2 - Raspberry PI Community Projects

# xm list
Name ID Mem VCPUs State Time(s)
Domain-0 0 940 1 r----- 3896.9
# xm create testxen.cfg
Using config file "/etc/xen/testxen.cfg".
Started domain testxen (id=1)
# xm list
Name ID Mem VCPUs State Time(s)
Domain-0 0 873 1 r----- 3917.1
testxen 1 128 1 -b---- 3.7
CAUTION
Only one domU per image!
While it is of course possible to have several domU systems running in parallel,
they will all need to use their own image, since each domU is made to believe it
runs on its own hardware (apart from the small slice of the kernel that talks to
the hypervisor). In particular, it isn't possible for two domU systems running
simultaneously to share storage space. If the domU systems are not run at
the same time, it is however quite possible to reuse a single swap partition, or
the partition hosting the /home filesystem.
Note that the testxen domU uses real memory taken from the RAM that would otherwise be
available to the dom0, not simulated memory. Care should therefore be taken, when building a
server meant to host Xen instances, to provision the physical RAM accordingly.
Voilà! Our virtual machine is starting up. We can access it in one of two modes. The usual way
is to connect to it “remotely” through the network, as we would connect to a real machine;
this will usually require setting up either a DHCP server or some DNS configuration. The other
way, which may be the only way if the network configuration was incorrect, is to use the hvc0
console, with the xm console command:
# xm console testxen
[...]
Starting enhanced syslogd: rsyslogd.
Starting periodic command scheduler: cron.
Starting OpenBSD Secure Shell server: sshd.
Debian GNU/Linux 6.0 testxen hvc0
testxen login:
One can then open a session, just like one would do if sitting at the virtual machine's keyboard.
Detaching from this console is achieved through the Control+] key combination.
Chapter 12 — Advanced Administration
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