The symptoms: after resuming my Macbook, my SSH connection to the VM is unresponsive. Switching to the VirtualBox display window, I can see from NetworkManager that the network is disconnected and that /etc/resolv.conf lists zero nameservers. Then the network is re-establishing for about 15-30 seconds. After becoming re-established, the guest can reach Internet IPs, but DNS resolution is broken since /etc/resolv.conf now has 127.0.0.1 as the only nameserver.
I don't believe this has always happened - I started noticing it happening a couple months back.
My questions:
1. What's going on with the disconnection and reconnection delay? Slightly annoying to have to wait for SSH to come back.
2. What's going on with the nameserver and how do I fix it? My workaround is to manually change 127.0.0.1 to e.g. 8.8.8.8 in /etc/resolv.conf.
Here are some details from the guest:
Code: Select all
$ uname -a
Linux yang-vbox-ubuntu 3.5.0-41-generic #64~precise1-Ubuntu SMP Thu Sep 12 16:50:04 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 12.04.3 LTS
Release: 12.04
Codename: precise
$ ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 08:00:27:69:20:88 brd ff:ff:ff:ff:ff:ff
inet 10.0.2.15/24 brd 10.0.2.255 scope global eth0
inet6 fe80::a00:27ff:fe69:2088/64 scope link
valid_lft forever preferred_lft forever
$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 08:00:27:69:20:88 brd ff:ff:ff:ff:ff:ff
$ cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 127.0.0.1
$ less /var/log/syslog
...
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): carrier now ON (device state 20)
Oct 22 16:52:25 yang-vbox-ubuntu kernel: [474262.748760] e1000: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
Oct 22 16:52:25 yang-vbox-ubuntu kernel: [474262.749423] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Auto-activating connection 'Wired connection 1'.
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) starting connection 'Wired connection 1'
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled...
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started...
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled...
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete.
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting...
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0]
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful.
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled.
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete.
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started...
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0]
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds)
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> dhclient started with pid 1967
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Beginning IP6 addrconf.
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete.
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: Internet Systems Consortium DHCP Client 4.1-ESV-R4
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: Copyright 2004-2011 Internet Systems Consortium.
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: All rights reserved.
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: For info, please visit https://www.isc.org/software/dhcp/
Oct 22 16:52:25 yang-vbox-ubuntu dhclient:
Oct 22 16:52:25 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): DHCPv4 state changed nbi -> preinit
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: Listening on LPF/eth0/08:00:27:69:20:88
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: Sending on LPF/eth0/08:00:27:69:20:88
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: Sending on Socket/fallback
Oct 22 16:52:25 yang-vbox-ubuntu dhclient: DHCPREQUEST of 10.0.2.15 on eth0 to 255.255.255.255 port 67
Oct 22 16:52:27 yang-vbox-ubuntu avahi-daemon[533]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::a00:27ff:fe69:2088.
Oct 22 16:52:27 yang-vbox-ubuntu avahi-daemon[533]: New relevant interface eth0.IPv6 for mDNS.
Oct 22 16:52:27 yang-vbox-ubuntu avahi-daemon[533]: Registering new address record for fe80::a00:27ff:fe69:2088 on eth0.*.
Oct 22 16:52:28 yang-vbox-ubuntu dhclient: DHCPREQUEST of 10.0.2.15 on eth0 to 255.255.255.255 port 67
Oct 22 16:52:33 yang-vbox-ubuntu dhclient: DHCPREQUEST of 10.0.2.15 on eth0 to 255.255.255.255 port 67
Oct 22 16:52:40 yang-vbox-ubuntu dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 3
Oct 22 16:52:40 yang-vbox-ubuntu dhclient: DHCPREQUEST of 10.0.2.15 on eth0 to 255.255.255.255 port 67
Oct 22 16:52:40 yang-vbox-ubuntu dhclient: DHCPOFFER of 10.0.2.15 from 10.0.2.2
Oct 22 16:52:40 yang-vbox-ubuntu dhclient: DHCPACK of 10.0.2.15 from 10.0.2.2
Oct 22 16:52:40 yang-vbox-ubuntu dhclient: bound to 10.0.2.15 -- renewal in 36515 seconds.
Oct 22 16:52:40 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): DHCPv4 state changed preinit -> bound
Oct 22 16:52:40 yang-vbox-ubuntu NetworkManager[753]: <info> address 10.0.2.15
Oct 22 16:52:40 yang-vbox-ubuntu NetworkManager[753]: <info> prefix 24 (255.255.255.0)
Oct 22 16:52:40 yang-vbox-ubuntu NetworkManager[753]: <info> gateway 10.0.2.2
Oct 22 16:52:40 yang-vbox-ubuntu NetworkManager[753]: <info> nameserver '10.0.2.3'
Oct 22 16:52:40 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Configure Commit) scheduled...
Oct 22 16:52:40 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) started...
Oct 22 16:52:40 yang-vbox-ubuntu avahi-daemon[533]: Joining mDNS multicast group on interface eth0.IPv4 with address 10.0.2.15.
Oct 22 16:52:40 yang-vbox-ubuntu avahi-daemon[533]: New relevant interface eth0.IPv4 for mDNS.
Oct 22 16:52:40 yang-vbox-ubuntu avahi-daemon[533]: Registering new address record for 10.0.2.15 on eth0.IPv4.
Oct 22 16:52:41 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): writing resolv.conf to /sbin/resolvconf
Oct 22 16:52:41 yang-vbox-ubuntu dnsmasq[939]: setting upstream servers from DBus
Oct 22 16:52:41 yang-vbox-ubuntu dnsmasq[939]: using nameserver 10.0.2.3#53
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): device state change: ip-config -> activated (reason 'none') [70 100 0]
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> Policy set 'Wired connection 1' (eth0) as default for IPv4 routing and DNS.
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) successful, device activated.
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) complete.
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> (eth0): IP6 addrconf timed out or failed.
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled...
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) started...
Oct 22 16:52:52 yang-vbox-ubuntu NetworkManager[753]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) complete.
Oct 22 16:52:52 yang-vbox-ubuntu dbus[500]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper)
Oct 22 16:52:52 yang-vbox-ubuntu dbus[500]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Oct 22 16:53:42 yang-vbox-ubuntu ntpdate[2048]: Can't find host ntp.ubuntu.com: Name or service not known (-2)
Oct 22 16:53:42 yang-vbox-ubuntu ntpdate[2048]: no servers can be used, exiting
Code: Select all
$ ifconfig
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
options=3<RXCSUM,TXCSUM>
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
inet 127.0.0.1 netmask 0xff000000
inet6 ::1 prefixlen 128
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
ether 20:c9:d0:89:f1:ab
inet6 fe80::22c9:d0ff:fe89:f1ab%en0 prefixlen 64 scopeid 0x4
inet 10.66.224.133 netmask 0xffffff00 broadcast 10.66.224.255
media: autoselect
status: active
p2p0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 2304
ether 02:c9:d0:89:f1:ab
media: autoselect
status: inactive
$ cat /etc/resolv.conf
#
# Mac OS X Notice
#
# This file is not used by the host name and address resolution
# or the DNS query routing mechanisms used by most processes on
# this Mac OS X system.
#
# This file is automatically generated.
#
nameserver 8.8.8.8
nameserver 156.154.70.1
https://www.virtualbox.org/ticket/421
https://www.virtualbox.org/ticket/1470
https://www.virtualbox.org/ticket/3847
https://www.virtualbox.org/ticket/10864
Any help would be greatly appreciated. Thanks in advance.