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My instance can ping the outside world, why doesn't a browser connect? [closed]

asked 2014-09-04 07:31:38 -0500

capsali gravatar image

updated 2014-09-04 12:50:05 -0500

nickchase gravatar image


As the title says, i'm having problem with browsing from instances.

I can ping the outside world, either by ip or by name.

The problem is when i try to use the browser. Only two addresses work : the default IE homepage, and bing search. Everything else hangs and i don't receive any errors. It just sits at connecting or receiving data.

I can't help but think that this is a security group matter but i don't know what to activate. I tried opening some ports with no luck.

Also i can even make a pptp vpn in windows instance and connect to it from the outside world. This was simple because i knew i had to open port 1723 and add port number 47(GRE).

Can anybody tell me how i can make this work? Is anybody else troubled by this?

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Closed for the following reason the question is answered, right answer was accepted by capsali
close date 2014-09-04 15:10:08.005507


Are you running GRE system with MTU 1500 at VM's eth0 ?
Then run ifconfig eth0 mtu 1454 up.

dbaxps gravatar imagedbaxps ( 2014-09-04 07:38:57 -0500 )edit

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answered 2014-09-04 07:40:58 -0500

dbaxps gravatar image

updated 2014-09-04 08:18:01 -0500

Are you running GRE system with MTU 1500 at VM's eth0 ?
Then run ifconfig eth0 mtu 1454 up.

System tuning

[root@dfw02 neutron(keystone_admin)]$ cat dhcp_agent.ini | grep -v ^# | grep -v ^$
interface_driver = neutron.agent.linux.interface.OVSInterfaceDriver
handle_internal_only_routers = TRUE
external_network_bridge = br-ex
ovs_use_veth = True
use_namespaces = True
dnsmasq_config_file = /etc/neutron/dnsmasq.conf

[root@dfw02 neutron(keystone_admin)]$ cat  dnsmasq.conf
log-facility = /var/log/neutron/dnsmasq.log
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I'm not sure i understand!

If u are refering to set the /etc/neutron/dnsmasq-neutron.conf with the value dhcp-option-force=26,1454 following documentation, i did. Should i set the mtu to the compute host and network host or in the VM?

capsali gravatar imagecapsali ( 2014-09-04 07:51:08 -0500 )edit

Post report ifconfig on your VM .

dbaxps gravatar imagedbaxps ( 2014-09-04 07:54:09 -0500 )edit

it's a windows 2012 instance :) I set the mtu manually in the VM but no luck.

capsali gravatar imagecapsali ( 2014-09-04 07:55:18 -0500 )edit

Post ipconfig report.

dbaxps gravatar imagedbaxps ( 2014-09-04 07:59:28 -0500 )edit

Launch standard ubuntu cloud image and make sure you can ssh to it via ssh keypair.
- trusty-server-cloudimg-amd64-disk1.img Then run :
$ curl

dbaxps gravatar imagedbaxps ( 2014-09-04 08:03:30 -0500 )edit

answered 2014-09-04 12:40:38 -0500

alexpilotti gravatar image

We added recently MTU handling in cloudbase-init, so if you are running a recent version it will automatically pick up the MTU from the DHCP server.

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Asked: 2014-09-04 07:31:38 -0500

Seen: 847 times

Last updated: Sep 04 '14