CentOS - Mar 2018 - VirtualBox on CentOS 7 with bridged network not working

I've installed VirtualBox v5.2 on a CentOS 7.4 machine, but VMs set up 
with bridged networking can not 'see' past the VirtualBox host machine

i.e. the VM can ping the host and vice versa, but the VM can not ping 
anything else and other machines on the same subnet can't ping the VM

There are no firewall rules configured on the 7.4 host and selinux is 
disabled

I have a similar set up on a CentOS 6.9 host, where everything works as 
expected

Googling doesn't show up any similar issues, so I guess I'm missing 
something on the host machine

Does anyone have any idea what could be the issue?

Thanks

James Pearson

On Thu, Mar 15, 2018 at 03:47:42PM +0000, James Pearson
wrote:
> I've installed VirtualBox v5.2 on a CentOS 7.4 machine, but VMs set up 
> with bridged networking can not 'see' past the VirtualBox host
machine
> 
> i.e. the VM can ping the host and vice versa, but the VM can not ping 
> anything else and other machines on the same subnet can't ping the VM
I hate to be the first to say "works for me", but it does! :)

I have (or have had) many VMs in Virtualbox, both Windoze and various
flavors of Linux, as well as one or two other things. I always set
them up as bridged and they "just" work.

Can't think of what might cause it, but you might want to look at
/var/log/messages, etc., on both the guest and the host. Make sure
the vbox kernel module(s) is(are) installed. I don't think the vbox
tools for the client would have anything to do with this, but it won't
hurt to check that they are properly installed.

Good luck!

Fred
-- 
---- Fred Smith -- fredex at fcshome.stoneham.ma.us
-----------------------------
  "And he will be called Wonderful Counselor, Mighty God, Everlasting
Father,
  Prince of Peace. Of the increase of his government there will be no end. He 
 will reign on David's throne and over his kingdom, establishing and
upholding
      it with justice and righteousness from that time on and forever."
------------------------------- Isaiah 9:7 (niv) ------------------------------

On Thu, Mar 15, 2018 at 10:47 AM, James Pearson <james-p at
moving-picture.com>
wrote:
> Googling doesn't show up any similar issues, so I guess I'm missing
> something on the host machine
>
> Does anyone have any idea what could be the issue?
>
What kind of hardware? There can be issues with trying to bridge across a
WiFi connection and you may need to use NAT. On wired on a server I've had
issues where the network had multiple VLANs allowed directly to the
ethernet adapter and I had to configure where the VLAN was being tagged for
the VMs. A bit more fleshed out description of your hardware and network
set up would help out.

James Pearson wrote:
> 
> I've installed VirtualBox v5.2 on a CentOS 7.4 machine, but VMs set up
> with bridged networking can not 'see' past the VirtualBox host
machine
> 
> i.e. the VM can ping the host and vice versa, but the VM can not ping
> anything else and other machines on the same subnet can't ping the VM
> 
> There are no firewall rules configured on the 7.4 host and selinux is
> disabled
> 
> I have a similar set up on a CentOS 6.9 host, where everything works as
> expected
> 
> Googling doesn't show up any similar issues, so I guess I'm missing
> something on the host machine
> 
> Does anyone have any idea what could be the issue?
I've manged to 'solve' the problem - which wasn't anything to do
with
CentOS 7 ... the host running CentOS 7 was patched into a switch with 
MAC access control enabled - as were the two other CentOS 7 boxes I 
tried - whereas the CentOS 6 host(s) I used had no MAC access control 
enabled

Just wish it hadn't taken me nearly a day to work that out :-)

Sorry for the noise

James Pearson