# Troubleshooting

We're happy to help with any problems or questions that arise when using Brewblox. You can reach us on the forum (opens new window).

Our first reply often consists of the same handful of questions. To save you some time, you may want to run through this checklist first.

  • Is your system and firmware up-to-date? You can run brewblox-ctl update to check, or find the latest release date in https://brewblox.netlify.com/user/release_notes.html
  • brewblox-ctl log generates all kinds of logs and diagnostic data for us to look at. It will also create a termbin.com link. You can copy that URL in your post.
  • In the UI sidebar, bottom left corner there is a "bug" button. Click here, and choose "Export API errors to file". Please attach this file to your post.
  • If your Spark service page is working, it may be useful to include your Blocks. You can export them by clicking on the "Actions" button in the top right corner of the service page, and then choosing "Import/Export Blocks". Please attach the generated file to your post.

# Known issues / workarounds

Installation fails with "E: Package 'python3-venv' has no installation candidate"

For example:

Package python3-venv is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'python3-venv' has no installation candidate

The python3-venv package is found in the universe Apt repository (opens new window). If the installation fails with the above error, it is likely you need to enable universe packages by running:

sudo add-apt-repository universe
sudo apt update --fix-missing

brewblox-ctl keeps asking to re-install shared libraries

If you made an alias for "brewblox-ctl", it may disrupt the use of the new unified brewblox-ctl application.

Remove the alias, reload your shell, and try again.

Graphs and widgets don't show on iOS

There is a bug on iOS where Websockets always fail to connect if the backend is using a self-signed SSL certificate. Brewblox uses Websockets to stream graph data, and by default uses self-signed SSL certificates.

When using Brewblox in a local network, the simplest solution is to switch to HTTP when using iOS. The UI will automatically suggest this if it fails to make a Websocket connection when using iOS + HTTPS.

Do note that its suggested redirect is not perfect: if you are using non-standard ports for HTTP/HTTPS, you will be redirected to an invalid page. In that case, manually navigate to http://address:port.

During updates, my Pi hangs while creating services

The most likely cause for this is overflow in swap memory.

Especially if you have a Pi 3 or 4, you may see improvements when disabling swap memory altogether:

sudo dphys-swapfile swapoff
sudo dphys-swapfile uninstall
sudo update-rc.d dphys-swapfile remove
sudo rm -f /etc/init.d/dphys-swapfile

sudo service dphys-swapfile stop
sudo systemctl disable dphys-swapfile.service
sudo reboot

My Pi suddenly reboots

This is often caused by underpowered chargers, especially if the Pi reboots while pulling or starting Docker images. For more information, see the official power requirements page (opens new window).

After a crash, I get a "port already allocated" error

Example error
pi@raspberrypi:~/brewblox$ brewblox-ctl up
Starting brewblox_redis_1 …
Starting brewblox_spark-one_1 …
Starting brewblox_eventbus_1 …
Starting brewblox_ui_1 …
Starting brewblox_influx_1 …
Starting brewblox_redis_1 … done
Starting brewblox_spark-one_1 … done
Starting brewblox_eventbus_1 … done
Starting brewblox_ui_1 … done
Starting brewblox_influx_1 … done
Starting brewblox_history_1 … done
d340b): Bind for 0.0.0.0:443 failed: port is already allocated

ERROR: for traefik Cannot start service traefik: driver failed programming external connec
y on endpoint brewblox_traefik_1 (10330d14f76b330f33ad4aa17947be57c452f3b2f32521fe08a4ed9ca
0b): Bind for 0.0.0.0:443 failed: port is already allocated
ERROR: Encountered errors while bringing up the project.
Command ‘docker-compose up -d --remove-orphans’ returned non-zero exit status 1.

This is caused by leftover zombie processes created by Docker. To forcibly remove them, run:

brewblox-ctl kill --zombies

My Pi is no longer accessible as [HOSTNAME].local

The Pi itself publishes the [HOSTNAME].local DNS record. Sometimes the DNS record is still active when the name service start.

To reset, access the Pi by using the IP address or [HOSTNAME]-2.local (eg. raspberrypi-2.local), and restart the name service by running:

sudo service avahi-daemon restart

# Frequently asked questions

No Spark controller detected (in service, or in brewblox-ctl)

For reference, you can find the full guide on connection settings guide here.

Is the Spark screen completely white, or completely black (but status LED is on)?

This happens when the bootloader is outdated or not present. To flash the bootloader, run:

brewblox-ctl particle -c flash-bootloader

The Spark screen should show six boxes on a dark background.

USB: is the cable connected?

Never hurts to check.

USB: what is the output from the lsusb command?

lsusb lists currently connected USB devices.

Example output:

pi@washberry:~ $ lsusb
Bus 001 Device 005: ID 2b04:c008
Bus 001 Device 004: ID 0781:5583 SanDisk Corp. Ultra Fit
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. SMC9514 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

The xxxx:xxxx section after ID is the relevant bit. This is the VID:PID (Vendor ID, Product ID) of each device.

The VID:PID for a Spark 2 is 2b04:c006.
The VID:PID for a Spark 3 is 2b04:c008.

In the example, Bus 001 Device 005 is a Spark 3.

If your Spark is connected, but does not show up in this list, check again with a different USB cable.

Wifi: is the Spark connected to Wifi?

If the Spark LCD does not show an IP address, connect to it using USB, and configure Wifi:

  • Open the Brewblox UI
  • Go to the Spark service page
  • Go to the actions menu in the top right corner
  • Choose "Configure Wifi"

Wifi: is the Spark accessible from your computer and the Raspberry Pi?

  • Can you visit the Spark IP in your browser? It should show a short placeholder message.
  • If you run brewblox-ctl http get <SPARK_IP>, do you see the html for the placeholder message?

If the answer to either is no, your Spark and Pi are likely using different subnets in your home network. Check your router configuration to allow them to communicate.

If the answer to all questions is yes, but the service still can't find your Spark, it may be a problem with mDNS.

By default, we use multicast DNS (opens new window) to discover Sparks that are not connected over USB. In most - but not all - routers, mDNS is enabled by default. Check your router configuration for settings related to multicast DNS.

If you can't solve the problem in your router settings, it may be preferable to skip discovery, and add --device-host=SPARK_IP to your docker-compose.yml file. You can find the syntax in the connection settings guide.

When doing so, it is advised to assign a fixed IP address to the Spark in your router settings. (Also called "static DHCP lease").

How do I display temperature values in Fahrenheit?

In the UI, go to the Admin page. This can be accessed at the top of the sidebar.

Here, go to General settings -> Temperature units, and select Fahrenheit.

History data field names include the unit. If you have active graphs, you will need to reconfigure them to use the Fahrenheit values.

Why can removed or renamed blocks still be selected in the Graph Widget settings?

History data is not changed when a block changes name. After a name change, the service simply starts publishing data under the new name.

The old name will disappear from the Graph widget settings 24 hours after the block is removed or renamed.

Units are part of the field name. For 24 hours after changing units from Celsius to Fahrenheit, you'll see both spark-one/block/value[degC] and spark-one/block/value[degF] in the Graph settings.

Last Updated: 11/11/2021, 11:24:41 AM