This was all done using a Raspberry Pi Zero. Much of this guide was pulled from the following resources:
All of the following tasks are performed while SSH'd into the Raspberry Pi.
Add the following to the bottom of /boot/config.txt (need to edit as sudo):
dtoverlay=dwc2
Add the following to the bottom of /etc/modules (need to edit as sudo):
dwc2
Run the following to halt the Raspberry Pi:
sudo halt
Now, we can power the Raspberry Pi using its USB port that's marked USB (rather than the one marked PWR IN). Here's a summary of the trade-offs:
You could plug the TV into the Pi Zero W USB port, not the PWR IN port, using a standard micro USB cable. The cable will both supply power from the TV and make the USB data connection. The disadvantage is that the TV must be switched on to supply power to the Pi. When someone turns the TV off with the remote, the Pi will also lose power, which can corrupt your SD card.
Alternatively, you can connect a separate, always-on power supply to the PWR IN port, and use a slightly modified micro USB cable to connect the TV to the USB port. The modification is to cut the red wire inside the micro USB cable. This protects the Pi from damage that could be caused by drawing power from two different power sources. The advantage of this method is that the Pi is powered independently from the TV. It will be available on the network even if the TV is off, and there is a reduced risk of sudden power loss and SD card corruption.
The Arlo Base Station will always be on, so powering the Raspberry Pi via the USB port it's plugged into will be fine. Once plugged in and powered on, we can SSH back into the Raspberry Pi.
To enable mass storage device mode, we need to create a large file to act as the storage medium on the SD card. This file will emulate the USB flash drive that the TV sees. The following instructions will make the virtual USB storage read-only from the Raspberry Pi's perspective, but write-able from the device it's plugged into.
The command below will create an empty 16 GB binary file (change the count=16384 argument if you want a different size). Note that this will be limited by the available free space on your SD card (check the Avail column in df -h), and it may take a few minutes to complete the setup:
sudo dd bs=1M if=/dev/zero of=/piusb.bin count=16384The command below will format the empty binary file created in Step 3.1 into the FAT32 format:
sudo mkdosfs /piusb.bin -F 32 -IFirst, we create a folder on which we can mount the file system:
sudo mkdir /mnt/usb_shareI originally tried using mount to get it to mount, but it didn't work properly (probably starting offset issue?), but kpartx was able to do it fine:
sudo kpartx -a /piusb.bin
sudo mount /dev/mapper/loop0p1 /mnt/usb_shareI added these .bashrc so they run on boot, and it worked fine.
We can now enable/disable USB mass storage device mode. You can also create an alias for each of the following commands for convenience.
The command below will enable USB mass storage device mode:
sudo modprobe g_mass_storage file=/piusb.bin stall=0 ro=0 removable=1I created an alias called usb_start for this one.
The command below will disable USB mass storage device mode:
sudo modprobe -r g_mass_storageI created an alias called usb_stop for this one.
The Arlo Base Station should now be able to see the Raspberry Pi's virtual disk as a USB device:
- Open the Arlo app
- Click "SmartHub / Base Station / Bridge"
- Click on the Base Station the Raspberry Pi is plugged into
- Click "Storage Settings"
- Click "USB Device 1"
- Click "FORMAT USB FLASH DRIVE" to format for use by your Arlo Base Station
Once this is complete, the Arlo Base Station should now be able to use the virtual disk in the Raspberry Pi.
In Raspberry Pi, the mounted folder won't automatically refresh as files are added. Thus, you need to periodically unmount and remount the folder:
sudo umount /mnt/usb_share
sudo mount /dev/mapper/loop0p1 /mnt/usb_shareI created an alias called usb_remount that peforms both of these. I also added a cron job to do this every minute by adding the following to root's crontab (sudo crontab -e):
* * * * * umount /mnt/usb_share && mount /dev/mapper/loop0p1 /mnt/usb_share
I ran into an issue where it would randomly stop saving videos, but usb_stop && usb_start would fix it. Thus, I added a cron job to check, every 30 minutes, if the timestamp of the most recent file is more than 30 minutes old, at which point it would automatically also perform usb_stop && usb_start (relies on my numlist tool in my tools repo):
*/30 * * * * delta=$(eval 'date +%s -r "$(ls -dt /mnt/usb_share/arlo/*/*.* | head -1)" | numlist -sub"$(date +%s)" | numlist -abs') && if [[ "$delta" -ge "1800" ]] ; then modprobe -r g_mass_storage && modprobe g_mass_storage file=/piusb.bin stall=0 ro=0 removable=1 ; fi
I installed Rclone as follows:
sudo -v ; curl https://rclone.org/install.sh | sudo bashBecause Rclone Google Drive authentication needs a web browser, I then installed it on my main desktop as well, and I configured a Google Drive remote in my Raspberry Pi's Rclone using the following remote setup guide:
https://rclone.org/remote_setup/
All Arlo recordings can be uploaded to Google Drive using the following Rclone command:
for f in $(ls -d /mnt/usb_share/arlo/* | grep -v "arlo/metadata") ; do rclone copy --progress "$f" drive_niemasd:"Security Cameras" ; doneI then added a cron job to copy all of the recordings to a Google Drive folder every minute by adding the following to my user's crontab (crontab -e), where COMMAND is the Rclone upload command above (I added a 5-second delay using sleep just in case it overlaps with the remounting cron job):
* * * * * sleep 5 && COMMAND
If a lot of videos get recorded, you might run into issues with the next cron job starting before the previous one finishes, resulting in the system getting clogged up with a bunch of simultaneous Rclone processes. As such, rather than starting a cron job every minute, it may be better to start it e.g. every 5 minutes:
*/5 * * * * sleep 5 && COMMAND