ifconfig dummy0 : Device not found
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
ifupdown (Ubuntu) |
Invalid
|
Low
|
Unassigned | ||
kmod (Ubuntu) |
Invalid
|
Undecided
|
Unassigned | ||
net-tools (Ubuntu) |
Invalid
|
Low
|
Unassigned | ||
systemd (Ubuntu) |
Invalid
|
Undecided
|
Unassigned |
Bug Description
Desired behavior:
The ifconfig command should be able to deal with the
dummy device. This worked fine until recently.
Observed behavior:
:; ifconfig dummy0
dummy0: error fetching interface information: Device not found
This problem appeared when I upgraded to bionic.
Highly informative workaround:
:; ip link add dummy0 type dummy
That command works, and makes the problem go away permanently.
The ifconfig command works fine after that.
The ifup and ifdown commands also work fine after that.
For convenient debugging, you can use the command:
:; ip link del dummy0 type dummy
which makes the problem come back.
You can also experiment with dummy1 et cetera.
Package ownership issues:
Compare: https:/
That report was filed against ippusbxd, which is almost certainly
not the relevant package.
For that matter, I have no idea whether the root cause is in the
net-tools package or the kernel networking stack. All I know is
the ip command plays nicely with the kernel while the ifconfig
command does not.
Notes:
The kernel module for the dummy interface is preloaded in
all situations described here. That's not the issue.
An apport file is attached, to describe the environment.
Also, since you asked:
:; apt-cache policy net-tools
net-tools:
Installed: 1.60-26ubuntu1
Candidate: 1.60-26ubuntu1
Version table:
*** 1.60-26ubuntu1 500
500 http://
100 /var/lib/
:; lsb_release -rd
Description: Ubuntu 16.04.6 LTS
Release: 16.04
I put the attached file in if-pre- up.d/dummy- workaround
to make my system work reliably.