Managing Quotas

This guide will show you how to set the usage quotas for users and groups.

Overview

The quota system tracks user and group usage of system resources, and allows the system administrator to set limits on the usage of these resources. Quota limits can be set for:

  • users, to individually limit the usage made by a given user.
  • groups, to limit the overall usage made by all the users in a given group. This can be of special interest for the OpenNebula Zones and Virtual Data Center (VDC) components.

Which Resource can be limited?

The quota system allows you to track and limit usage on:

  • Datastores, to control the amount of storage capacity allocated to each user/group for each datastore.
  • Compute, to limit the overall memory, cpu or VM instances.
  • Network, to limit the number of IPs a user/group can get from a given network. This is specially interesting for networks with public IPs, which usually are a limited resource.
  • Images, you can limit the how many VM instances from a given user/group are using a given image. You can take advantage of this quota when the image contains consumable resources (e.g. software licenses).

Warning

Only datastore size is consumed when using a Ceph backend, system disks will not be affected in this case. The reason is that this kind of datastores use the same space for system and for images, so OpenNebula can not know which space is used in each case.

Defining User/Group Quotas

Usage quotas are set in a traditional template syntax (either plain text or XML). The following table explains the attributes needed to set each quota:

Datastore Quotas. Attribute name: DATASTORE

DATASTORE Attribute Description
ID ID of the Datastore to set the quota for
SIZE Maximum size in MB that can be used in the datastore
IMAGE Maximum number of images that can be created in the datastore

Compute Quotas. Attribute name: VM

VM Attribute Description
VMS Maximum number of VMs that can be created
MEMORY Maximum memory in MB that can be requested by user/group VMs
CPU Maximum CPU capacity that can be requested by user/group VMs
RUNNING VMS Maximum number of VMs that can be running
RUNNING MEMORY Maximum memory in MB that can be running by user/group VMs
RUNNING CPU Maximum CPU capacity that can be running by user/group VMs
SYSTEM_DISK_SIZE Maximum size (in MB) of system disks that can be requested by user/group VMs

Note

Running quotas will be increased or decreased depending on the state of the Virtual Machine. The states in which the machine is counted as ACTIVE “Running” are ACTIVE , HOLD, PENDING and CLONING.

Network Quotas. Attribute name: NETWORK

NETWORK Attribute Description
ID ID of the Network to set the quota for
LEASES Maximum IPs that can be leased from the Network

Image Quotas. Attribute name: IMAGE

IMAGE Attribute Description
ID ID of the Image to set the quota for
RVMS Maximum VMs that can used this image at the same time

For each quota, there are two special limits:

  • -1 means that the default quota will be used
  • -2 means unlimited

Warning

Each quota has an usage counter associated named <QUOTA_NAME>_USED. For example MEMORY_USED means the total memory used by user/group VMs, and its associated quota is MEMORY.

The following template shows a quota example for a user in plain text. It limits the overall usage in Datastore 0 to 20Gb (for an unlimited number of images); the number of VMs that can be created to 4 with a maximum memory to 2G and 5 CPUs; the number of leases from network 1 to 4; and image 1 can only be used by 3 VMs at the same time:

DATASTORE=[
  ID="1",
  IMAGES="-2",
  SIZE="20480"
]

VM=[
  CPU="5",
  MEMORY="2048",
  VMS="4",
  SYSTEM_DISK_SIZE="-1"
]

NETWORK=[
  ID="1",
  LEASES="4"
]

IMAGE=[
  ID="1",
  RVMS="3"
]

IMAGE=[
  ID="2",
  RVMS="-2"
]

Warning

Note that whenever a network, image, datastore or VM is used the corresponding quota counters are created for the user with an unlimited value. This allows to track the usage of each user/group even when quotas are not used.

Setting User/Group Quotas

User/group quotas can be easily set up either trough the command line interface or Sunstone. Note that you need MANAGE permissions to set a quota of user, and ADMIN permissions to set the quota of a group. In this way, by default, only oneadmin can set quotas for a group, but if you define a group manager she can set specific usage quotas for the users on her group (so distributing resources as required). You can always change this behavior setting the appropriate ACL rules.

To set the quota for a user, e.g. userA, just type:

oneuser quota userA

This will open an editor session to edit a quota template (with some tips about the syntax).

Warning

Usage metrics are included for information purposes (e.g. CPU_USED, MEMORY_USED, LEASES_USED...) you cannot modify them

Warning

You can add as many resource quotas as needed even if they have not been automatically initialized.

Similarly, you can set the quotas for group A with:

onegroup quota groupA

There is a batchquota command that allows you to set the same quotas for several users or groups:

oneuser batchquota userA,userB,35
onegroup batchquota 100..104

You can also set the user/group quotas in Sunstone through the user/group tab.

image1

image2

Setting Default Quotas

There are two default quota limit templates, one for users and another for groups. This template applies to all users/groups, unless they have an individual limit set.

Use the oneuser/onegroup defaultquota command.

oneuser defaultquota

Checking User/Group Quotas

Quota limits and usage for each user/group is included as part of its standard information, so it can be easily check with the usual commands. Check the following examples:

oneuser show uA
USER 2 INFORMATION
ID             : 2
NAME           : uA
GROUP          : gA
PASSWORD       : a9993e364706816aba3e25717850c26c9cd0d89d
AUTH_DRIVER    : core
ENABLED        : Yes

USER TEMPLATE


VMS USAGE & QUOTAS

          VMS               MEMORY                  CPU     SYSTEM_DISK_SIZE
  1 /       4        1M /        -      2.00 /        -        0M /        -

VMS USAGE & QUOTAS - RUNNING

    RUNNING VMS       RUNNING MEMORY          RUNNING CPU
    1 /       -        1M /       2M      2.00 /        -

DATASTORE USAGE & QUOTAS

NETWORK USAGE & QUOTAS

IMAGE USAGE & QUOTAS

And for the group:

onegroup show gA
GROUP 100 INFORMATION
ID             : 100
NAME           : gA

USERS
ID
2
3

VMS USAGE & QUOTAS

          VMS               MEMORY                  CPU     SYSTEM_DISK_SIZE
  1 /       4        1M /        -      2.00 /        -        0M /        -

VMS USAGE & QUOTAS - RUNNING

    RUNNING VMS       RUNNING MEMORY          RUNNING CPU
    1 /       -        1M /       2M      2.00 /        -

DATASTORE USAGE & QUOTAS

NETWORK USAGE & QUOTAS

IMAGE USAGE & QUOTAS

This information is also available through Sunstone as part of the user/group information.