: 5
Views: 274

Re: use Pi 3B+ SD (Buster) in Pi 4 B?

An upgrade would also need rpi-update as the new bootcode/firmware isn't in Stretch.
by DougieLawson
Mon Jul 08, 2019 9:35 am
Forum: Beginners
Topic: Raspi Call Centre idea
Replies: 6
Views: 1087

Re: Raspi Call Centre idea

It was a bad idea three years ago. It is still a bad idea. Each organisation should run a local or off-shore (if you hate your staff) call centre. The walk-in laptop fixers is the thing that works best (at one of the major clients I do some work for). I had to visit them after a Win10 blue screen fa...
by DougieLawson
Mon Jul 08, 2019 9:29 am
Forum: Beginners
Topic: Starting shell script automatically when start up
Replies: 3
Views: 120

Re: Starting shell script automatically when start up

Search Google for "systemd service site:raspberrypi.org/forums" and you'll find hundreds of examples of how to do this stuff with systemd rather than sysvinit.
by DougieLawson
Mon Jul 08, 2019 9:26 am
Forum: General discussion
Topic: Update Error
Replies: 6
Views: 413

Re: Update Error

The pragmatic answer is upgrade to Buster on a new SDCard then move your programs & data over from the retired & unsupportable OS. Dougie. Please read the posts. This is happening if you already have Buster. Sorry I read it as Jessie. Buster updates were working ok for me yesterday when I was rebui...

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