Editing Virtuozzo Storage

= Parallels Cloud Storage (Pstorage) =

Parallels Storage (Pstorage) is a highly-available distributed storage (virtual SAN) with built-in replication and disaster recovery. Pstorage provides a storage virtualization platform on top of commodity hardware with locally attached hard drives and enables the unification of storage into a cluster in scenarios like virtualization with the help of virtual machines (VMs) and/or Containers (CTs). Pstorage ensures a fast live migration of VMs and CTs across hardware nodes, without the need to copy VM/CT data, and high availability as the storage becomes available remotely.

The main Pstorage features are listed below:

* No special hardware requirements. Commodity hardware (SATA/SAS drives, 1Gbit+ Ethernet) can be used to create a storage.
* Strong consistency semantics. This makes Pstorage suitable for iSCSI, VMs and CTs running on top of it (unlike object storage such as Amazon S3 or Swift).
* Built-in replication.
* Automatic disaster recovery on hard drive or node failures.
* High availability. Data remain accessible even in case of hard drive or node failures.
* Optional SSD caching. SSD caches boost the overall performance in the cluster on write and read operations.
* Data checksumming and scrubbing. Checksumming and scrubbing greatly enhance data reliability.
* Grow on demand. More storage nodes can be added to the cluster to increase its disk space. A VM/CT image size is not limited by the size of any of the hard drives.
* Scales to Petabytes
* More uniform hardware performance and capacity utilization across the nodes, so overutilized nodes benefit from idle ones.
* High performance - comparable to SAN.


See a brief [http://www.youtube.com/watch?v=6oEzW9w-1rg video on YouTube].

==OpenVZ limitations==
<span style="color:#FF0000">Parallels Cloud Storage is available as a TECHNOLOGY PREVIEW ONLY for OpenVZ users and can't be licensed for production.<br>To unlock for running in production you should upgrade to a full Parallels Cloud Server product (see below).<br>Maximum capacity limited for usage in technology preview mode is 100GB of logical (Containers usable) disk space.<br>After hitting this limit writers can get blocked w/o errors expecting for a limit to be extended, so please avoid hitting the limit (it's not a bug :) ).</span>

==Pstorage components==
Any Pstorage includes three components:

* Metadata server (MDS). MDSs manage metadata, like file names, and keep control over how files are split into chunks and where the chunks are stored. They also track versions of chunks and ensure that the cluster has enough replicas. An MDS can be run in multiple instances to provide high availability. Besides, MDSs keep a global log of important events that happen in the cluster.
* Chunk server (CS). A CS is a service responsible for storing real user data chunks and providing access to these data. A Pstorage cluster must have multiple instances of CSs for high availability.
* Clients. Clients access a Pstorage cluster by communicating with MDSs and CSs. Parallels Containers and virtual machines can be run natively, i.e. directly from the Pstorage cluster. An additional Pstorage client -  can be used to mount Pstorage as a conventional file system (though Pstorage is not POSIX-compliant). Besides, Pstorage files can be mounted as a block device using the "ploop" feature and formatted as ext4 file system for other needs.

A recommended cluster setup includes from 3 to 5 MDS instances (allowing you to survive the loss of 1 or 2 of MDSs, respectively) and multiple CSs providing storage capacity.


=Pstorage setup HOWTO=
Below HOWTO explains how to setup Parallels Cloud Storage (Pstorage) cluster and run OpenVZ containers stored there. Please note, that it's just a brief HOWTO for quick and easy evaluation of Parallels Cloud Storage (configuring only 1x MDS and CS service) and is not a real manual. We highly recommend to consult [http://download.parallels.com/doc/pcs/pdf/Parallels_Cloud_Storage.pdf Pstorage manual] and man pages (such as pstorage, pstorage-make-cs, pstorage-make-mds etc.) as it contain a lot of important details on types of SSD drives supported, what are the recommended configurations, how to configure big clusters with failure domains and so on.

==Installing Parallels Cloud Storage software==

In order to install Pstorage RPM packages log in as root to all the machines planned to be added to the cluster and perform the following actions.

Download and install the following RPM packages: pstorage-ctl, pstorage-libs-shared, pstorage-metadata-server, pstorage-chunk-server and pstorage-client. These packages can be downloaded from http://download.openvz.org/pstorage:

 wget http://download.openvz.org/pstorage/*
 yum install pstorage-ctl pstorage-libs-shared pstorage-metadata-server pstorage-chunk-server pstorage-client

==Creating a cluster==

Every Pstorage cluster has a unique cluster name used for remote service discovery and during authorization.
So choose a name for the cluster that will uniquely identify it among other clusters in your network and avoid reusing it on cluster recreate. A name may contain the characters a-z, A-Z, 0-9, dash (-), and underscore (_). Here we will use 'test_cluster' as a cluster name.

===Create metadata servers (MDS)===

Log in to the computers you want to configure as a metadata server as root.

To create the cluster and the very first MDS type:

 pstorage -c test_cluster make-mds -I -a 10.30.100.101 -r /pstorage/test_cluster-mds -p

This command creates new Parallels Cloud Storage cluster and metadata server and configures the IP address of ''10.30.100.101'' for communication with this server (replace ''10.30.100.101'' with IP address of your own MDS server). MDS will store its data at location specified by '''-r''' option. The command will also ask you to enter the password for authentication in your cluster.

After you have created the MDS server, start the MDS management service ('''pstorage-mdsd''') and configure it to start automatically when the server boots:

 service pstorage-mdsd start
 chkconfig pstorage-mdsd on


To create 2nd and subsequent MDS services on other nodes do:

1. Login to the node as root.

2. Setup cluster discovery. Normally, all the Pstorage components should be capable to discover each other on the network using multicast discovery (mDNS). This may not work however in Virtual Machines or if your network doesn't support multicasts. In this case you need to setup an MDS bootstrap list on the nodes manually. To do so create the '''bs.list''' file in the '''/etc/pstorage/clusters/<cluster_name>''' directory (make this directory if it does not exist) on the server you are configuring for the cluster and specify IP addresses and ports of the MDS servers in the cluster.
For example to create a bootstrap list for above cluster created type:
 echo "10.30.100.101:2510" >> /etc/pstorage/clusters/test_cluster/bs.list
Now future Pstorage services started on this machine will be able to discover other parties.

3. Authenticate the server in the cluster and add a new MDS to the cluster using similar to the above make-mds command w/o -I and -p options:
 pstorage -c test_cluster auth-node
 pstorage -c test_cluster make-mds -a 10.30.100.102 -r /pstorage/test_cluster-mds

===Create chunk server (CS)===

Log in to the computer you want to configure as a chunk server as root.
Note, you may need to setup a bootstrap list as described above in case cluster auto-discovery doesn't work.

Authenticate the server in the cluster (skip this step if configured MDS or CS already on that server):
 pstorage -c test_cluster auth-node

The command will ask you the password that you specified when setting up the first MDS server.

Create CS:
 pstorage -c test_cluster make-cs -r /pstorage/test_cluster-cs

This command will create a CS service and use the directory specified after '''-r''' option for CS data store.
After you have created the chunk server, start is as a service ('''pstorage-csd''') and configure it to start automatically when the machine boots:

 service pstorage-csd start
 chkconfig pstorage-csd on

===Setting up a client===

Log in to the computer you want to act as a client as root.
Note, you may need to setup a bootstrap list as described above in case cluster auto-discovery doesn't work.

Authenticate the server in the cluster (skip this step if configured MDS or CS already on that server):

 pstorage -c test_cluster auth-node

The command will ask you the password that you specified when setting up the first MDS server.

Create the directory to mount the Parallels Cloud Storage cluster to and then mount it as a conventional file system:

 mkdir -p /pcs
 pstorage-mount -c test_cluster /pcs

You may want to add this mount to /etc/fstab to make it happen automatically on node reboot. Consult ''man pstorage-mount'' for more details.

Now you can access your data from all the client machines and ready to run containers!

===Create a container running in the cluster===

Running a container over Pstrage is no different from any other local file system, so below example is just for the reference.
Log in to the computer running OpenVZ and that you have configured to act as a client for the Parallels Cloud Storage cluster.

Load OpenVZ ploop kernel modules if they aren't loaded yet:

 modprobe ploop pfmt_ploop1 pio_kaio

Mount Pstorage cluster at '''/pcs''' as described above if not done yet. Create a folder on Pstorage for the containers:
 mkdir -p /pcs/containers

Create a ploop-based container with CTID=101 (put your own template name below):
 vzctl create 101 --layout ploop --ostemplate centos-6-x86_64 --private /pcs/containers/

Now container with CTID=101 is ready for use and can be started on any Pstorage client node:
 vzctl start 101

In order to quickly relocate the container to another node (w/o data migration), just stop and unregister it on source node, then register and start on destination.

==Upgrading to Parallels Cloud Server==
What is [http://www.parallels.com/products/pcs/ Parallels Cloud Server]? Parallels Cloud Server is a unique virtualization server platform combining hypervisor & containers virtualization together with innovative storage virtualization [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Datasheets/ParCloudServer6_DataSheet_EN_Ltr_111312.pdf].

Please request more information on upgrading to Parallels Cloud Server on a [http://www.parallels.com/products/pcs/ product page] (see '''Request Information''' button).

==Pstorage Links & Documentation==
* Parallels Cloud Server [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Datasheets/ParCloudServer6_DataSheet_EN_Ltr_111312.pdf product datasheet].
* Parallels Cloud Storage [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Datasheets/ParCloudStorage_DataSheet_EN_Ltr_02262013.pdf product datascheet].
* For more information on setting up pstorage cluster please refer to the Parallels Cloud Storage documentation [http://download.parallels.com/doc/pcs/pdf/Parallels_Cloud_Storage.pdf].
* Pstroage performance whitepaper [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Whitepapers/PCloudStorage_Performance_Results_WP_EN_Ltr_02192013_web.pdf].
* YouTube introduction video [http://www.youtube.com/watch?v=6oEzW9w-1rg]
@@ Line 1: / Line 1: @@
-'''Virtuozzo Storage''' is a highly-available distributed storage (virtual SAN) with built-in replication and disaster recovery.
+= Parallels Cloud Storage (Pstorage) =
-Virtuozzo Storage provides a storage virtualization platform on top of commodity hardware with locally attached hard drives and enables the unification of storage into a cluster in scenarios like virtualization with the help of virtual machines (VMs) and/or Containers ([[CT]]s). Pstorage ensures a fast live migration of VMs and CTs across hardware nodes, without the need to copy VM/CT data, and high availability as the storage becomes available remotely.
+Parallels Storage (Pstorage) is a highly-available distributed storage (virtual SAN) with built-in replication and disaster recovery. Pstorage provides a storage virtualization platform on top of commodity hardware with locally attached hard drives and enables the unification of storage into a cluster in scenarios like virtualization with the help of virtual machines (VMs) and/or Containers (CTs). Pstorage ensures a fast live migration of VMs and CTs across hardware nodes, without the need to copy VM/CT data, and high availability as the storage becomes available remotely.
-== Features ==
+The main Pstorage features are listed below:
-<br clear="both">
-[[File:Parallels_Cloud_Storage_is_a_software_defined_storage.png|300px|right|link=http://www.youtube.com/watch?v=6oEzW9w-1rg|Virtuozzo Storage is a software defined storage]]
-The main Virtuozzo Storage features are listed below:
 * No special hardware requirements. Commodity hardware (SATA/SAS drives, 1Gbit+ Ethernet) can be used to create a storage.
 * Strong consistency semantics. This makes Pstorage suitable for iSCSI, VMs and CTs running on top of it (unlike object storage such as Amazon S3 or Swift).
-* Usable for Containers or exportable as iSCSI, NFS, S3 object storage
 * Built-in replication.
 * Automatic disaster recovery on hard drive or node failures.
@@ Line 20: / Line 16: @@
 * More uniform hardware performance and capacity utilization across the nodes, so overutilized nodes benefit from idle ones.
 * High performance - comparable to SAN.
 See a brief [http://www.youtube.com/watch?v=6oEzW9w-1rg video on YouTube].
-<br clear="both">
-== Pstorage for OpenVZ limitations ==
-{{Warning|
-* Virtuozzo Storage is available as a TECHNOLOGY PREVIEW ONLY for OpenVZ users and can't be licensed for production.
-* To unlock for running in production, you should upgrade to a full [[Virtuozzo]] product (see below).
-* Maximum capacity limited for usage in technology preview mode is 100 GB of logical (usable by containers) disk space.
-* After hitting this limit, writers can get blocked w/o errors expecting for a limit to be extended, so please avoid hitting the limit (it's not a bug :) ).
-}}
-=== Components ===
+==OpenVZ limitations==
+<span style="color:#FF0000">Parallels Cloud Storage is available as a TECHNOLOGY PREVIEW ONLY for OpenVZ users and can't be licensed for production.<br>To unlock for running in production you should upgrade to a full Parallels Cloud Server product (see below).<br>Maximum capacity limited for usage in technology preview mode is 100GB of logical (Containers usable) disk space.<br>After hitting this limit writers can get blocked w/o errors expecting for a limit to be extended, so please avoid hitting the limit (it's not a bug :) ).</span>
-[[File:Parallels_Cloud_Storage_components.png|650px|top|Virtuozzo Storage Components]]
+==Pstorage components==
+Any Pstorage includes three components:
-Any Virtuozzo Storage includes three components:
 * Metadata server (MDS). MDSs manage metadata, like file names, and keep control over how files are split into chunks and where the chunks are stored. They also track versions of chunks and ensure that the cluster has enough replicas. An MDS can be run in multiple instances to provide high availability. Besides, MDSs keep a global log of important events that happen in the cluster.
 * Chunk server (CS). A CS is a service responsible for storing real user data chunks and providing access to these data. A Pstorage cluster must have multiple instances of CSs for high availability.
+* Clients. Clients access a Pstorage cluster by communicating with MDSs and CSs. Parallels Containers and virtual machines can be run natively, i.e. directly from the Pstorage cluster. An additional Pstorage client -  can be used to mount Pstorage as a conventional file system (though Pstorage is not POSIX-compliant). Besides, Pstorage files can be mounted as a block device using the "ploop" feature and formatted as ext4 file system for other needs.
-* Clients. Clients access a Virtuozzo Storage cluster by communicating with MDSs and CSs. Virtuozzo Containers and virtual machines can be run natively, i.e. directly from the Virtuozzo Storage cluster. An additional Virtuozzo Storage client -  can be used to mount Virtuozzo Storage as a conventional file system (though Pstorage is not POSIX-compliant). Besides, Pstorage files can be mounted as a block device using the "ploop" feature and formatted as ext4 file system for other needs.
 A recommended cluster setup includes from 3 to 5 MDS instances (allowing you to survive the loss of 1 or 2 of MDSs, respectively) and multiple CSs providing storage capacity.
-== Setup ==
-This HOWTO explains how to setup Virtuozzo Storage cluster and run OpenVZ containers stored there. Please note, that it's just a brief HOWTO for quick and easy evaluation of Virtuozzo Storage (configuring only 1x MDS and CS service) and is not a real manual. We highly recommend to consult [http://download.parallels.com/doc/pcs/pdf/Parallels_Cloud_Storage.pdf Pstorage manual] and man pages (such as pstorage, pstorage-make-cs, pstorage-make-mds etc.) as it contain a lot of important details on types of SSD drives supported, what are the recommended configurations, how to configure big clusters with failure domains and so on.
-=== Installing Virtuozzo Storage software ===
-In order to install Pstorage RPM packages, log in as root to all the machines planned to be added to the cluster and perform the following actions.
+=Pstorage setup HOWTO=
+Below HOWTO explains how to setup Parallels Cloud Storage (Pstorage) cluster and run OpenVZ containers stored there. Please note, that it's just a brief HOWTO for quick and easy evaluation of Parallels Cloud Storage (configuring only 1x MDS and CS service) and is not a real manual. We highly recommend to consult [http://download.parallels.com/doc/pcs/pdf/Parallels_Cloud_Storage.pdf Pstorage manual] and man pages (such as pstorage, pstorage-make-cs, pstorage-make-mds etc.) as it contain a lot of important details on types of SSD drives supported, what are the recommended configurations, how to configure big clusters with failure domains and so on.
-Set up pstorage yum repository:
+==Installing Parallels Cloud Storage software==
- cat << EOF > /etc/yum.repos.d/pstorage.repo
+In order to install Pstorage RPM packages log in as root to all the machines planned to be added to the cluster and perform the following actions.
- [openvz-pstorage]
- name=Virtuozzo Storage for OpenVZ
- baseurl=http://download.openvz.org/pstorage/current
- enabled=1
- gpgcheck=0
- EOF
-Install needed packages:
+Download and install the following RPM packages: pstorage-ctl, pstorage-libs-shared, pstorage-metadata-server, pstorage-chunk-server and pstorage-client. These packages can be downloaded from http://download.openvz.org/pstorage:
-  yum install pstorage-metadata-server pstorage-chunk-server pstorage-client
+ wget http://download.openvz.org/pstorage/*
+  yum install pstorage-ctl pstorage-libs-shared pstorage-metadata-server pstorage-chunk-server pstorage-client
-=== Creating a cluster ===
+==Creating a cluster==
 Every Pstorage cluster has a unique cluster name used for remote service discovery and during authorization.
 So choose a name for the cluster that will uniquely identify it among other clusters in your network and avoid reusing it on cluster recreate. A name may contain the characters a-z, A-Z, 0-9, dash (-), and underscore (_). Here we will use 'test_cluster' as a cluster name.
-==== Create metadata servers (MDS) ====
+===Create metadata servers (MDS)===
 Log in to the computers you want to configure as a metadata server as root.
@@ Line 82: / Line 58: @@
   pstorage -c test_cluster make-mds -I -a 10.30.100.101 -r /pstorage/test_cluster-mds -p
-This command creates new Virtuozzo Storage cluster and metadata server and configures the IP address of ''10.30.100.101'' for communication with this server (replace ''10.30.100.101'' with IP address of your own MDS server). MDS will store its data at location specified by '''-r''' option. The command will also ask you to enter the password for authentication in your cluster.
+This command creates new Parallels Cloud Storage cluster and metadata server and configures the IP address of ''10.30.100.101'' for communication with this server (replace ''10.30.100.101'' with IP address of your own MDS server). MDS will store its data at location specified by '''-r''' option. The command will also ask you to enter the password for authentication in your cluster.
 After you have created the MDS server, start the MDS management service ('''pstorage-mdsd''') and configure it to start automatically when the server boots:
@@ Line 89: / Line 65: @@
   chkconfig pstorage-mdsd on
-To create a 2nd and subsequent MDS services on other nodes, do the following:
+To create 2nd and subsequent MDS services on other nodes do:
 . Login to the node as root.
@@ Line 102: / Line 79: @@
   pstorage -c test_cluster make-mds -a 10.30.100.102 -r /pstorage/test_cluster-mds
-==== Create a chunk server (CS) ====
+===Create chunk server (CS)===
 Log in to the computer you want to configure as a chunk server as root.
@@ Line 112: / Line 89: @@
 The command will ask you the password that you specified when setting up the first MDS server.
-Create a CS:
+Create CS:
   pstorage -c test_cluster make-cs -r /pstorage/test_cluster-cs
@@ Line 122: / Line 98: @@
   chkconfig pstorage-csd on
-==== Setting up a client ====
+===Setting up a client===
 Log in to the computer you want to act as a client as root.
@@ Line 133: / Line 109: @@
 The command will ask you the password that you specified when setting up the first MDS server.
-Create the directory to mount the Virtuozzo Storage cluster to and then mount it as a conventional file system:
+Create the directory to mount the Parallels Cloud Storage cluster to and then mount it as a conventional file system:
   mkdir -p /pcs
@@ Line 142: / Line 118: @@
 Now you can access your data from all the client machines and ready to run containers!
-==== Create a container running in the cluster ====
+===Create a container running in the cluster===
 Running a container over Pstrage is no different from any other local file system, so below example is just for the reference.
-Log in to the computer running OpenVZ and that you have configured to act as a client for the Virtuozzo Storage cluster.
+Log in to the computer running OpenVZ and that you have configured to act as a client for the Parallels Cloud Storage cluster.
 Load OpenVZ ploop kernel modules if they aren't loaded yet:
@@ Line 155: / Line 131: @@
 Create a ploop-based container with CTID=101 (put your own template name below):
-  vzctl create 101 --layout ploop --ostemplate centos-6-x86_64 --private /pcs/containers/101
+  vzctl create 101 --layout ploop --ostemplate centos-6-x86_64 --private /pcs/containers/
-Now container with CTID=101 is ready for use and can be started on '''any''' Pstorage client node (note, however, that you need to register container first if want to run on node different from creator one):
+Now container with CTID=101 is ready for use and can be started on any Pstorage client node:
   vzctl start 101
 In order to quickly relocate the container to another node (w/o data migration), just stop and unregister it on source node, then register and start on destination.
-== Upgrading to Virtuozzo ==
+==Upgrading to Parallels Cloud Server==
+What is [http://www.parallels.com/products/pcs/ Parallels Cloud Server]? Parallels Cloud Server is a unique virtualization server platform combining hypervisor & containers virtualization together with innovative storage virtualization [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Datasheets/ParCloudServer6_DataSheet_EN_Ltr_111312.pdf].
-'''[http://www.odin.com/products/virtuozzo/ Virtuozzo]''' is a unique virtualization server platform combining both hypervisor and container-based virtualization together with innovative storage virtualization.
-Please request more information on upgrading to Virtuozzo at the [http://www.odin.com/products/virtuozzo/ product page] (look for '''Request Information''' button).
-== External links ==
-* [http://www.odin.com/fileadmin/media/hcap/pcs/documents/ParCloudServer6_DataSheet_EN_Ltr_111312.pdf Virtuozzo product datasheet]
+Please request more information on upgrading to Parallels Cloud Server on a [http://www.parallels.com/products/pcs/ product page] (see '''Request Information''' button).
-* [http://www.odin.com/fileadmin/media/hcap/pcs/documents/ParCloudStorage_DataSheet_EN_Ltr_02262013.pdf Parallels Cloud Storage product datasheet]
-* [http://download.parallels.com/doc/pcs/pdf/Parallels_Cloud_Storage_Administrators_Guide.pdf Parallels Cloud Storage Administrator's Guide]
-* [http://www.odin.com/fileadmin/media/hcap/pcs/documents/PCloudStorage_Performance_Results_WP_EN_Ltr_02192013_web.pdf Pstorage performance whitepaper]
-* [http://www.youtube.com/watch?v=6oEzW9w-1rg Pstorage introduction video]
-[[Category: Storage]]
+==Pstorage Links & Documentation==
+* Parallels Cloud Server [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Datasheets/ParCloudServer6_DataSheet_EN_Ltr_111312.pdf product datasheet].
+* Parallels Cloud Storage [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Datasheets/ParCloudStorage_DataSheet_EN_Ltr_02262013.pdf product datascheet].
+* For more information on setting up pstorage cluster please refer to the Parallels Cloud Storage documentation [http://download.parallels.com/doc/pcs/pdf/Parallels_Cloud_Storage.pdf].
+* Pstroage performance whitepaper [http://www.parallels.com/fileadmin/parallels/documents/hosting-cloud-enablement/pcs/Production_Whitepapers/PCloudStorage_Performance_Results_WP_EN_Ltr_02192013_web.pdf].
+* YouTube introduction video [http://www.youtube.com/watch?v=6oEzW9w-1rg]