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raspberry

Fixing USB Problems Ubuntu Server on Raspberry 4

When trying to rung Ubunto Server on a Raspberry 4 with 4 GB RAM, you might end up with the same problem as me: USB is not working at all.

The cause is a kernel bug affecting 4 GB version of the Raspberry 4 Model B only. 1 and 2 GB versions are working quite fine.

The issue has been identified and it’s been found to be a kernel bug with a solution in the works that being tested. In the meantime, you can access to your Raspberry Pi 4 4GB USB ports by limiting the memory to 3GB in /boot/firmware/usercfg.txt […]

To limit the available RAM to 3 GB just add

total_mem=3072

to the usercfg.txt.

Link: https://www.cnx-software.com/2019/11/04/raspberry-pi-4-4gb-models-usb-ports-dont-work-on-ubuntu-19-10/

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hacks raspberry

Raspberry Pi – Setting a static IPv4 address

It run me mad, as I tried to change the IP address of my Raspberry to a static one. I changed literally everything in  /etc/network/interfaces and reloaded, restarted and reboot the device over and over.

iface eth0 inet static
address 192.168.0.207
netmask 255.255.255.0
network 192.168.0.0
broadcast 192.168.0.255
gateway 192.168.0.

As the above configuration did not help a lot, I figured out that based on the Raspberry model, you need to change settings on various places.

First run

cat /proc/cpuinfo

to determine you model. While getting something like

pi@raspberrypi:~ $ cat /proc/cpuinfo
processor    : 0
model name    : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS    : 2.00
Features    : half thumb fastmult vfp edsp java tls
CPU implementer    : 0x41
CPU architecture: 7
CPU variant    : 0x0
CPU part    : 0xb76
CPU revision    : 7

Hardware    : BCM2708
Revision    : 0004
Serial        : 000000004715b608

you need to use the hardware revision and

Model and Pi Revision 256MB Hardware Revision Code from cpuinfo
Model B Revision 1.0 256MB 0002
Model B Revision 1.0 + ECN0001 (no fuses, D14 removed) 256MB 0003
Model B Revision 2.0
Mounting holes
256MB 0004
0005
0006
Model A
Mounting holes
256MB 0007
0008
0009
Model B Revision 2.0
Mounting holes
512MB 000d
000e
000f
Model B+ 512MB 0010
Compute Module 512MB 0011
Model A+ 256MB 0012
Pi 2 Model B 1GB a01041 (Sony, UK)
a21041 (Embest, China)
PiZero 512MB 900092

Based on this information you need

Model a

Static IP addresses in /etc/network/interfaces is not the “prefered” way,as it is an old way and DHCPCD5 is installed.

Model b

Static IP addresses are configured in the /etc/dhcpcd.conf and it is  required that /etc/network/interfaces is set to manually.

iface eth0 inet manual

That’s all…

Categories
raspberry

Locating unknown Raspberry Pi device in your Network

Just as a quick hint, once you have set up a new Raspberry Pi device (or probably any other device) which you don’t know, simply run the arp command to find out about your neighborhood.

Running

arp -a

will make usage of the ARP protocol and give you some interesting information about some devices in your network.

arp -a

In my very case, I was told, the newly installed Raspberry Pi got the IPv4 address 192.168.0.82.