Attachment #2903 for bug #20811




unterschiedliche Vor- und Nachteile. KVM beispielsweise benötigt
zwingend CPU-Virtualisierungunterstützung während Xen auch (eingeschränkt)
Systeme ohne Unterstützung durch die Hardware virtualisieren kann. Zu
Details können die Webseiten der beiden Projekte konsultiert werden:
\ucsURL{http://www.linux-kvm.org/} und \ucsURL{http://www.xen.org/}.

Zusätzlich sollte bei der Installation der Virtualisierungsserver die
Architektur beachtet werden. Nur auf UCS-Systemen, die mit der
amd64-Architektur installiert sind, können auch 64 Bit-Systeme
virtualisiert werden.

\section{UMC-Modul}

  Verzeichnis} zur Verfügung. Dieser liegt auf den Virtualisierungs-Servern unterhalb
des Verzeichnisses \ucsURL{/var/lib/libvirt/images/} (weitere
Informationen zur Verwaltung von Speicherbereichen sind im \href{http://wiki.univention.de/index.php?title=UVMM_Quickstart}{Wiki} zu
finden).
Zum Einbinden als CDROM-Laufwerke können ISO-Images ebenfalls in diese Verzeichnis kopiert werden.
Anschließend stehen sie sofort zur
Verfügung und können mit neuen Laufwerken verknüpft werden.

Werden Laufwerke für eine neu zu installierende Instanz definiert,


Ist eine virtuelle Instanz mit dem Assistenten erfolgreich angelegt
worden, zeigt das UMC-Modul sofort die Übersicht zu der neuen Instanz
an. Die Einstellungen einer Instanz sind in mehrere Bereiche aufgeteilt
(Abbildung \ref{pic:uvmm-domain-settings}):

\begin{itemize}


Die Grundeinstellungen einer virtuellen Instanz sind unter \ucsMenuEntry{Einstellungen}
zu finden. Dort gibt es folgende Felder, die nur verändert
werden können, wenn die virtuelle Instanz ausgeschaltet ist und keine Sicherungspunkte angelegt sind:

\begin{description}
\item[Name] definiert den Namen der virtuellen Instanz. Dieser muss

  installierten Betriebssystems genutzt werden
\item[Architektur] legt die Architektur der emulierten Hardware
  fest. Dabei ist zu beachten, dass nur auf Virtualisierungs-Servern
  der Architektur amd64 virtuelle 64 Bit-Instanzen angelegt werden
  können. Dies wird vom UMC-Modul auf i386-Systemen auch unterbunden.
\item[Anzahl der CPUs] definiert wieviele virtuelle CPUs der virtuellen
  Instanz zugeteilt werden.




following section on the description of the functions.

\subsection{Creating a virtual instance}
\label{uvmm:instanz:erstellen}

The \ucsUMC{} module has a wizard for creating virtual instances,
which can be used to create a virtual machine in just a few steps. In
the first step a profile is selected which specifies some of the basic
settings for the virtual machine (e.g., a name prefix, number of CPUs,
RAM and whether the direct access per VNC should be activated). As can be
seen in Figure \ref{pic:uvmm-instance-wizard}, there are profiles for
different operating systems. Depending on the operating system, some
parameters for the virtualisation are defined in the UVMM profile. For


\ucsGraphicsRef[0.95]{Assistant for creating a virtual machine}{../doku/uvmm/abbildungen/uvmm-instance-wizard_en.png}{uvmm-instance-wizard}

The existing UVMM profiles are stored in the LDAP directory and can
also be edited there. The profiles can be found in
the \ucsMenuEntry{Navigation} section of \ucsUDM{} in the
container \emph{cn=Profiles,cn=Virtual Machine Manager}.
Additional profiles which have been adapted to suit the respective environment can also be added there.
respective environment.

Once basic configuration of the virtual machine is complete, the drives
are defined.
Subsequently existing drives can be removed and new drives can be created.
When adding drives, image files are
created for virtual hard drives or existing files are linked to the
hard drives or CDROM drives. 

Hard drive images can be administrated in two ways on KVM systems; by
default images are saved in the \ucsName{Extended format (qcow2)}
format.
This format supports Copy-on-write which means that changes do not overwrite the original version, but store new versions in different locations.
The internal references are updated to allow both access to the original and the new version.
This technique is a prerequisite for efficiently managing snapshots of virtual machines.
systems of virtual machines.

Alternatively, you can also access a hard drive image
in \ucsName{Simple format (raw)}. Snapshots can only be created when using
hard drive images in the \ucsName{Extended format}.

For Xen systems only the \ucsName{Simple format} is available.

These image files are stored in so-called
storage pools.
By default each virtualisation server already provides a storage pool with the name \emph{Local directory}.
This can be found on the virtualisation servers in
the \ucsURL{/var/lib/libvirt/images/} directory (further information
on the management of storage pools can be found in the \href{http://wiki.univention.de/index.php?title=UVMM_Quickstart}{Wiki}).
For mounting CDROM drives ISO images can also be copied into this directory.
They are then immediately available and can be linked with new
drives.

For new virtual machines the order of creating new drives is important.
It must be ensured that it is possible to boot from the CDROM drive.
The UVMM profile specifies the boot order for fully-virtualised instances in advance.
For paravirtualised instances, the first device listed is always used as the boot device.
This can be changed subsequently in the settings section.
subsequently in the settings.

\subsection{Modifying virtual machines}
\label{uvmm-instance-edit}
When a virtual instance is successfully created with the wizard, the
UMC module displays an overview of the new instance immediately. The
settings of a virtual machine are divided into multiple sections
(Figure \ref{pic:uvmm-domain-settings}):

\begin{itemize}
\item Snapshots
\item Drives
\item Settings
\item Extended settings


\ucsGraphicsRef[0.95]{Settings of a virtual machine}{../doku/uvmm/abbildungen/uvmm-domain-settings_en.png}{uvmm-domain-settings}

The \ucsMenuEntry{Drives} section contains a list of the defined drives
with the type, image file and size as well as the assigned storage
pool. At the end of each line there is a \ucsMenuEntry{Delete}
button, which can be used to remove the drive (the image file can

images can also be created for hard drives. These are created as
sparse files with the specified size, i.e., these files only grow when
they are used and then up to the maximally specified size and thus
initially require only minimal disk space.

The basic settings of a virtual instance can be found in the \ucsMenuEntry{Settings} section.
This includes the following fields
which can only be changed if the virtual instance is turned off and no snapshots are used.

\begin{description}
\item[Name] defines the name of the virtual machine. This does not
have to be the same as the name of the host in the LDAP directory.
\item[Operating System] can contain a description of the virtual instance or of the operating system used.
\item[Architecture] specifies the architecture of the emulated
hardware. It must be noted that virtual 64 bit machines can only be
created on virtualisation servers using the amd64 architecture.
This setting is not shown on i386 systems.
\item[Number of CPUs] defines how many virtual CPUs are assigned to
the virtual instance.
\item[MAC address] specifies the hardware address of the network
interface. If this field is left empty, a random value is
automatically generated.
\item[Memory] specifies the size of the system memory.
\item[Interface] defines the interface used for the bridge on the
physical server. This is usually \emph{eth0}, which is also the
default setting.
\end{description}

In the last section \emph{Extended settings}, you can find the following
attributes:

\begin{description}

the virtual machine searches the drives for bootable media. This
setting is only available for fully-virtualised instances. For
paravirtualised instances it is defined by the order of the drives.
\item[Direct access] defines whether VNC access to the virtual
machine is available. If the option is activated, the UMC module
can be used to start a VNC program directly. The VNC URL is displayed in a tool tip.
A Java VNC program is used for this in the default setting.
By switching the \ucsUCRV{uvmm/umc/vnc} to the value of \emph{external}, an external
program can be used instead.
This requires the web browser on the workstation computer to be configured properly to handle the URI scheme \ucsURL{vnc://}.
\item[Available globally] defines whether the VNC remote access is
also possible from remote systems. If the option is not activated, the
VNC session can only be accessed from the virtualisation server.

\subsection{Removing virtual machines}
Virtual instances no longer required can be deleted along with all
their hard drives and ISO images. The images to be deleted can be
selected from a list. It must be noted that ISO images and sometimes
also hard drive images may be used by multiple instances.
They only should be deleted when the are no longer used by any instance.

\subsection{Starting/stopping/suspending virtual machines}
Instances created via UVMM are turned off in the initial status. This
status can changed in the overview of the respective virtualisation server
in the respective list entry or in the overview of the virtual
machine itself. In the latter case, there is
an \ucsMenuEntry{Operations} section, in which the status can be
set. The following possibilities exist:

\begin{description}
\item[Start] starts the virtual machine.
\item[Stop] turns the virtual machine off. It must be noted that
the operating system is not turned off first, i.e., it should be
compared with turning off a computer by pulling the power plug.
\item[Pause] assigns the instance no further CPU time. This still
uses the working memory on the physical host, but the instance itself
is paused.

\end{description}

\subsection{Migrating virtual machines}
A further function which can be found in the \emph{Operations} section
of the overview is the possibility of a migrating a virtual machine
to another virtualisation server. This works with both paused and running
instances (live migration).

For migration to work it must be noted that the images of the mounted
hard drives and CDROM drive must be available in the same location on both
physical servers. This can be archived, for example, by storing the images
in a central storage system.

\subsection{Managing snapshots}

UVMM offers the possibility to save the contents of the main and
hard drive memory of a virtual machine in \ucsName{Snapshots}.
This allows the administrator to revert the virtual instance back to these snapshots
at a later point in time, which makes them useful as a ``safety net''
when installing software updates.

Snapshots can only be used with KVM instances which access all their hard
drive images in Qcow2 format. All snapshots are stored using
copy-on-write (see \ref{uvmm:instanz:erstellen}) directly in
the hard drive image file. 

The administration is performed in the \ucsMenuEntry{Snapshots} section in the
settings of a virtual machine.

\ucsMenuEntry{Create new snapshot} can be used to create a
snapshot with the name of your choice, e.g., \emph{DC Master before
update to UCS 2.4-2}.
In addition to the description the time is saved when the snapshot is created.
The following list shows all available snapshots ordered reverse-chronologically.
\ucsMenuEntry{Revert} can be used to return the machine to
an earlier snapshot and \ucsMenuEntry{Delete} can be used to
remove a snapshot.





Return to bug 20811

Lines 112-122 Link Here

(-)doku/uvmm/uvmm_en.tex (-67 / +68 lines)
112	following section on the description of the functions.	112	following section on the description of the functions.
113		113
114	\subsection{Creating a virtual instance}	114	\subsection{Creating a virtual instance}
		115	\label{uvmm:instanz:erstellen}
		116
115	The \ucsUMC{} module has a wizard for creating virtual instances,	117	The \ucsUMC{} module has a wizard for creating virtual instances,
116	which can be used to create a virtual machine in just a few steps. In	118	which can be used to create a virtual machine in just a few steps. In
117	the first step a profile is selected which specifies some of the basic	119	the first step a profile is selected which specifies some of the basic
118	settings for the virtual machine (e.g., a name prefix, no. of CPUs,	120	settings for the virtual machine (e.g., a name prefix, number of CPUs,
119	RAM and whether the access per VNC should be activated). As can be	121	RAM and whether the direct access per VNC should be activated). As can be
120	seen in Figure \ref{pic:uvmm-instance-wizard}, there are profiles for	122	seen in Figure \ref{pic:uvmm-instance-wizard}, there are profiles for
121	different operating systems. Depending on the operating system, some	123	different operating systems. Depending on the operating system, some
122	parameters for the virtualisation are defined in the UVMM profile. For	124	parameters for the virtualisation are defined in the UVMM profile. For
Lines 125-182 Link Here
125		127
126	\ucsGraphicsRef[0.95]{Assistant for creating a virtual machine}{../doku/uvmm/abbildungen/uvmm-instance-wizard_en.png}{uvmm-instance-wizard}	128	\ucsGraphicsRef[0.95]{Assistant for creating a virtual machine}{../doku/uvmm/abbildungen/uvmm-instance-wizard_en.png}{uvmm-instance-wizard}
127		129
128	The existing UVMM profiles are read out of the LDAP directory and can	130	The existing UVMM profiles are stored in the LDAP directory and can
129	also be edited there. The profiles can be found in	131	also be edited there. The profiles can be found in
130	the \ucsMenuEntry{Navigation} section of \ucsUDM{} in the	132	the \ucsMenuEntry{Navigation} section of \ucsUDM{} in the
131	container \emph{cn=Profiles,cn=Virtual Machine Manager}. Additional	133	container \emph{cn=Profiles,cn=Virtual Machine Manager}.
132	ones can also be added here that have been adapted to suit the	134	Additional profiles which have been adapted to suit the respective environment can also be added there.
133	respective environment.
134		135
135	Once the basic configuration of the virtual machine is complete, the drives	136	Once basic configuration of the virtual machine is complete, the drives
136	are defined. These can also be adapted subsequently just like the	137	are defined.
137	configuration of the machine. When adding drives, image files are	138	Subsequently existing drives can be removed and new drives can be created.
		139	When adding drives, image files are
138	created for virtual hard drives or existing files are linked to the	140	created for virtual hard drives or existing files are linked to the
139	hard drives or CDROM drives.	141	hard drives or CDROM drives.
140		142
141	Hard drive images can be administrated in two ways on KVM systems; by	143	Hard drive images can be administrated in two ways on KVM systems; by
142	default images are saved in the \ucsName{Qemu copy-on-write 2}	144	default images are saved in the \ucsName{Extended format (qcow2)}
143	format. Copy-on-write means that a change in a file system does not	145	format.
144	directly change the actual file, but rather stores a new version in a	146	This format supports Copy-on-write which means that changes do not overwrite the original version, but store new versions in different locations.
145	different place. The internal references of the file administration	147	The internal references are updated to allow both access to the original and the new version.
146	are then updated. This allows you to create snapshots of the file	148	This technique is a prerequisite for efficiently managing snapshots of virtual machines.
147	systems of virtual machines.
148		149
149	Alternatively, you can also access a hard drive image	150	Alternatively, you can also access a hard drive image
150	in \ucsName{Raw format}. Snapshots can only be created when using	151	in \ucsName{Simple format (raw)}. Snapshots can only be created when using
151	hard drive images in \ucsName{Qemu copy-on-write 2} format.	152	hard drive images in the \ucsName{Extended format}.
152		153
153	Only the \ucsName{Raw format} is available on Xen systems.	154	For Xen systems only the \ucsName{Simple format} is available.
154		155
155	These image files are stored in so-called	156	These image files are stored in so-called
156	storage pools. Each virtualisation server already provides a storage	157	storage pools.
157	pool with the name \emph{Local directory} in the default	158	By default each virtualisation server already provides a storage pool with the name \emph{Local directory}.
158	setting. This can be found on the virtualisation servers in	159	This can be found on the virtualisation servers in
159	the \ucsName{/var/lib/libvirt/images} directory (further information	160	the \ucsURL{/var/lib/libvirt/images/} directory (further information
160	on the management of storage pools can be found in Wiki). ISO images	161	on the management of storage pools can be found in the \href{http://wiki.univention.de/index.php?title=UVMM_Quickstart}{Wiki}).
161	can also be copied into this directory for mounting with CDROM	162	For mounting CDROM drives ISO images can also be copied into this directory.
162	drives. They are then immediately available and can be linked with new	163	They are then immediately available and can be linked with new
163	drives.	164	drives.
164		165
165	If drives are defined for an virtual machine to be installed from new, it	166	For new virtual machines the order of creating new drives is important.
166	must be ensured that it is possible to boot from the CDROM drive. The	167	It must be ensured that it is possible to boot from the CDROM drive.
167	UVMM profile specifies the boot order for the fully-virtualised	168	The UVMM profile specifies the boot order for fully-virtualised instances in advance.
168	instances in advance. For the paravirtualised instances, it is defined	169	For paravirtualised instances, the first device listed is always used as the boot device.
169	by the order on the definition of the drives and can be adapted	170	This can be changed subsequently in the settings section.
170	subsequently in the settings.
171		171
172	\subsection{Modifying virtual machines}	172	\subsection{Modifying virtual machines}
173	\label{uvmm-instance-edit}	173	\label{uvmm-instance-edit}
174	When a virtual instance is successfully created with the wizard, the	174	When a virtual instance is successfully created with the wizard, the
175	UMC module displays an overview of the new instance immediately. The	175	UMC module displays an overview of the new instance immediately. The
176	settings of a virtual machine are divided into three areas	176	settings of a virtual machine are divided into multiple sections
177	(Figure \ref{pic:uvmm-domain-settings}):	177	(Figure \ref{pic:uvmm-domain-settings}):
178		178
179	\begin{itemize}	179	\begin{itemize}
		180	\item Snapshots
180	\item Drives	181	\item Drives
181	\item Settings	182	\item Settings
182	\item Extended settings	183	\item Extended settings
Lines 184-190 Link Here
184		185
185	\ucsGraphicsRef[0.95]{Settings of a virtual machine}{../doku/uvmm/abbildungen/uvmm-domain-settings_en.png}{uvmm-domain-settings}	186	\ucsGraphicsRef[0.95]{Settings of a virtual machine}{../doku/uvmm/abbildungen/uvmm-domain-settings_en.png}{uvmm-domain-settings}
186		187
187	The \ucsMenuEntry{Drives} menu contains a list of the defined drives	188	The \ucsMenuEntry{Drives} section contains a list of the defined drives
188	with the type, image file and size as well as the assigned storage	189	with the type, image file and size as well as the assigned storage
189	pool. At the end of each line there is a \ucsMenuEntry{Delete}	190	pool. At the end of each line there is a \ucsMenuEntry{Delete}
190	button, which can be used to remove the drive (the image file can	191	button, which can be used to remove the drive (the image file can
Lines 195-225 Link Here
195	images can also be created for hard drives. These are created as	196	images can also be created for hard drives. These are created as
196	sparse files with the specified size, i.e., these files only grow when	197	sparse files with the specified size, i.e., these files only grow when
197	they are used and then up to the maximally specified size and thus	198	they are used and then up to the maximally specified size and thus
198	initially require only minimal memory space.	199	initially require only minimal disk space.
199		200
200	The basic settings of a virtual instance can be found	201	The basic settings of a virtual instance can be found in the \ucsMenuEntry{Settings} section.
201	in \ucsMenuEntry{Settings}. This includes the following fields	202	This includes the following fields
202	which can only be changed if the virtual instance is turned off.	203	which can only be changed if the virtual instance is turned off and no snapshots are used.
203		204
204	\begin{description}	205	\begin{description}
205	\item[Name] defines the name of the virtual machine. This does not	206	\item[Name] defines the name of the virtual machine. This does not
206	have to be the same as the name of the host in the LDAP directory.	207	have to be the same as the name of the host in the LDAP directory.
		208	\item[Operating System] can contain a description of the virtual instance or of the operating system used.
207	\item[Architecture] specifies the architecture of the emulated	209	\item[Architecture] specifies the architecture of the emulated
208	hardware. It must be noted that virtual 64-bit machines can only be	210	hardware. It must be noted that virtual 64 bit machines can only be
209	created on virtualisation servers with an amd64 architecture. This is	211	created on virtualisation servers using the amd64 architecture.
210	also suppressed on i386 systems by the UMC module.	212	This setting is not shown on i386 systems.
211	\item[Number of CPUs] defines how many virtual CPUs are assigned to	213	\item[Number of CPUs] defines how many virtual CPUs are assigned to
212	the virtual instance.	214	the virtual instance.
213	\item[MAC address] specifies the hardware address of the network	215	\item[MAC address] specifies the hardware address of the network
214	interface. If this field is not completed, a random value is	216	interface. If this field is left empty, a random value is
215	automatically entered.	217	automatically generated.
216	\item[Memory] specifies the size of the system memory.	218	\item[Memory] specifies the size of the system memory.
217	\item[Interface] defines the interface used for the bridge on the	219	\item[Interface] defines the interface used for the bridge on the
218	physical server. This is usually \emph{eth0}, which is also the	220	physical server. This is usually \emph{eth0}, which is also the
219	default setting.	221	default setting.
220	\end{description}	222	\end{description}
221		223
222	In the third area \emph{Extended settings}, you can find the following	224	In the last section \emph{Extended settings}, you can find the following
223	attributes:	225	attributes:
224		226
225	\begin{description}	227	\begin{description}
Lines 230-242 Link Here
230	the virtual machine searches the drives for bootable media. This	232	the virtual machine searches the drives for bootable media. This
231	setting is only available for fully-virtualised instances. For	233	setting is only available for fully-virtualised instances. For
232	paravirtualised instances it is defined by the order of the drives.	234	paravirtualised instances it is defined by the order of the drives.
233	\item[VNC remote access] defines whether VNC access to the virtual	235	\item[Direct access] defines whether VNC access to the virtual
234	machine is available. If the option is activated, the UMC module	236	machine is available. If the option is activated, the UMC module
235	can be used to start a VNC program directly. The VNC URL is displayed in a tool tip.	237	can be used to start a VNC program directly. The VNC URL is displayed in a tool tip.
236	A Java VNC program is used for this in the default setting. \ucsUCRV{uvmm/umc/vnc} can be	238	A Java VNC program is used for this in the default setting.
237	used to define the \emph{external} value, which means that an external	239	By switching the \ucsUCRV{uvmm/umc/vnc} to the value of \emph{external}, an external
238	program should be used. This must be installed on the workplace	240	program can be used instead.
239	computer and linked with the URI scheme vnc://.	241	This requires the web browser on the workstation computer to be configured properly to handle the URI scheme \ucsURL{vnc://}.
240	\item[Available globally] defines whether the VNC remote access is	242	\item[Available globally] defines whether the VNC remote access is
241	also possible from remote systems. If the option is not activated, the	243	also possible from remote systems. If the option is not activated, the
242	VNC session can only be accessed from the virtualisation server.	244	VNC session can only be accessed from the virtualisation server.
Lines 248-269 Link Here
248	\subsection{Removing virtual machines}	250	\subsection{Removing virtual machines}
249	Virtual instances no longer required can be deleted along with all	251	Virtual instances no longer required can be deleted along with all
250	their hard drives and ISO images. The images to be deleted can be	252	their hard drives and ISO images. The images to be deleted can be
251	selected in a list. It must be noted that ISO images and sometimes	253	selected from a list. It must be noted that ISO images and sometimes
252	also hard drive images may still be being used by other instances.	254	also hard drive images may be used by multiple instances.
		255	They only should be deleted when the are no longer used by any instance.
253		256
254	\subsection{Starting/stopping/suspending virtual machines}	257	\subsection{Starting/stopping/suspending virtual machines}
255	Instances created via UVMM are turned off in the initial status. This	258	Instances created via UVMM are turned off in the initial status. This
256	status can changed in the overview of the respective virtualisation server	259	status can changed in the overview of the respective virtualisation server
257	in the respective list entry or in the overview of the virtual	260	in the respective list entry or in the overview of the virtual
258	machine itself. In the latter case, there is	261	machine itself. In the latter case, there is
259	an \ucsMenuEntry{Operations} option, in which the status can be	262	an \ucsMenuEntry{Operations} section, in which the status can be
260	set. The following possibilities exist:	263	set. The following possibilities exist:
261		264
262	\begin{description}	265	\begin{description}
263	\item[Start] starts the virtual machine.	266	\item[Start] starts the virtual machine.
264	\item[Stop] turns the virtual machine off. It must be noted that	267	\item[Stop] turns the virtual machine off. It must be noted that
265	the operating system is not turned off first, i.e., it should be	268	the operating system is not turned off first, i.e., it should be
266	compared with the turning off of a computer.	269	compared with turning off a computer by pulling the power plug.
267	\item[Pause] assigns the instance no further CPU time. This still	270	\item[Pause] assigns the instance no further CPU time. This still
268	uses the working memory on the physical host, but the instance itself	271	uses the working memory on the physical host, but the instance itself
269	is paused.	272	is paused.
Lines 278-316 Link Here
278	\end{description}	281	\end{description}
279		282
280	\subsection{Migrating virtual machines}	283	\subsection{Migrating virtual machines}
281	A further function which can be found in the \emph{Operations} area	284	A further function which can be found in the \emph{Operations} section
282	of the overview is the possibility of a migrating a virtual machine	285	of the overview is the possibility of a migrating a virtual machine
283	to another virtualisation server. This works with both paused and running	286	to another virtualisation server. This works with both paused and running
284	instances (live migration).	287	instances (live migration).
285		288
286	During the migration it must be noted that the images of the mounted	289	For migration to work it must be noted that the images of the mounted
287	hard drives and CDROM drive must be in the same directory on both	290	hard drives and CDROM drive must be available in the same location on both
288	physical servers. This can be done, for example, by storing the images	291	physical servers. This can be archived, for example, by storing the images
289	in a central storage system.	292	in a central storage system.
290		293
291	\subsection{Managing snapshots}	294	\subsection{Managing snapshots}
292		295
293	UVMM offers the possibility to save the contents of the main and	296	UVMM offers the possibility to save the contents of the main and
294	hard drive memory of a virtual machine in the \ucsName{Snapshots}	297	hard drive memory of a virtual machine in \ucsName{Snapshots}.
295	menu. This allows the administator to revert to these snapshots	298	This allows the administrator to revert the virtual instance back to these snapshots
296	at a later point in time, which makes them a useful ``safety net''	299	at a later point in time, which makes them useful as a ``safety net''
297	when installing software updates.	300	when installing software updates.
298		301
299	Snapshots can only be used in KVM instances which access their hard	302	Snapshots can only be used with KVM instances which access all their hard
300	drive images in Qcow2 format. All snapshots are stored using	303	drive images in Qcow2 format. All snapshots are stored using
301	copy-on-write (see \ref{uvmm:instanz:erstellen}) directly in	304	copy-on-write (see \ref{uvmm:instanz:erstellen}) directly in
302	the hard drive image file.	305	the hard drive image file.
303		306
304	The administration is performed via \ucsMenuEntry{Snapshots} in the	307	The administration is performed in the \ucsMenuEntry{Snapshots} section in the
305	settings of a virtual machine.	308	settings of a virtual machine.
306		309
307	\ucsMenuEntry{Create new snapshot} can be used to create a	310	\ucsMenuEntry{Create new snapshot} can be used to create a
308	snapshot with the name of your choice, e.g., \emph{DC Master before	311	snapshot with the name of your choice, e.g., \emph{DC Master before
309	update to UCS 2.4-2}. This is then listed with its time of	312	update to UCS 2.4-2}.
310	creation. \ucsMenuEntry{Revert} can be used to return the machine to	313	In addition to the description the time is saved when the snapshot is created.
		314	The following list shows all available snapshots ordered reverse-chronologically.
		315	\ucsMenuEntry{Revert} can be used to return the machine to
311	an earlier snapshot and \ucsMenuEntry{Delete} can be used to	316	an earlier snapshot and \ucsMenuEntry{Delete} can be used to
312	remove a snapshot.	317	remove a snapshot.
313
314
315
316

Lines 66-77 Link Here

(-)doku/uvmm/uvmm.tex (-8 / +9 lines)
66	unterschiedliche Vor- und Nachteile. KVM beispielsweise benötigt	66	unterschiedliche Vor- und Nachteile. KVM beispielsweise benötigt
67	zwingend CPU-Virtualisierungunterstützung während Xen auch (eingeschränkt)	67	zwingend CPU-Virtualisierungunterstützung während Xen auch (eingeschränkt)
68	Systeme ohne Unterstützung durch die Hardware virtualisieren kann. Zu	68	Systeme ohne Unterstützung durch die Hardware virtualisieren kann. Zu
69	Details können die Webseiten der beiden Projekte konsultiert werden	69	Details können die Webseiten der beiden Projekte konsultiert werden:
70	(\ucsURL{http://www.linux-kvm.org/} und \ucsURL{http://www.xen.org/}).	70	\ucsURL{http://www.linux-kvm.org/} und \ucsURL{http://www.xen.org/}.
71		71
72	Zusätzlich sollte bei der Installation der Virtualisierungsserver die	72	Zusätzlich sollte bei der Installation der Virtualisierungsserver die
73	Architektur beachtet werden. Nur auf UCS-Systemen, die mit der	73	Architektur beachtet werden. Nur auf UCS-Systemen, die mit der
74	amd64-Architektur installiert sind, können auch 64Bit-Systeme	74	amd64-Architektur installiert sind, können auch 64 Bit-Systeme
75	virtualisiert werden.	75	virtualisiert werden.
76		76
77	\section{UMC-Modul}	77	\section{UMC-Modul}
Lines 171-178 Link Here
171	Verzeichnis} zur Verfügung. Dieser liegt auf den Virtualisierungs-Servern unterhalb	171	Verzeichnis} zur Verfügung. Dieser liegt auf den Virtualisierungs-Servern unterhalb
172	des Verzeichnisses \ucsURL{/var/lib/libvirt/images/} (weitere	172	des Verzeichnisses \ucsURL{/var/lib/libvirt/images/} (weitere
173	Informationen zur Verwaltung von Speicherbereichen sind im \href{http://wiki.univention.de/index.php?title=UVMM_Quickstart}{Wiki} zu	173	Informationen zur Verwaltung von Speicherbereichen sind im \href{http://wiki.univention.de/index.php?title=UVMM_Quickstart}{Wiki} zu
174	finden). Zur Einbindung von ISO-Images für CDROM-Laufwerke können	174	finden).
175	diese ebenfalls in das Verzeichnis kopiert werden. Anschließend stehen sie sofort zur	175	Zum Einbinden als CDROM-Laufwerke können ISO-Images ebenfalls in diese Verzeichnis kopiert werden.
		176	Anschließend stehen sie sofort zur
176	Verfügung und können mit neuen Laufwerken verknüpft werden.	177	Verfügung und können mit neuen Laufwerken verknüpft werden.
177		178
178	Werden Laufwerke für eine neu zu installierende Instanz definiert,	179	Werden Laufwerke für eine neu zu installierende Instanz definiert,
Lines 186-192 Link Here
186		187
187	Ist eine virtuelle Instanz mit dem Assistenten erfolgreich angelegt	188	Ist eine virtuelle Instanz mit dem Assistenten erfolgreich angelegt
188	worden, zeigt das UMC-Modul sofort die Übersicht zu der neuen Instanz	189	worden, zeigt das UMC-Modul sofort die Übersicht zu der neuen Instanz
189	an. Die Einstellungen einer Instanz sind in drei Bereiche aufgeteilt	190	an. Die Einstellungen einer Instanz sind in mehrere Bereiche aufgeteilt
190	(Abbildung \ref{pic:uvmm-domain-settings}):	191	(Abbildung \ref{pic:uvmm-domain-settings}):
191		192
192	\begin{itemize}	193	\begin{itemize}
Lines 213-219 Link Here
213		214
214	Die Grundeinstellungen einer virtuellen Instanz sind unter \ucsMenuEntry{Einstellungen}	215	Die Grundeinstellungen einer virtuellen Instanz sind unter \ucsMenuEntry{Einstellungen}
215	zu finden. Dort gibt es folgende Felder, die nur verändert	216	zu finden. Dort gibt es folgende Felder, die nur verändert
216	werden können, wenn die virtuelle Instanz ausgeschaltet ist:	217	werden können, wenn die virtuelle Instanz ausgeschaltet ist und keine Sicherungspunkte angelegt sind:
217		218
218	\begin{description}	219	\begin{description}
219	\item[Name] definiert den Namen der virtuellen Instanz. Dieser muss	220	\item[Name] definiert den Namen der virtuellen Instanz. Dieser muss
Lines 222-228 Link Here
222	installierten Betriebssystems genutzt werden	223	installierten Betriebssystems genutzt werden
223	\item[Architektur] legt die Architektur der emulierten Hardware	224	\item[Architektur] legt die Architektur der emulierten Hardware
224	fest. Dabei ist zu beachten, dass nur auf Virtualisierungs-Servern	225	fest. Dabei ist zu beachten, dass nur auf Virtualisierungs-Servern
225	der Architektur amd64 virtuelle 64-Bit-Instanzen angelegt werden	226	der Architektur amd64 virtuelle 64 Bit-Instanzen angelegt werden
226	können. Dies wird vom UMC-Modul auf i386-Systemen auch unterbunden.	227	können. Dies wird vom UMC-Modul auf i386-Systemen auch unterbunden.
227	\item[Anzahl der CPUs] definiert wieviele virtuelle CPUs der virtuellen	228	\item[Anzahl der CPUs] definiert wieviele virtuelle CPUs der virtuellen
228	Instanz zugeteilt werden.	229	Instanz zugeteilt werden.