How to organize networking and virtual machines in KVM on Ubuntu 12?

Question

Asterisk

Recently, I had a question about choosing a virtualization scheme . As a result of my conclusions, I settled on KVM ( XEN
seemed more difficult to me at the startup stage) host network 192.168.0.xx with virtual machines network 192.168.122.xx) 3. to create a guest machine (I originally planned virt-install, but it didn’t install - it gave errors and I postponed it) installed virt-manager on the client machine and connect to the server to create a guest 4. created a guest machine, used a network and a 40 gig screw with LVM
everything seems to be up and running, but the question of connection arose. It is not convenient to connect using the graphic client all the time. found out that it is possible to use port forwarding with the key (hostfwd=tcp::2222-:22), but how to do it after creating the guest machine I could not find
further I am interested in the question of routing requests to sites (and planning the network as a whole host + virtual machine) which will lie in different virtual machines, until the only thing that comes to mind is installing nginx in the host system and rooting port 80 on the guest ones
and there is a question about the parameters of the virtual machines (how much RAM and hard space is better to use, or maybe even bring some together) for the following purposes
1. Telephony
2. mail and jabber
3. web for 5 unloaded sites on php + mysql
4. web for development - nginx + apache + php + mysql + postgresql + apc
5. SVN + GIT
6. Fileserver (although I still have no idea how to implement it better)

Answer 1

Virtual Desktop (VDI) won't solve the problem?
type SPICE (Simple Protocol for Independent Computing Environments); Ulteo Open Virtual Desktop ( OVD ) or Quality Virtual Desktop ( QVD )

Answer 2

It is not clear why you "set up the network in a bridge" and at the same time you have virtual machines on a different subnet. Usually the bridge is made so that the virtual machines are on the same subnet as the host