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From Chiradeep Vittal <>
Subject Re: Guest network without virtual router
Date Wed, 13 Mar 2013 00:13:46 GMT
In the first go-around, not sure what do you mean DNS didn't work. I
assume you could ping ? The cloudstack DHCP systemvm will
forward DNS requests that it cannot resolve with its own /etc/hosts to the
'zone' DNS server.

In the second go-around it is probably expected behavior, but I cannot say
for sure. CloudStack implements anti-spoofing at the hypervisor level, so
if the packet coming out of the VM does not have a source ip/mac it
doesn't know about, it instructs the hypervisor to drop it. In this case
since the ip was assigned by a DHCP server not controlled by CloudStack
this will most likely result in a dropped packet.
You could try logging into the hypervisor and execute
ebtables -F

On 3/12/13 4:48 AM, "Wei Leong" <> wrote:

>Nope, basic networking the second time too.
>On Mar 12, 2013, at 1:25 AM, "Chiradeep Vittal"
><> wrote:
>> Is the second go-around using advanced networking?
>> On 3/10/13 1:54 PM, "Wei Leong" <> wrote:
>>> It seems I am having a lot of trouble setting up even the simplest of
>>> cloudstack networking configurations.
>>> A quick background on my setup:
>>> The kvm host is part of a network of machines that gets their IPs from
>>> the router. I intend to set up cloudstack to extend our development
>>> infrastructure, VMs in the cloud will function just like physical
>>> machines on the network and depend on the router for dhcp and dns. My
>>> intention is to have cloudstack manage the provisioning of VMs and
>>> provide analysis of the cloud resources (memory, storage etc). Pretty
>>> straightforward stuff here.
>>> My initial setup actually worked out ok - I created a zone with basic
>>> networking (DefaultSharedNetworkOfferingWithSGService) and guest VMs
>>> assigned IPs according to the range I specified. The VMs had access to
>>> the internet and were able to connect to other machines on the network,
>>> but DNS did not work. My sys admin was also curious about whether the
>>> virtual router was leasing out IPs to physical machines on the network,
>>> could this happen? Is is better for hosts to have static IP addresses?
>>> I then scratched the initial setup and created a new network offering
>>> without DHCP, and used that instead. For this configuration, no virtual
>>> router came up, VMs seem to be getting IPs from the external router,
>>> none of them can connect to physical machines on the network/the
>>> I feel like i'm close to getting the right configuration, and might
>>> be missing a small detail. I'm not ready to give up yet, even though
>>> out of ideas at this point. Any suggestions/help is much appreciated.
>>> Thanks for reading!
>>> Wei
>>> On Mar 7, 2013, at 6:22 PM, Bryan Whitehead
>>> <<>> wrote:
>>> Create a new network offering without DHCP. After you do that create a
>>> guest network using that network offering / vlan.
>>> On Thu, Mar 7, 2013 at 8:58 AM, Wei Leong
>>> Is there an easy way from the UI to create a network without using the
>>> virtual router? I'm running configured cloudstack with basic networking
>>> and
>>> the cloudstack server sits in our network that already has a
>>> setup. I would like my guest VMs to just that instead of the virtual
>>> router.
>>> According to this blog it is possible but only through the API, is
>>> an alternative?
>>> k-without-a-virtual-router/

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