VirtualBox guest with Host Only and Bridged network interfaces

My CentOS guest has interfaces
- 192.168.100.102 - host-only adapter
- 192.168.0.105 - bridged adapter

If I run ifconfig on my Mac (which is running the hypervisor) I see it has the same subnet (192.168.0.0) as the guests bridged adapter. The host only adapter appears to be represented by a new interface in the listing called vboxnet0 with an ipaddress of 192.168.100.100. This means the Mac is directly connected to both subnets and therefore doesn't need to route.

The guest should be able to route to internet (if available) via bridged adapter so therefore the default gateway should be the same as the one the Mac uses, i.e when I'm at home this is the wireless router and when I'm mobile it's my phones hotspot router. These are on different subnets and my guest interface is hard coded for a class C 192.168.0.0 network, this is OK for my home but my phones hotspot has a network address of 192.168.43.0.  To work around this I've been changing the eth0 interface IP Address in /etc/sysconfig/network-scripts/ifcfg-eth0. I probably need to add another interface so that I'll have three in total (1 for host only and two bridged, 1 for the mobile subnet (192.168.43.0) and another for home wireless subnet 192.168.0.0).  Not sure how to configure the routing table to contain both but I'll work that out. Alternatively I could just configure the home wireless router to be on subnet 192.168.43.0 but that wouldn't be as interesting.

To add a default router manually (not sure how to make this permanent as /etc/defaultgateway doesn't seem to be working) I run.
route add default gw 192.168.0.1 eth0

I would normally use netstat -r to look at the routing table but it takes ages to display the last entry (the one I'm interested in) for some reason. I've found that ip route list is faster.

Setting the DNS Server is just a case if updating /etc/resolve.conf.

Shared folders in VirtualBox

Example using MacOSX host and CentOS guest

Install Guest Additions on the guest...
https://www.virtualbox.org/manual/ch04.html

From the host command line run...
VBoxManage sharedfolder add <VM name> --name <share name> --hostpath <host directory>

For example...
VBoxManage sharedfolder add CentOS6.4 --name myshare --hostpath /Users/clarkeb/automation

Now you have the host mapped to a shared device on the guest. Now you need to mount that device within the guest OS to a point on the file system

mount -t vboxsf  <share name>  <empty directory>

For example

mount -t vboxsf  myshare  /home/clarkeb/automation

VBoxManage common commands

VBoxManage list vms

VBoxManage list runningvms

VBoxManage list hdds (gets size of vdi)

VBoxManage showvminfo <vm name>

VBoxManage clonevm <existing vmname> --name <new vm name> --basefolder <path> --register --mode all

VBoxManage modifyvm <vm name> --ostype Linux

VBoxManage modifyvm <vm name> --memory 8192

VBoxManage modifyhd "<path to .vdi file>" --resize 32768

VBoxManage registervm “path to .vbox file”

VBoxManage startvm <vm name> --type headless

VBoxManage guestproperty enumerate <vm name> | grep IP

VBoxManage snapshot list <vm name>

VBoxManage snapshot <vm name> take <new snapshot name>

VBoxManage snapshot <vm name> restore <snapshot name>

VBoxManage controlvm <vm name> poweroff

VBoxManage controlvm <vm name> savestate