[SOLVED] Container "eth0" down after boot

[jstuyts]

Hi,

I can't get a (fully up-to-date) Debian 8 container to bring eth0 up after boot. If I enter the container I can bring eth0 up manually without issues.

The container was created using:

pct create 105 /var/lib/vz/template/cache/debian-8.0-standard_8.0-1_amd64.tar.gz \
    -description "Proxmox DHCP" \
    -hostname pvedhcp \
    -pool infrastructure \
    -cpulimit 1 \
    -cpuunits 1024 \
    -memory 256 \
    -swap 64 \
    -net0 "name=eth0,bridge=vmbr0,tag=2,ip=dhcp,ip6=dhcp" \
    -rootfs zfs_first-hdd-partial:2 \
    -onboot 1

Here is /etc/network/interfaces that is generated by Proxmox VE:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet6 dhcp

iface eth0 inet dhcp

Here is the output of a session showing the issue:

root@dev-joy-division:~# pct start 105

root@dev-joy-division:~# pct enter 105

root@pvedhcp:~# ifconfig
eth0      Link encap:Ethernet  HWaddr 32:61:65:62:64:33
          inet6 addr: fe80::3061:65ff:fe62:6433/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:8 errors:0 dropped:0 overruns:0 frame:0
          TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:648 (648.0 B)  TX bytes:798 (798.0 B)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

root@pvedhcp:~# ifdown eth0
ifdown: interface eth0 not configured

root@pvedhcp:~# ifup eth0
Internet Systems Consortium DHCP Client 4.3.1
Copyright 2004-2014 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/

Listening on LPF/eth0/32:61:65:62:64:33
Sending on   LPF/eth0/32:61:65:62:64:33
Sending on   Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6
DHCPREQUEST on eth0 to 255.255.255.255 port 67
DHCPOFFER from 192.168.0.1
DHCPACK from 192.168.0.1
bound to 192.168.0.100 -- renewal in 37221 seconds.

root@pvedhcp:~# ifconfig
eth0      Link encap:Ethernet  HWaddr 32:61:65:62:64:33
          inet addr:192.168.0.100  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::3061:65ff:fe62:6433/64 Scope:Link
          inet6 addr: fd98:b6a5:55:2:ffff::4a0d/64 Scope:Global
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:15 errors:0 dropped:0 overruns:0 frame:0
          TX packets:20 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1850 (1.8 KiB)  TX bytes:2434 (2.3 KiB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

 

[jstuyts]

Well, this is embarrassing. It seems I should check my configuration using a hex dump from now on. Apparently /etc/network/interfaces contained a character that prevented it from being read correctly, which prevented /etc/init.d/networking from bringing up the interfaces.

I found this out by deleting /etc/network/interfaces and rebooting. After the container came back up, eth0 was up. I checked the file and only the settings for eth0 were there. Adding the settings for lo again, did not break things this time.