Ask Your Question
0

Sometimes instances launch with more than one IP

asked 2016-11-15 13:12:24 -0500

xdaxdb gravatar image

Sometimes when I launch an instance it will show as having more than one IP. When I log in to the instance it only has one interface, eth0 (and lo) and there is only one IP address configured on it. The second IP address is nowhere to be found inside the instance, I only see it on the dashboard.

It seems like this becomes more common when launching multiple instances at the same time, but I have had it happen when launching a single instance too.

What could cause this? I can't find any error messages, presumably because the instance launched successfully.

edit retag flag offensive close merge delete
add a comment

2 answers

Sort by ยป oldest newest most voted
1

answered 2016-11-16 09:20:32 -0500

eblock gravatar image

From my experience, this happened when an instance was about to fail or the first attempt to boot happened on a "wrong" hypervisor. I have two (xen) hypervisors and if I tried to launch an instance from an image without correct properties, I could see that nova tried to launch that instance on both hypervisors. But sometimes the instance booted successfully and Horizon showed two ip addresses, but I also could find only one of them within the instance. If the instance launched successfully, you can simply detach the wrong interface/address via Horizon. It's no real explanation, just sharing my experience.

edit flag offensive delete link more

Comments

It was funny I was looking at the instance from the "admin" view and didn't see an option to remove interfaces. I was able to just remove it from the "project" view. Simple.

xdaxdb gravatar imagexdaxdb ( 2016-11-16 13:53:18 -0500 )edit
add a comment
1

answered 2016-11-15 22:19:28 -0500

bcollins gravatar image

i had this occur when i had a few different things going on:

try checking your plugin configurations (openvswitch) try ensuring dhcp is not running on your physical versus what's running in openstack.

I know I had conflicting ip addresses / multiple addresses when i had a provider network with dhcp enabled and colliding dhcp scopes with physical network and openstack

edit flag offensive delete link more
add a comment

Get to know Ask OpenStack

Resources for moderators

Question Tools

2 followers

subscribe to rss feed

Stats

Asked: 2016-11-15 13:12:24 -0500

Seen: 200 times

Last updated: Nov 16 '16

Related questions

Packets not leaving compute host

How to configure the DHCP server so that it can assign IP to VMs?

Horizon shows that my instance gets IP address,but actually it does not!

DHCP packets lost between VM and dnsmasq

Failed to bind port

Instances didn't get an ip from neutron dhcp agent

DHCP is not answering on OVS

Neutron ML2: vCenter VM does not get static DHCP from Neutron dhcp-agent (Icehouse)

neutron dhcp issues

Openstack conjure-up compute instances not getting ip addresses