Hostonly networking: comm between hostOS (Win7-64) and guestOS (CentOS6) + static-IP

[B Dutta]

My setup/config:

Host-system: Running Win 7 (64-bit Enterprise edition) absolutely latest
patches

Virtualbox: 64-bit rel 4.3.10 build 93012
Network config: Host-only network, NIC: Paravirtualized Host-only adapter

Guest-system: CentOS 6.4 (64-bit) stripped-down minimalistic server package
(we use it extensively on physical hardware without issues)

Within my guestOS, I see only "lo" (loopback) and "virbr0" (for the libvirt
based host-only network). "virbr0" has the host-only gateway-less subnet
"192.168.122.0/24".

Problem statement:

My reading of the documentation for host-only networking is that IP
communication between multiple guest VMs on the same host, is possible, and
also IP communication between host and guest VM's is possible. However, even
with ssh-daemon running/configured, using putty(ssh-client on Windows) to try
to login to guestVM on 192.168.122.100 (what was assigned to guest by DHCP),
doesn't seem to work.

Of course, I can create a 2nd interface (eth0) as NAT/bridged, but I wanted
to double-check if my assumption about capabilities of host-only network are
incorrect, about host <--> guestVM comm?

thanks,
BD

[Gregory Nowak]

Post by B Dutta
Host-system: Running Win 7 (64-bit Enterprise edition) absolutely latest
patches
Virtualbox: 64-bit rel 4.3.10 build 93012
Network config: Host-only network, NIC: Paravirtualized Host-only adapter
Guest-system: CentOS 6.4 (64-bit) stripped-down minimalistic server package
(we use it extensively on physical hardware without issues)
Within my guestOS, I see only "lo" (loopback) and "virbr0" (for the libvirt
based host-only network). "virbr0" has the host-only gateway-less subnet
"192.168.122.0/24".
My reading of the documentation for host-only networking is that IP
communication between multiple guest VMs on the same host, is possible, and
also IP communication between host and guest VM's is possible. However, even

This is correct as far as I know.

Post by B Dutta
with ssh-daemon running/configured, using putty(ssh-client on Windows) to try
to login to guestVM on 192.168.122.100 (what was assigned to guest by DHCP),
doesn't seem to work.

I would double check that. On my host, in host only networking, my
host gets 192.168.56.100, the first guest gets 192.168.56.101, the
second guest would get 192.168.56.102, and so on. What I'm saying is
that as far as I know, the dhcp server starts assigning addresses to
the guests one higher than what the host has. If I'm correct, then
your host should have an address of 192.168.122.99 based on what you
said above. If that's not the case, I would check your setup. You
could also try using ssh to 192.168.122.101 just for laughs. Of course
if I'm wrong, I'm sure someone else will correct me.

Post by B Dutta
Of course, I can create a 2nd interface (eth0) as NAT/bridged, but I wanted
to double-check if my assumption about capabilities of host-only network are
incorrect, about host <--> guestVM comm?

You should be able to have host and guest(s) talking to each other
using host only networking. You shouldn't need NAT/bridged unless you
want to give your guests access to the outside world.

Greg

[Gregory Nowak]

Post by Gregory Nowak
I would double check that. On my host, in host only networking, my
host gets 192.168.56.100, the first guest gets 192.168.56.101, the
second guest would get 192.168.56.102, and so on. What I'm saying is
that as far as I know, the dhcp server starts assigning addresses to
the guests one higher than what the host has. If I'm correct, then
your host should have an address of 192.168.122.99 based on what you
said above. If that's not the case, I would check your setup. You
could also try using ssh to 192.168.122.101 just for laughs. Of course
if I'm wrong, I'm sure someone else will correct me.

Major apologies, I'm correcting myself. My host gets assigned
192.168.56.1. My first guest does in fact get assigned
192.168.56.100. Again, I apologise for the confusion, it's been a long
day.

Greg