Beaglebone Black DNS bug

Embedded Linux Discussions
1

Hello,

I’ve run into an unexpected issue that seems so simple to solve yet I have been unable to find a solution.

ping localhost fails with “ping: unknown host localhost” whenever the ethernet cable is unplugged.

the loopback is up: ping 127.0.0.1 succeeds.

Something about bringing eth0 up starts a dns server that is otherwise inactive.

Has anyone ran into this and aware of a solution or work-around?

Unfortunately I’m tied to an old version of debian, 7.9 and can’t upgrade due to legacy drivers that also rely on localhost rather than 127.0.0.1 for some socket connections.

I have tweaked the configuration of /etc/hosts and /etc/resolv.conf to no avail, and tried static, manual, and hotplug variants of the interfaces, but this has not helped either.

Thanks,

JeffC

2

What’s in your hostfile?

cat /etc/hosts

Sorry, Debian 7.x really does not get tested anymore…

Regards,

3

I realize the 7.x is far from being supported, so I appreciate that you even responded.

I tested from a fresh install of the 7.9 image posted at the beagleboard latest images page.

I believe I also found the issue: in 7.9, the permissions on /etc/hosts and /etc/hostname default to 600 while in 7.8 and 7.11 they default to 644. After making this adjustment, ping localhost succeeds even when an ethernet cable is not plugged in.

Thanks,
JeffC

4

awesome @jeff.campbell ! Looking back, this may have been when i fixed it: chroot: carpet bomb files to root:root · RobertCNelson/omap-image-builder@586c447 · GitHub 2015…

Regards,