DHCPCD5 on BegaleBone Black

[Mike Brandon]

Long story short, I am refactoring an application I had originally written for Raspbian. One of the features is the ability to modify the devices network settings (either use DHCP or set a static IP).

When refactoring this for the Begalebone, I was running into weird issues that I assume were happening because of conman. After many hours I stumbled into installing DHCPCD5.

I then added eth0 to  NetworkInterfaceBlacklist in /etc/conman/main.conf

I modified /etc/network/interfaces to be 

# interfaces(5) file used by ifup(8) and ifdown(8)

# Please note that this file is written to be used with dhcpcd
# For static IP, consult /etc/dhcpcd.conf and 'man dhcpcd.conf'

# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d

auto lo
iface lo inet loopback

Then, programatically, I was able to switch between dhcp and static settings as I expected with my application.

I then noticed in /var/log/syslog that I was getting a TON of logged messages related to can0 and can1. 

I added can0 and can1 to conman/main.conf NetworkInterfaceBlacklist

I added denyinterfaces can0 can1 in /etc/dhcpcd.conf

I thought I had this resolved after the two steems above but it seems that is not the case.

What else can I do to keep this behavior from occurring? The issue is causing a noticeable lag when SSH'ed into my beaglebone or using the web interface I am running on it. Not to mention the file space it is consuming.

If DHCPCD is not a viable candidate, how can I get more predictable behavior out of conman? (Issues I was running into included changing settings in /network/interfaces did not alsways respond as expected, issues with configuring a fallback static IP when DHCP failed, etc.)

BTW I am running the Debian 8.7 IoT image (need it in order to run mongodb on the beaglebone)

[Mike Brandon]

Here is a glimpse at what is getting logged in syslog

Nov 21 14:00:22 beaglebone dhcpcd[1402]: can0: up_interface: Invalid argument

Nov 21 14:00:22 beaglebone dhcpcd[1402]: can0: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:22 beaglebone connmand[900]: can0 {newlink} index 5 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone kernel: [   72.979573] c_can_platform 481d0000.can can1: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   72.986511] c_can_platform 481d0000.can can1: failed to open can device

Nov 21 14:00:23 beaglebone connmand[900]: can0 {newlink} index 5 operstate 2 <DOWN>

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: set_mtu: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: up_interface: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:23 beaglebone connmand[900]: can1 {newlink} index 6 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone connmand[900]: can1 {newlink} index 6 operstate 2 <DOWN>

Nov 21 14:00:23 beaglebone kernel: [   73.031073] c_can_platform 481cc000.can can0: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   73.037980] c_can_platform 481cc000.can can0: failed to open can device

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: set_mtu: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: up_interface: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:23 beaglebone kernel: [   73.077959] c_can_platform 481d0000.can can1: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   73.084876] c_can_platform 481d0000.can can1: failed to open can device

Nov 21 14:00:23 beaglebone connmand[900]: can0 {newlink} index 5 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone connmand[900]: can0 {newlink} index 5 operstate 2 <DOWN>

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: set_mtu: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: up_interface: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:23 beaglebone kernel: [   73.125759] c_can_platform 481cc000.can can0: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   73.132708] c_can_platform 481cc000.can can0: failed to open can device

Nov 21 14:00:23 beaglebone connmand[900]: can1 {newlink} index 6 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone connmand[900]: can1 {newlink} index 6 operstate 2 <DOWN>

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: set_mtu: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: up_interface: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:23 beaglebone connmand[900]: can0 {newlink} index 5 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone connmand[900]: can0 {newlink} index 5 operstate 2 <DOWN>

Nov 21 14:00:23 beaglebone kernel: [   73.198296] c_can_platform 481d0000.can can1: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   73.205158] c_can_platform 481d0000.can can1: failed to open can device

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: set_mtu: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: up_interface: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:23 beaglebone kernel: [   73.247552] c_can_platform 481cc000.can can0: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   73.254472] c_can_platform 481cc000.can can0: failed to open can device

Nov 21 14:00:23 beaglebone connmand[900]: can1 {newlink} index 6 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone connmand[900]: can1 {newlink} index 6 operstate 2 <DOWN>

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: set_mtu: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: up_interface: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:23 beaglebone kernel: [   73.318195] c_can_platform 481d0000.can can1: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   73.325025] c_can_platform 481d0000.can can1: failed to open can device

Nov 21 14:00:23 beaglebone connmand[900]: can0 {newlink} index 5 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone connmand[900]: can0 {newlink} index 5 operstate 2 <DOWN>

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can0: set_mtu: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: up_interface: Invalid argument

Nov 21 14:00:23 beaglebone dhcpcd[1402]: can1: unsupported interface type 00, falling back to ethernet

Nov 21 14:00:23 beaglebone connmand[900]: can1 {newlink} index 6 address 00:00:00:00:00:00 mtu 16

Nov 21 14:00:23 beaglebone kernel: [   73.419087] c_can_platform 481cc000.can can0: bit-timing not yet defined

Nov 21 14:00:23 beaglebone kernel: [   73.425987] c_can_platform 481cc000.can can0: failed to open can device