Re: [Qemu-discuss] About how to connect from guest "10.0.2.15" to remote "192.168.1.xx"

[Qi Zhang]

I have a web server on my host
and I try  wget http://10.0.2.2, it works
but if I try on the LAN interface wget http://192.168.1.10, it does
not, I have already added the default router as 10.0.2.2

Could you help to figure out what's missing part on my kernel
configure or QEMU command line?

Thanks

On Wed, Feb 15, 2012 at 8:56 AM, Mike Lovell <address@hidden> wrote:
> it does match. i just now ran a test and i was able to ping 10.0.2.2 but not
> able to ping anything else. despite not being able to ping outside the
> 10.0.2.0/24 network, i was able to do the wget i listed before and
> connectivity to the rest of the world works. don't expect ping to be a good
> test when using user networking and talking to things outside of 10.0.2.2.
>
> mike
>
>
> On 02/14/2012 05:30 PM, Qi Zhang wrote:
>>
>> Mike:
>>        My guest can ping to host with the address 10.0.2.2 but just
>> can't ping to host's LAN interface 192.168.1.10, does that match with
>> your point?
>> Thanks
>> Zhang Qi
>>
>> On Wed, Feb 15, 2012 at 1:33 AM, Mike Lovell<address@hidden>  wrote:
>>>
>>> On 02/14/2012 02:21 AM, Qi Zhang wrote:
>>>>
>>>> Hi There:
>>>>
>>>>         I'm trying to use QEMU to emulate a simple Linux Guest for
>>>> some specific task
>>>>         I have download/compile the Linux 3.2.5 kernel and busybox
>>>> 1.19.4 and successfully make the guest system running after some
>>>> simple setup.
>>>>         Also the guest system can mount host NFS after I set the eth0
>>>> IP to 10.0.2.15.  (mount -t nfs 10.0.2.2:/xxx/xxx /tmp)
>>>>
>>>>         Now the host system is also connect to a LAN (192.168.1.10),
>>>> and there is application running on the guest system, who want to talk
>>>> to another server on the LAN (192.168.1.8)
>>>>         but guest (10.0.2.15) can't ping to the remote server
>>>> (192.168.1.8),
>>>>         I have manually add the default gateway as 10.0.2.2, that
>>>> still not work.
>>>>         Destination     Gateway         Genmask         Flags Metric
>>>> Ref    Use Iface
>>>>         0.0.0.0         10.0.2.2        0.0.0.0         UG    0      0
>>>>        0 eth0
>>>>         10.0.0.0        0.0.0.0         255.0.0.0       U     0      0
>>>>        0 eth0
>>>>
>>>>         Can anybody help me to figure it out?
>>>>         Wish the solution is not about use the tap/bridge solution,
>>>>         I was lack of related network knowledge and the only thing I
>>>> know is use QEMU "user net" is something similar as "NAT" option in
>>>> virtual box,
>>>>         though when use NAT the host can't ping to guest, but the
>>>> guest can ping to everywhere and there is no bridge I think
>>>>
>>>>         BTW:
>>>>         my host system is Ubuntu 11.10 and the command to start the QEMU
>>>> is
>>>>         "qemu-system-x86_64 -kernel arch/x86/boot/bzImage -boot d
>>>> -append 'console=ttyS0, 115200' -nographic -net nic -net user"
>>>
>>>
>>> if i remember correctly, the user networking doesn't support ping or
>>> various
>>> other ICMP messages. it uses a limited IP stack directly in the qemu
>>> process
>>> and doesn't support everything that the kernel's IP stack supports. after
>>> you set the ip address and default gateway in the guest, try connecting
>>> to
>>> the service you want to talk to or try putting a web page through wget. i
>>> frequently just use `wget http://google.com/` to test network
>>> connectivity
>>> when using user networking.
>>>
>>> mike
>>>
>