OpenVZ Virtuozzo Containers Wiki - User contributions [en]

Migration from Linux-VServer to OpenVZ

2009-12-21T23:58:20Z

Jasond: /* Ubuntu udev */ formatting chages

{{Roughstub}}

This article describes the migration from Linux-VServer to OpenVZ.

== Details of migration process ==

=== Initial conditions ===

The following example of Linux-VServer based solution was used for the experiment:

* Kernel linux-2.6.17.13 was patched by the patch-2.6.17.13-vs2.0.2.1.diff and rebuild;
* Util-vserver-0.30.211 tools were used for creating containers;

# vserver-info
Versions:
Kernel: 2.6.17.13-vs2.0.2.1
VS-API: 0x00020002
util-vserver: 0.30.211; Dec 5 2006, 17:10:21

Features:
CC: gcc, gcc (GCC) 3.4.3 20041212 (Red Hat 3.4.3-9.EL4)
CXX: g++, g++ (GCC) 3.4.3 20041212 (Red Hat 3.4.3-9.EL4)
CPPFLAGS: ''
CFLAGS: '-g -O2 -std=c99 -Wall -pedantic -W -funit-at-a-time'
CXXFLAGS: '-g -O2 -ansi -Wall -pedantic -W -fmessage-length=0 -funit-at-a-time'
build/host: i686-pc-linux-gnu/i686-pc-linux-gnu
Use dietlibc: yes
Build C++ programs: yes
Build C99 programs: yes
Available APIs: v13,net
ext2fs Source: kernel
syscall(2) invocation: alternative
vserver(2) syscall#: 273/glibc

Paths:
prefix: /usr/local
sysconf-Directory: ${prefix}/etc
cfg-Directory: ${prefix}/etc/vservers
initrd-Directory: $(sysconfdir)/init.d
pkgstate-Directory: ${prefix}/var/run/vservers
vserver-Rootdir: /vservers
#

VServer v345 was built using vserver vX build utility and populated by using the tarballed template of Fedora Core 4.

# vserver v345 start
Starting system logger: [ OK ]
Initializing random number generator: [ OK ]
Starting crond: l: [ OK ]
Starting atd: [ OK ]
# vserver v345 enter
[/]# ls -l
total 44
drwxr-xr-x 2 root root 4096 Oct 26 2004 bin
drwxr-xr-x 3 root root 4096 Dec 8 17:16 dev
drwxr-xr-x 27 root root 4096 Dec 8 15:21 etc
-rw-r--r-- 1 root root 0 Dec 8 15:33 halt
drwxr-xr-x 2 root root 4096 Jan 24 2003 home
drwxr-xr-x 7 root root 4096 Oct 26 2004 lib
drwxr-xr-x 2 root root 4096 Jan 24 2003 mnt
drwxr-xr-x 3 root root 4096 Oct 26 2004 opt
-rw-r--r-- 1 root root 0 Dec 7 20:17 poweroff
dr-xr-xr-x 80 root root 0 Dec 8 11:38 proc
drwxr-x--- 2 root root 4096 Dec 7 20:17 root
drwxr-xr-x 2 root root 4096 Oct 26 2004 sbin
drwxrwxrwt 2 root root 40 Dec 8 17:16 tmp
drwxr-xr-x 15 root root 4096 Jul 27 2004 usr
drwxr-xr-x 17 root root 4096 Oct 26 2004 var
[/]# sh
sh-2.05b#
.........

As a result we obtain running virtual environment v345:

# vserver-stat

CTX PROC VSZ RSS userTIME sysTIME UPTIME NAME
0 51 90.9M 26.3M 0m58s75 2m42s57 33m45s93 root server
49153 4 10.2M 2.8M 0m00s00 0m00s11 21m45s42 v345

#

=== Starting migration to OpenVZ ===

Downloading and installing the stable OpenVZ kernel.

Install the OpenVZ kernel, as described in [[Quick installation]].

After the kernel is installed, reboot the machine. After rebooting and logging in you will see the following reply on vserver-stat call:

# vserver-stat
can not change context: migrate kernel feature missing and 'compat' API disabled: Function not implemented

It is a natural thing that now virtual environment v345 is unavailable. The following steps will be devoted to making it
work over OpenVZ kernel.

=== Downloading and installing vzctl package ===

OpenVZ solution requires installing a set of tools: vzctl and vzquota packages. Download and install it, as described in [[quick installation]].

If rpm complains about unresolved dependencies, you'll have to satisfy them first, then repeat the installation.
Then launch the OpenVZ:

# /sbin/service vz start
Starting OpenVZ: [ OK ]
Bringing up interface venet0: [ OK ]
Configuring interface venet0: [ OK ]

Currently vzlist utility is unable to find any containers:
# vzlist
Containers not found

=== Updating different configurations ===

Move the existing guest OSs to the right place:

# cd /vz
# mkdir private
# mkdir private/345
# mv /vservers/v345 /vz/private/345

Now it is time for creating configuration files for OpenVZ container. Use the basic sample
configuration presented in /etc/sysconfig/vz-scripts/ve-vps.basic.conf-sample file:

# cd /etc/sysconfig/vz-scripts
# cp ve-vps.basic.conf-sample 345.conf

Now, let's set some parameters for the new container.

First, we need to tell which distro the container is running:
# echo "OSTEMPLATE="fedora-core-4" >> 345.conf

Then we set a few more parameters:
vzctl set 345 --onboot yes --save # to make it start upon reboot
vzctl set 345 --ipadd 192.168.0.145 --save
vzctl set 345 --hostname test345.my.org --save

== Testing how the guest OSs successfully work over OpenVZ ==

Now you can start a container:

# vzctl start 345

and see if it's running:
# vzlist -a
CTID NPROC STATUS IP_ADDR HOSTNAME
345 5 running 192.168.0.145 test345.my.org

You can run commands in it:

# vzctl exec 345 ls -l
total 48
drwxr-xr-x 2 root root 4096 Oct 26 2004 bin
drwxr-xr-x 3 root root 4096 Dec 11 12:42 dev
drwxr-xr-x 27 root root 4096 Dec 11 12:44 etc
-rw-r--r-- 1 root root 0 Dec 11 12:13 fastboot
-rw-r--r-- 1 root root 0 Dec 8 15:33 halt
drwxr-xr-x 2 root root 4096 Jan 24 2003 home
drwxr-xr-x 7 root root 4096 Oct 26 2004 lib
drwxr-xr-x 2 root root 4096 Jan 24 2003 mnt
drwxr-xr-x 3 root root 4096 Oct 26 2004 opt
-rw-r--r-- 1 root root 0 Dec 7 20:17 poweroff
dr-xr-xr-x 70 root root 0 Dec 11 12:42 proc
drwxr-x--- 2 root root 4096 Dec 7 20:17 root
drwxr-xr-x 2 root root 4096 Dec 11 12:13 sbin
drwxrwxrwt 2 root root 4096 Dec 8 12:40 tmp
drwxr-xr-x 15 root root 4096 Jul 27 2004 usr
drwxr-xr-x 17 root root 4096 Oct 26 2004 var

== Issues ==

=== Networking ===

==== Starting networking in VEs ====

The vserver-originating containers do not initialize network at all. Thus one needs to use following command to enable networking start (inside of the migrated container):
cd /etc/rcS.d
ln -s ../init.d/networking S40networking

==== Migrating your VServer Shorewall setup ====

If you had the [http://www.shorewall.net/ Shorewall firewall] running on the hardware node to route traffic to and from your guests, here are a couple of advices, provided you want a networking setup close to what you had with Vserver (i.e. running <code>vnet</code> interfaces, not <code>veth</code> ones) :
* do not use the <code>venet0</code> interface in Shorewall's configuration as the <code>vz</code> service starts after Shorewall (at least on Debian) and thus the interface does not exist when Shorewall starts. Do not use <code>detect</code> for the broadcast in <code>/etc/shorewall/interfaces</code>.
* for your VEs to be able to talk to each other, use the <code>routeback</code> option for <code>venet0</code> (and others) in <code>/etc/shorewall/interfaces</code>.

==== IP src from VEs ====

If you run a mail server in a VE, and if the hardware node has multiple network interfaces, you may have mail routing issues because of the originated IP address of the packets coming from the hardware node. Simply specify an interface in <code>/etc/vz/vz.conf</code> :
<pre>VE_ROUTE_SRC_DEV="iface_name"</pre>

=== Disk space information ===

Disk space information is empty. Do the following to fix:
rm /etc/mtab
ln -s /proc/mounts /etc/mtab

=== /dev ===

Vserver mounts /dev/pts filesystem for container transparently, whereas openvz does not. To compensate the ommission, you need to move aside /dev directory in the vserver-originating container and copy /dev directory from openvz based container.

=== Ubuntu udev ===

Additionally, Ubuntu based vservers have the udev package installed which prevents access to the console in openvz. This error message is an example of the problem:

# vzctl enter 345
enter into CT 345 failed
Unable to open pty: No such file or directory

The fix is to remove the udev package from the guest:

# vzctl exec 345 'dpkg --force-depends --purge udev'
(Reading database ... dpkg: udev: dependency problems, but removing anyway as you request:
initramfs-tools depends on udev (>= 117-5).
15227 files and directories currently installed.)
Removing udev ...
Purging configuration files for udev ...
dpkg - warning: while removing udev, directory `/lib/udev/devices/net' not empty so not removed.
dpkg - warning: while removing udev, directory `/lib/udev/devices' not empty so not removed.

Now restart the container, you should now be able to use the console.

# vzctl restart 345
Restarting container
...
<SNIP>
...
Container start in progress...

# vzctl enter 345
entered into CT 345
root@test:/#

=== /proc ===

The /proc filesystem is not automatically mounted by openvz. So the vserver needs to mount it itself. The simplests (not the best) way it can be done, is by sticking following command at the end of /etc/init.d/bootmisc.sh:
mount /proc

[[Category:HOWTO]]

Migration from Linux-VServer to OpenVZ

2009-12-21T23:52:53Z

Jasond: /* /dev */

{{Roughstub}}

This article describes the migration from Linux-VServer to OpenVZ.

== Details of migration process ==

=== Initial conditions ===

The following example of Linux-VServer based solution was used for the experiment:

* Kernel linux-2.6.17.13 was patched by the patch-2.6.17.13-vs2.0.2.1.diff and rebuild;
* Util-vserver-0.30.211 tools were used for creating containers;

# vserver-info
Versions:
Kernel: 2.6.17.13-vs2.0.2.1
VS-API: 0x00020002
util-vserver: 0.30.211; Dec 5 2006, 17:10:21

Features:
CC: gcc, gcc (GCC) 3.4.3 20041212 (Red Hat 3.4.3-9.EL4)
CXX: g++, g++ (GCC) 3.4.3 20041212 (Red Hat 3.4.3-9.EL4)
CPPFLAGS: ''
CFLAGS: '-g -O2 -std=c99 -Wall -pedantic -W -funit-at-a-time'
CXXFLAGS: '-g -O2 -ansi -Wall -pedantic -W -fmessage-length=0 -funit-at-a-time'
build/host: i686-pc-linux-gnu/i686-pc-linux-gnu
Use dietlibc: yes
Build C++ programs: yes
Build C99 programs: yes
Available APIs: v13,net
ext2fs Source: kernel
syscall(2) invocation: alternative
vserver(2) syscall#: 273/glibc

Paths:
prefix: /usr/local
sysconf-Directory: ${prefix}/etc
cfg-Directory: ${prefix}/etc/vservers
initrd-Directory: $(sysconfdir)/init.d
pkgstate-Directory: ${prefix}/var/run/vservers
vserver-Rootdir: /vservers
#

VServer v345 was built using vserver vX build utility and populated by using the tarballed template of Fedora Core 4.

# vserver v345 start
Starting system logger: [ OK ]
Initializing random number generator: [ OK ]
Starting crond: l: [ OK ]
Starting atd: [ OK ]
# vserver v345 enter
[/]# ls -l
total 44
drwxr-xr-x 2 root root 4096 Oct 26 2004 bin
drwxr-xr-x 3 root root 4096 Dec 8 17:16 dev
drwxr-xr-x 27 root root 4096 Dec 8 15:21 etc
-rw-r--r-- 1 root root 0 Dec 8 15:33 halt
drwxr-xr-x 2 root root 4096 Jan 24 2003 home
drwxr-xr-x 7 root root 4096 Oct 26 2004 lib
drwxr-xr-x 2 root root 4096 Jan 24 2003 mnt
drwxr-xr-x 3 root root 4096 Oct 26 2004 opt
-rw-r--r-- 1 root root 0 Dec 7 20:17 poweroff
dr-xr-xr-x 80 root root 0 Dec 8 11:38 proc
drwxr-x--- 2 root root 4096 Dec 7 20:17 root
drwxr-xr-x 2 root root 4096 Oct 26 2004 sbin
drwxrwxrwt 2 root root 40 Dec 8 17:16 tmp
drwxr-xr-x 15 root root 4096 Jul 27 2004 usr
drwxr-xr-x 17 root root 4096 Oct 26 2004 var
[/]# sh
sh-2.05b#
.........

As a result we obtain running virtual environment v345:

# vserver-stat

CTX PROC VSZ RSS userTIME sysTIME UPTIME NAME
0 51 90.9M 26.3M 0m58s75 2m42s57 33m45s93 root server
49153 4 10.2M 2.8M 0m00s00 0m00s11 21m45s42 v345

#

=== Starting migration to OpenVZ ===

Downloading and installing the stable OpenVZ kernel.

Install the OpenVZ kernel, as described in [[Quick installation]].

After the kernel is installed, reboot the machine. After rebooting and logging in you will see the following reply on vserver-stat call:

# vserver-stat
can not change context: migrate kernel feature missing and 'compat' API disabled: Function not implemented

It is a natural thing that now virtual environment v345 is unavailable. The following steps will be devoted to making it
work over OpenVZ kernel.

=== Downloading and installing vzctl package ===

OpenVZ solution requires installing a set of tools: vzctl and vzquota packages. Download and install it, as described in [[quick installation]].

If rpm complains about unresolved dependencies, you'll have to satisfy them first, then repeat the installation.
Then launch the OpenVZ:

# /sbin/service vz start
Starting OpenVZ: [ OK ]
Bringing up interface venet0: [ OK ]
Configuring interface venet0: [ OK ]

Currently vzlist utility is unable to find any containers:
# vzlist
Containers not found

=== Updating different configurations ===

Move the existing guest OSs to the right place:

# cd /vz
# mkdir private
# mkdir private/345
# mv /vservers/v345 /vz/private/345

Now it is time for creating configuration files for OpenVZ container. Use the basic sample
configuration presented in /etc/sysconfig/vz-scripts/ve-vps.basic.conf-sample file:

# cd /etc/sysconfig/vz-scripts
# cp ve-vps.basic.conf-sample 345.conf

Now, let's set some parameters for the new container.

First, we need to tell which distro the container is running:
# echo "OSTEMPLATE="fedora-core-4" >> 345.conf

Then we set a few more parameters:
vzctl set 345 --onboot yes --save # to make it start upon reboot
vzctl set 345 --ipadd 192.168.0.145 --save
vzctl set 345 --hostname test345.my.org --save

== Testing how the guest OSs successfully work over OpenVZ ==

Now you can start a container:

# vzctl start 345

and see if it's running:
# vzlist -a
CTID NPROC STATUS IP_ADDR HOSTNAME
345 5 running 192.168.0.145 test345.my.org

You can run commands in it:

# vzctl exec 345 ls -l
total 48
drwxr-xr-x 2 root root 4096 Oct 26 2004 bin
drwxr-xr-x 3 root root 4096 Dec 11 12:42 dev
drwxr-xr-x 27 root root 4096 Dec 11 12:44 etc
-rw-r--r-- 1 root root 0 Dec 11 12:13 fastboot
-rw-r--r-- 1 root root 0 Dec 8 15:33 halt
drwxr-xr-x 2 root root 4096 Jan 24 2003 home
drwxr-xr-x 7 root root 4096 Oct 26 2004 lib
drwxr-xr-x 2 root root 4096 Jan 24 2003 mnt
drwxr-xr-x 3 root root 4096 Oct 26 2004 opt
-rw-r--r-- 1 root root 0 Dec 7 20:17 poweroff
dr-xr-xr-x 70 root root 0 Dec 11 12:42 proc
drwxr-x--- 2 root root 4096 Dec 7 20:17 root
drwxr-xr-x 2 root root 4096 Dec 11 12:13 sbin
drwxrwxrwt 2 root root 4096 Dec 8 12:40 tmp
drwxr-xr-x 15 root root 4096 Jul 27 2004 usr
drwxr-xr-x 17 root root 4096 Oct 26 2004 var

== Issues ==

=== Networking ===

==== Starting networking in VEs ====

The vserver-originating containers do not initialize network at all. Thus one needs to use following command to enable networking start (inside of the migrated container):
cd /etc/rcS.d
ln -s ../init.d/networking S40networking

==== Migrating your VServer Shorewall setup ====

If you had the [http://www.shorewall.net/ Shorewall firewall] running on the hardware node to route traffic to and from your guests, here are a couple of advices, provided you want a networking setup close to what you had with Vserver (i.e. running <code>vnet</code> interfaces, not <code>veth</code> ones) :
* do not use the <code>venet0</code> interface in Shorewall's configuration as the <code>vz</code> service starts after Shorewall (at least on Debian) and thus the interface does not exist when Shorewall starts. Do not use <code>detect</code> for the broadcast in <code>/etc/shorewall/interfaces</code>.
* for your VEs to be able to talk to each other, use the <code>routeback</code> option for <code>venet0</code> (and others) in <code>/etc/shorewall/interfaces</code>.

==== IP src from VEs ====

If you run a mail server in a VE, and if the hardware node has multiple network interfaces, you may have mail routing issues because of the originated IP address of the packets coming from the hardware node. Simply specify an interface in <code>/etc/vz/vz.conf</code> :
<pre>VE_ROUTE_SRC_DEV="iface_name"</pre>

=== Disk space information ===

Disk space information is empty. Do the following to fix:
rm /etc/mtab
ln -s /proc/mounts /etc/mtab

=== /dev ===

Vserver mounts /dev/pts filesystem for container transparently, whereas openvz does not. To compensate the ommission, you need to move aside /dev directory in the vserver-originating container and copy /dev directory from openvz based container.

=== Ubuntu udev ===

Additionally, Ubuntu based vservers have the udev package installed which prevents access to the console in openvz. This error message is an example of the problem:

<code>
# vzctl enter 101
enter into CT 101 failed
Unable to open pty: No such file or directory
</code>

The fix is to remove the udev package from the guest:

<code>
# vzctl exec 101 'dpkg --force-depends --purge udev'
(Reading database ... dpkg: udev: dependency problems, but removing anyway as you request:
initramfs-tools depends on udev (>= 117-5).
15227 files and directories currently installed.)
Removing udev ...
Purging configuration files for udev ...
dpkg - warning: while removing udev, directory `/lib/udev/devices/net' not empty so not removed.
dpkg - warning: while removing udev, directory `/lib/udev/devices' not empty so not removed.
</code>

Now restart the container, you should now be able to use the console.

<code>
# vzctl restart 101
Restarting container
...
<SNIP>
...
Container start in progress...

# vzctl enter 101
entered into CT 101
root@test:/#
</code>

=== /proc ===

The /proc filesystem is not automatically mounted by openvz. So the vserver needs to mount it itself. The simplests (not the best) way it can be done, is by sticking following command at the end of /etc/init.d/bootmisc.sh:
mount /proc

[[Category:HOWTO]]

Migration from Linux-VServer to OpenVZ

2009-12-21T23:51:23Z

Jasond: Added note to remove udev from ubuntu guest

{{Roughstub}}

This article describes the migration from Linux-VServer to OpenVZ.

== Details of migration process ==

=== Initial conditions ===

The following example of Linux-VServer based solution was used for the experiment:

* Kernel linux-2.6.17.13 was patched by the patch-2.6.17.13-vs2.0.2.1.diff and rebuild;
* Util-vserver-0.30.211 tools were used for creating containers;

# vserver-info
Versions:
Kernel: 2.6.17.13-vs2.0.2.1
VS-API: 0x00020002
util-vserver: 0.30.211; Dec 5 2006, 17:10:21

Features:
CC: gcc, gcc (GCC) 3.4.3 20041212 (Red Hat 3.4.3-9.EL4)
CXX: g++, g++ (GCC) 3.4.3 20041212 (Red Hat 3.4.3-9.EL4)
CPPFLAGS: ''
CFLAGS: '-g -O2 -std=c99 -Wall -pedantic -W -funit-at-a-time'
CXXFLAGS: '-g -O2 -ansi -Wall -pedantic -W -fmessage-length=0 -funit-at-a-time'
build/host: i686-pc-linux-gnu/i686-pc-linux-gnu
Use dietlibc: yes
Build C++ programs: yes
Build C99 programs: yes
Available APIs: v13,net
ext2fs Source: kernel
syscall(2) invocation: alternative
vserver(2) syscall#: 273/glibc

Paths:
prefix: /usr/local
sysconf-Directory: ${prefix}/etc
cfg-Directory: ${prefix}/etc/vservers
initrd-Directory: $(sysconfdir)/init.d
pkgstate-Directory: ${prefix}/var/run/vservers
vserver-Rootdir: /vservers
#

VServer v345 was built using vserver vX build utility and populated by using the tarballed template of Fedora Core 4.

# vserver v345 start
Starting system logger: [ OK ]
Initializing random number generator: [ OK ]
Starting crond: l: [ OK ]
Starting atd: [ OK ]
# vserver v345 enter
[/]# ls -l
total 44
drwxr-xr-x 2 root root 4096 Oct 26 2004 bin
drwxr-xr-x 3 root root 4096 Dec 8 17:16 dev
drwxr-xr-x 27 root root 4096 Dec 8 15:21 etc
-rw-r--r-- 1 root root 0 Dec 8 15:33 halt
drwxr-xr-x 2 root root 4096 Jan 24 2003 home
drwxr-xr-x 7 root root 4096 Oct 26 2004 lib
drwxr-xr-x 2 root root 4096 Jan 24 2003 mnt
drwxr-xr-x 3 root root 4096 Oct 26 2004 opt
-rw-r--r-- 1 root root 0 Dec 7 20:17 poweroff
dr-xr-xr-x 80 root root 0 Dec 8 11:38 proc
drwxr-x--- 2 root root 4096 Dec 7 20:17 root
drwxr-xr-x 2 root root 4096 Oct 26 2004 sbin
drwxrwxrwt 2 root root 40 Dec 8 17:16 tmp
drwxr-xr-x 15 root root 4096 Jul 27 2004 usr
drwxr-xr-x 17 root root 4096 Oct 26 2004 var
[/]# sh
sh-2.05b#
.........

As a result we obtain running virtual environment v345:

# vserver-stat

CTX PROC VSZ RSS userTIME sysTIME UPTIME NAME
0 51 90.9M 26.3M 0m58s75 2m42s57 33m45s93 root server
49153 4 10.2M 2.8M 0m00s00 0m00s11 21m45s42 v345

#

=== Starting migration to OpenVZ ===

Downloading and installing the stable OpenVZ kernel.

Install the OpenVZ kernel, as described in [[Quick installation]].

After the kernel is installed, reboot the machine. After rebooting and logging in you will see the following reply on vserver-stat call:

# vserver-stat
can not change context: migrate kernel feature missing and 'compat' API disabled: Function not implemented

It is a natural thing that now virtual environment v345 is unavailable. The following steps will be devoted to making it
work over OpenVZ kernel.

=== Downloading and installing vzctl package ===

OpenVZ solution requires installing a set of tools: vzctl and vzquota packages. Download and install it, as described in [[quick installation]].

If rpm complains about unresolved dependencies, you'll have to satisfy them first, then repeat the installation.
Then launch the OpenVZ:

# /sbin/service vz start
Starting OpenVZ: [ OK ]
Bringing up interface venet0: [ OK ]
Configuring interface venet0: [ OK ]

Currently vzlist utility is unable to find any containers:
# vzlist
Containers not found

=== Updating different configurations ===

Move the existing guest OSs to the right place:

# cd /vz
# mkdir private
# mkdir private/345
# mv /vservers/v345 /vz/private/345

Now it is time for creating configuration files for OpenVZ container. Use the basic sample
configuration presented in /etc/sysconfig/vz-scripts/ve-vps.basic.conf-sample file:

# cd /etc/sysconfig/vz-scripts
# cp ve-vps.basic.conf-sample 345.conf

Now, let's set some parameters for the new container.

First, we need to tell which distro the container is running:
# echo "OSTEMPLATE="fedora-core-4" >> 345.conf

Then we set a few more parameters:
vzctl set 345 --onboot yes --save # to make it start upon reboot
vzctl set 345 --ipadd 192.168.0.145 --save
vzctl set 345 --hostname test345.my.org --save

== Testing how the guest OSs successfully work over OpenVZ ==

Now you can start a container:

# vzctl start 345

and see if it's running:
# vzlist -a
CTID NPROC STATUS IP_ADDR HOSTNAME
345 5 running 192.168.0.145 test345.my.org

You can run commands in it:

# vzctl exec 345 ls -l
total 48
drwxr-xr-x 2 root root 4096 Oct 26 2004 bin
drwxr-xr-x 3 root root 4096 Dec 11 12:42 dev
drwxr-xr-x 27 root root 4096 Dec 11 12:44 etc
-rw-r--r-- 1 root root 0 Dec 11 12:13 fastboot
-rw-r--r-- 1 root root 0 Dec 8 15:33 halt
drwxr-xr-x 2 root root 4096 Jan 24 2003 home
drwxr-xr-x 7 root root 4096 Oct 26 2004 lib
drwxr-xr-x 2 root root 4096 Jan 24 2003 mnt
drwxr-xr-x 3 root root 4096 Oct 26 2004 opt
-rw-r--r-- 1 root root 0 Dec 7 20:17 poweroff
dr-xr-xr-x 70 root root 0 Dec 11 12:42 proc
drwxr-x--- 2 root root 4096 Dec 7 20:17 root
drwxr-xr-x 2 root root 4096 Dec 11 12:13 sbin
drwxrwxrwt 2 root root 4096 Dec 8 12:40 tmp
drwxr-xr-x 15 root root 4096 Jul 27 2004 usr
drwxr-xr-x 17 root root 4096 Oct 26 2004 var

== Issues ==

=== Networking ===

==== Starting networking in VEs ====

The vserver-originating containers do not initialize network at all. Thus one needs to use following command to enable networking start (inside of the migrated container):
cd /etc/rcS.d
ln -s ../init.d/networking S40networking

==== Migrating your VServer Shorewall setup ====

If you had the [http://www.shorewall.net/ Shorewall firewall] running on the hardware node to route traffic to and from your guests, here are a couple of advices, provided you want a networking setup close to what you had with Vserver (i.e. running <code>vnet</code> interfaces, not <code>veth</code> ones) :
* do not use the <code>venet0</code> interface in Shorewall's configuration as the <code>vz</code> service starts after Shorewall (at least on Debian) and thus the interface does not exist when Shorewall starts. Do not use <code>detect</code> for the broadcast in <code>/etc/shorewall/interfaces</code>.
* for your VEs to be able to talk to each other, use the <code>routeback</code> option for <code>venet0</code> (and others) in <code>/etc/shorewall/interfaces</code>.

==== IP src from VEs ====

If you run a mail server in a VE, and if the hardware node has multiple network interfaces, you may have mail routing issues because of the originated IP address of the packets coming from the hardware node. Simply specify an interface in <code>/etc/vz/vz.conf</code> :
<pre>VE_ROUTE_SRC_DEV="iface_name"</pre>

=== Disk space information ===

Disk space information is empty. Do the following to fix:
rm /etc/mtab
ln -s /proc/mounts /etc/mtab

=== /dev ===

Vserver mounts /dev/pts filesystem for container transparently, whereas openvz does not. To compensate the ommission, you need to move aside /dev directory in the vserver-originating container and copy /dev directory from openvz based container.

Additionally, Ubuntu based vservers have the udev package installed which prevents access to the console in openvz. This error message is an example of the problem:

<code>
# vzctl enter 101
enter into CT 101 failed
Unable to open pty: No such file or directory
</code>

The fix is to remove the udev package from the guest:

<code>
# vzctl exec 101 'dpkg --force-depends --purge udev'
(Reading database ... dpkg: udev: dependency problems, but removing anyway as you request:
initramfs-tools depends on udev (>= 117-5).
15227 files and directories currently installed.)
Removing udev ...
Purging configuration files for udev ...
dpkg - warning: while removing udev, directory `/lib/udev/devices/net' not empty so not removed.
dpkg - warning: while removing udev, directory `/lib/udev/devices' not empty so not removed.
</code>

Now restart the container, you should now be able to use the console.

<code>
# vzctl restart 101
Restarting container
...
<SNIP>
...
Container start in progress...

# vzctl enter 101
entered into CT 101
root@test:/#
</code>

=== /proc ===

The /proc filesystem is not automatically mounted by openvz. So the vserver needs to mount it itself. The simplests (not the best) way it can be done, is by sticking following command at the end of /etc/init.d/bootmisc.sh:
mount /proc

[[Category:HOWTO]]