Blars

My experience with network-manager is it causes networks to shutdown and restart periodically. This was quite a while ago, so the bug may have been fixed. I don't let it on any of my computers. You may want to see if you can get network manager to leave your ethernet alone. ("apt-get remove --purge" is one way.) Note that the armbian developers seem to be network manager fans.

Overlay file system is NOT what you want, it requires the original media to be readable. I'd recommend a u-boot that handles net booting (if it exists) loaded to the on-board flash, then a network root and swap if needed. One system would require real media and the others a network connection to it.

Are you sure this is a problem with your system rather than a routing problem with your Internet provider? In the past, I have disabled IPV6 as a workaround for such routing problems: (Non-arm debian system.) sysctl net.ipv6.conf.all.disable_ipv6=1

Why don't you supply power via the GPIO connector?

Onewire does have limitations on bus capacitance and length. When using multiple sensors on one interface, it is best to not have stubs, wire to one sensor then the next rather than both from the pi. You are also more likely to need to power your sensors rather than have them just on the bus.

I'm not I2S expert, but IIRC it alternates between the left and right channels, so you may need to do some data manipulation to make it a single SPI channel.

Modprobe will load any required modules, insmod won't.

/var/log uses the "log2ram" filesystem, and /var/log.hdd is on your sd card. This is done to minimize writes to the sd card. So while they appear duplicated, I think only the most recent stuff is kept in ram.

On my new orange pi zero I hooked a pl2303 usb converter to the three serial pins and use "screen /dev/ttyUSB4 115200" to connect. This gives garbage on boot, with occasional strings of meaningful info like "Orange Pi" or "Debian". Same converter worked fine on my Raspberry Pi Zero. I'm suspecting the Orange Pi is just too fast and either the pl2303 or my Debian system can't keep up. Does anyone have the serial console working? Should I try a cp2102 instead, or maybe reconfigure to a slower speed? When I configured a DHCP server and hooked it up via ethernet, I can get in fine. Armbian 5.25 jessie, 3.4.113 kernel. 64GB sandisk Ultra plus uSD card, power from 3 amp DC-DC via 20cm cable to 13-pin connector. I'd use bigger cable for power but 4/0 doesn't fit in 2.54mm pins.

WS2812B when run at 5v require more than 3.3v for logic high. So a logic level converter is needed for reliable operation.

Sure. Just write a driver module that manipulates the proper bits in the setup registers, read the data sheet for your CPU and the kernel source code. The "confidential" H3 data sheet is on the sunxi web site. Apparently the H2 used on the opi zero is very close, but I have not found it's data sheet. This is not something I would recommend for beginner programmers.

You can use iptables to set up NAT routing. If you don't need NAT, "echo 1 > /proc/sys/net/ipv4/ip_forward" will turn on ipv4 routing. I've never set up bridging.

Network manager's default behavior is to look for networks to connect to, killing long-running ssh sessions to "scan" for other wireless networks, etc. It may be possible to tell it not to, but if you don't want the obnoxious behavior the easy way to get rid of it is to uninstall it. Configuring via /etc/network/interfaces will do exactly what you tell it to and no more. If you want to scan for networks, you can do it manually. It may be harder for beginners to configure their network properly, but reliable networks are important to me.

Why would you want armel anyway? It's only for old hardware that can't support armhf, (v4t to v6) and the upcoming Debian release will be its last.

Problems have been reported with the network manager in Debian Sid on some networks, independent of hardware. Apparently it does random MAC assignment. I've always found "apt-get remove --purge" to fix network mangler problems.

On Debian, raid software isn't installed by default. Try "sudo apt-get install mdadm". (I have not yet received my Orange Pi, so I have not tried Armbian.)

Strange HDMI problems can be caused by differing ground levels. The video signals are differential, but the control ones aren't. In my case, running an extra ground wire fixed the problem, there was a 2v DC offset between the two.