instance cannot ping outside world with domain name

asked 2015-06-25 01:36:37 -0600

JohnMar gravatar image

updated 2015-06-25 01:57:43 -0600

uts9 gravatar image

Hello all,

I am a beginner to openstack and have been struggling with this for weeks now. I have installed OpenStack Juno on Ubuntu 14.04 servers following the install guide on I have three nodes and I am running nova-network with one controller and two compute nodes.

Every thing is working fine and I can SSH to my instances but I can't ping the outside world with a domain name. I tried to modify dnsmasq using


and my instance has this on resolv.conf and whenever i reset my dns server this way, i am able to ping outside two or three times and it stops resolving. I really have no idea why this is happening. Do i have to add something to iptables?

I have the following on nova-network-POSTROUTING

ACCEPT all --
ACCEPT all -- ! ctstate DNAT

where is my flat network and is my compute management ip

Please help and thanks for ur time.

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Could you please check your Security Group settings?. Usually I check iptables settings (POSTROUTING etc) in case of DNS issue.

uts9 gravatar imageuts9 ( 2015-06-25 01:42:41 -0600 )edit

Hi, I have modified my question, thanks

JohnMar gravatar imageJohnMar ( 2015-06-25 01:53:55 -0600 )edit

Please check this post.

uts9 gravatar imageuts9 ( 2015-06-25 02:08:47 -0600 )edit

1 answer

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answered 2015-06-26 03:34:28 -0600

RAHUL1603 gravatar image

Check whether it is a problem of name resolution or pinging. dig various site such, facebook, etc if you get a corresponding IP then it is issue with networking. If you are able to ping continuously and name resolution is not working (dig) then it is a problem of dnsmasq.

If dnsmasq problem then try these steps --

create a blank file and point to that file in compute nodes nova.conf (dnsmasq_config_file=/etc/dnsmasq-nova.conf) restart all the nova services, restart dnsmasq service and it should work now.

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Asked: 2015-06-25 01:36:37 -0600

Seen: 590 times

Last updated: Jun 26 '15