more cleanups to the vm document

Signed-off-by: Nico Schottelius <nico@kr.ethz.ch>
This commit is contained in:
Nico Schottelius 2010-10-31 22:59:17 +01:00
parent 1010091095
commit 6e0e1fb563

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@ -16,6 +16,38 @@ to operate, whereas others work with any Linux kernel.
Though some of them again need some configurations
to be turned on in the stock kernel.
### VM Installation
Depending on the hypervisor, there are different requirements
and methods for the installation:
* Installation can be done within the VM for completly isolated machines
* Installation must be done outside / on the host for systems without own kernel
Some hypervisors can boot from the network, whereas others just
create a very lightweight isolation and boot an installed system
only.
### Guest OS changes
Some hypervisors require changes to the virtual machines, to be able
to run successfully. Others allow a original OS version to be
installed.
### Network configuration
Whether the VM is attached to a bridge, a tun/tap device, treated
as a normal process, there may be a lot of different configurations.
Furthermore, firewall (masquerade/nat) configurations may be necessary.
Additionally, some of the hypervisors support dynamic allocation
of mac or even ip addresses.
### Templates
Some hypervisors support reusage of installations.
### Management
Most hypervisors contain some minor collection of utilities
@ -30,22 +62,38 @@ Typical issues are:
* Manual start/stop of VMs
* Listing of running / existing VMs
### Automated usage
Especially interesting for a sysadmin is, how easy a system can
be automated, which steps need to be taken to get a new image
or copy of an existing one. This aspect is one focus of this
document.
## Hypervisors
[[!table data="""
Name | Host Kernel
[QEMU](http://wiki.qemu.org/) | Original
[KVM](http://www.linux-kvm.org/) | Original w/KVM
[Lguest](http://lguest.ozlabs.org/) | Original w/Lguest
[Linux Containers](http://lxc.sourceforge.net/) | Original w/Containers
[Linux VServer](http://linux-vserver.org) | Own
[User Mode Linux](http://user-mode-linux.sourceforge.net/) | Original
[OpenVZ](http://wiki.openvz.org/Main_Page) | Own
[Virtualbox](http://www.virtualbox.org/) | Original+Modules
[VMWare](http://www.vmware.com/) | Original+Modules / Own
[Xen](http://www.xen.org/) | Own
Name | Host Kernel | Guest OS changes
[QEMU](http://wiki.qemu.org/) | Original | no
[KVM](http://www.linux-kvm.org/) | Original w/KVM | no
[Lguest](http://lguest.ozlabs.org/) | Original w/Lguest | ?
[Linux Containers](http://lxc.sourceforge.net/) | Original w/Containers | yes
[Linux VServer](http://linux-vserver.org) | Own | ?
[User Mode Linux](http://user-mode-linux.sourceforge.net/) | Original | ?
[OpenVZ](http://wiki.openvz.org/Main_Page) | Own | ?
[Virtualbox](http://www.virtualbox.org/) | Original+Modules | no
[VMWare](http://www.vmware.com/) | Original+Modules / Own | no
[Xen](http://www.xen.org/) | Own | ?
"""]]
### lxc
Some hints on lxc:
* Helper scripts existent (lxc-debian, lxc-fedora, ...)
* adjust init. change dev. do not run udev (why?)
* Root open in the filesystem
* No network specified = all from host accessible!
## Libraries / Frameworks
[[!table data="""
@ -54,64 +102,4 @@ Ganetti |
Libvirt |
"""]]
## Raw import of notes
The following notes I made some months ago, which will
be the basis for this article.
Try all of them and handle them via creature!
Installation
------------
From host like lxc.
From "inside" like KVM/QEMU/VMWare.
status
------
eth: ip addresses / mac / dhcp
### lxc
Not completly isolated. Linux only. Many changes to the guest os.
Some scripts existent (lxc-debian, lxc-fedora). The latter does
not work on debian.
lxc-debian mit cache (schlau)
no real hypervisor existent.
mac / ipv4 management missing => creature
adjust init. change dev. do not run udev (why?)
Root open in the filesystem. Nice. Quota?
Ressources are shared, if nothing else is specified.
=> network = all!
First installation - than virtualisation!
kvm
---
mac address,
ip address => dhcp???
Bootstrapping
-------------
how tos
different methods
which way for which vm-type
Network
-------
Always dhcp? Either on the vm-host or external.
Reason: Easy to configure. Scales dynamically.
How to handle bridges etc.? Independent of the os?
Reuse OS
[[!tag net unix]]