pve-intro.adoc

   1 Introduction
   2 ============
   3
   4 {pve} is a platform to run virtual machines and containers. It is
   5 based on Debian Linux, and completely open source. For maximum
   6 flexibility, we implemented two virtualization technologies -
   7 Kernel-based Virtual Machine (KVM) and container-based virtualization
   8 (LXC).
   9
  10 One main design goal was to make administration as easy as
  11 possible. You can use {pve} on a single node, or assemble a cluster of
  12 many nodes. All management tasks can be done using our web-based
  13 management interface, and even a novice user can setup and install
  14 {pve} within minutes.
  15
  16 image::images/pve-software-stack.svg["Proxmox Software Stack",align="center"]
  17
  18
  19 Central Management
  20 ------------------
  21
  22 While many people start with a single node, {pve} can scale out to a
  23 large set of clustered nodes. The cluster stack is fully integrated
  24 and ships with the default installation.
  25
  26 Unique Multi-Master Design::
  27
  28 The integrated web-based management interface gives you a clean
  29 overview of all your KVM guests and Linux containers and even of your
  30 whole cluster. You can easily manage your VMs and containers, storage
  31 or cluster from the GUI. There is no need to install a separate,
  32 complex, and pricey management server.
  33
  34 Proxmox Cluster File System (pmxcfs)::
  35
  36 Proxmox VE uses the unique Proxmox Cluster file system (pmxcfs), a
  37 database-driven file system for storing configuration files. This
  38 enables you to store the configuration of thousands of virtual
  39 machines. By using corosync, these files are replicated in real time
  40 on all cluster nodes. The file system stores all data inside a
  41 persistent database on disk, nonetheless, a copy of the data resides
  42 in RAM which provides a maximum storage size is 30MB - more than
  43 enough for thousands of VMs.
  44 +
  45 Proxmox VE is the only virtualization platform using this unique
  46 cluster file system.
  47
  48 Web-based Management Interface::
  49
  50 Proxmox VE is simple to use. Management tasks can be done via the
  51 included web based management interface - there is no need to install a
  52 separate management tool or any additional management node with huge
  53 databases. The multi-master tool allows you to manage your whole
  54 cluster from any node of your cluster. The central web-based
  55 management - based on the JavaScript Framework (ExtJS) - empowers
  56 you to control all functionalities from the GUI and overview history
  57 and syslogs of each single node. This includes running backup or
  58 restore jobs, live-migration or HA triggered activities.
  59
  60 Command Line::
  61
  62 For advanced users who are used to the comfort of the Unix shell or
  63 Windows Powershell, Proxmox VE provides a command line interface to
  64 manage all the components of your virtual environment. This command
  65 line interface has intelligent tab completion and full documentation
  66 in the form of UNIX man pages.
  67
  68 REST API::
  69
  70 Proxmox VE uses a RESTful API. We choose JSON as primary data format,
  71 and the whole API is formally defined using JSON Schema. This enables
  72 fast and easy integration for third party management tools like custom
  73 hosting environments.
  74
  75 Role-based Administration::
  76
  77 You can define granular access for all objects (like VMs, storages,
  78 nodes, etc.) by using the role based user- and permission
  79 management. This allows you to define privileges and helps you to
  80 control access to objects. This concept is also known as access
  81 control lists: Each permission specifies a subject (a user or group)
  82 and a role (set of privileges) on a specific path.
  83
  84 Authentication Realms::
  85
  86 Proxmox VE supports multiple authentication sources like Microsoft
  87 Active Directory, LDAP, Linux PAM standard authentication or the
  88 built-in Proxmox VE authentication server.
  89
  90
  91 Flexible Storage
  92 ----------------
  93
  94 The Proxmox VE storage model is very flexible. Virtual machine images
  95 can either be stored on one or several local storages or on shared
  96 storage like NFS and on SAN. There are no limits, you may configure as
  97 many storage definitions as you like. You can use all storage
  98 technologies available for Debian Linux.
  99
 100 One major benefit of storing VMs on shared storage is the ability to
 101 live-migrate running machines without any downtime, as all nodes in
 102 the cluster have direct access to VM disk images.
 103
 104 We currently support the following Network storage types:
 105
 106 * LVM Group (network backing with iSCSI targets)
 107 * iSCSI target
 108 * NFS Share
 109 * Ceph RBD
 110 * Directly use iSCSI LUNs
 111 * GlusterFS
 112
 113 Local storage types supported are:
 114
 115 * LVM Group (local backing devices like block devices, FC devices, DRBD, etc.)
 116 * Directory (storage on existing filesystem)
 117 * ZFS
 118
 119
 120 Integrated Backup and Restore
 121 -----------------------------
 122
 123 The integrated backup tool (`vzdump`) creates consistent snapshots of
 124 running Containers and KVM guests. It basically creates an archive of
 125 the VM or CT data which includes the VM/CT configuration files.
 126
 127 KVM live backup works for all storage types including VM images on
 128 NFS, iSCSI LUN, Ceph RBD or Sheepdog. The new backup format is
 129 optimized for storing VM backups fast and effective (sparse files, out
 130 of order data, minimized I/O).
 131
 132
 133 High Availability Cluster
 134 -------------------------
 135
 136 A multi-node Proxmox VE HA Cluster enables the definition of highly
 137 available virtual servers. The Proxmox VE HA Cluster is based on
 138 proven Linux HA technologies, providing stable and reliable HA
 139 services.
 140
 141
 142 Flexible Networking
 143 -------------------
 144
 145 Proxmox VE uses a bridged networking model. All VMs can share one
 146 bridge as if virtual network cables from each guest were all plugged
 147 into the same switch. For connecting VMs to the outside world, bridges
 148 are attached to physical network cards assigned a TCP/IP
 149 configuration.
 150
 151 For further flexibility, VLANs (IEEE 802.1q) and network
 152 bonding/aggregation are possible. In this way it is possible to build
 153 complex, flexible virtual networks for the Proxmox VE hosts,
 154 leveraging the full power of the Linux network stack.
 155
 156
 157 Integrated Firewall
 158 -------------------
 159
 160 The integrated firewall allows you to filter network packets on
 161 any VM or Container interface. Common sets of firewall rules can
 162 be grouped into ``security groups''.
 163
 164
 165 Why Open Source
 166 ---------------
 167
 168 Proxmox VE uses a Linux kernel and is based on the Debian GNU/Linux
 169 Distribution. The source code of Proxmox VE is released under the
 170 http://www.gnu.org/licenses/agpl-3.0.html[GNU Affero General Public
 171 License, version 3]. This means that you are free to inspect the
 172 source code at any time or contribute to the project yourself.
 173
 174 At Proxmox we are committed to use open source software whenever
 175 possible. Using open source software guarantees full access to all
 176 functionalities - as well as high security and reliability. We think
 177 that everybody should have the right to access the source code of a
 178 software to run it, build on it, or submit changes back to the
 179 project. Everybody is encouraged to contribute while Proxmox ensures
 180 the product always meets professional quality criteria.
 181
 182 Open source software also helps to keep your costs low and makes your
 183 core infrastructure independent from a single vendor.
 184
 185
 186 Your benefit with {pve}
 187 -----------------------
 188
 189 * Open source software
 190 * No vendor lock-in
 191 * Linux kernel
 192 * Fast installation and easy-to-use
 193 * Web-based management interface
 194 * REST API
 195 * Huge active community
 196 * Low administration costs and simple deployment
 197
 198
 199 Project History
 200 ---------------
 201
 202 The project started in 2007, followed by a first stable version in
 203 2008. At the time we used OpenVZ for containers, and KVM for virtual
 204 machines. The clustering features were limited, and the user interface
 205 was simple (server generated web page).
 206
 207 But we quickly developed new features using the
 208 http://corosync.github.io/corosync/[Corosync] cluster stack, and the
 209 introduction of the new Proxmox cluster file system (pmxcfs) was a big
 210 step forward, because it completely hides the cluster complexity from
 211 the user. Managing a cluster of 16 nodes is as simple as managing a
 212 single node.
 213
 214 We also introduced a new REST API, with a complete declarative
 215 specification written in JSON-Schema. This enabled other people to
 216 integrate {pve} into their infrastructure, and made it easy to provide
 217 additional services.
 218
 219 Also, the new REST API made it possible to replace the original user
 220 interface with a modern HTML5 application using JavaScript. We also
 221 replaced the old Java based VNC console code with
 222 https://kanaka.github.io/noVNC/[noVNC]. So you only need a web browser
 223 to manage your VMs.
 224
 225 The support for various storage types is another big task. Notably,
 226 {pve} was the first distribution to ship ZFS on Linux by default in
 227 2014. Another milestone was the ability to run and manage
 228 http://ceph.com/[Ceph] storage on the hypervisor nodes. Such setups
 229 are extremely cost effective.
 230
 231 When we started we were among the first companies providing
 232 commercial support for KVM. The KVM project itself continuously
 233 evolved, and is now a widely used hypervisor. New features arrive
 234 with each release. We developed the KVM live backup feature, which
 235 makes it possible to create snapshot backups on any storage type.
 236
 237 The most notable change with version 4.0 was the move from OpenVZ to
 238 https://linuxcontainers.org/[LXC]. Containers are now deeply
 239 integrated, and they can use the same storage and network features
 240 as virtual machines.