1.5. MAC Address Pools

MAC address pools define the range(s) of MAC addresses allocated for each cluster. A MAC address pool is specified for each cluster. By using MAC address pools, Red Hat Virtualization can automatically generate and assign MAC addresses to new virtual network devices, which helps to prevent MAC address duplication. MAC address pools are more memory efficient when all MAC addresses related to a cluster are within the range for the assigned MAC address pool.

The same MAC address pool can be shared by multiple clusters, but each cluster has a single MAC address pool assigned. A default MAC address pool is created by Red Hat Virtualization and is used if another MAC address pool is not assigned. For more information about assigning MAC address pools to clusters see Section 5.2.1, “Creating a New Cluster”.

Note

If more than one Red Hat Virtualization cluster shares a network, do not rely solely on the default MAC address pool because the virtual machines of each cluster will try to use the same range of MAC addresses, leading to conflicts. To avoid MAC address conflicts, check the MAC address pool ranges to ensure that each cluster is assigned a unique MAC address range.

The MAC address pool assigns the next available MAC address following the last address that was returned to the pool. If there are no further addresses left in the range, the search starts again from the beginning of the range. If there are multiple MAC address ranges with available MAC addresses defined in a single MAC address pool, the ranges take turns in serving incoming requests in the same way available MAC addresses are selected.

1.5.1. Creating MAC Address Pools

You can create new MAC address pools.

Creating a MAC Address Pool

  1. Click AdministrationConfigure.
  2. Click the MAC Address Pools tab.
  3. Click Add.
  4. Enter the Name and Description of the new MAC address pool.
  5. Select the Allow Duplicates check box to allow a MAC address to be used multiple times in a pool. The MAC address pool will not automatically use a duplicate MAC address, but enabling the duplicates option means a user can manually use a duplicate MAC address.

    Note

    If one MAC address pool has duplicates disabled, and another has duplicates enabled, each MAC address can be used once in the pool with duplicates disabled but can be used multiple times in the pool with duplicates enabled.

  6. Enter the required MAC Address Ranges. To enter multiple ranges click the plus button next to the From and To fields.
  7. Click OK.

1.5.2. Editing MAC Address Pools

You can edit MAC address pools to change the details, including the range of MAC addresses available in the pool and whether duplicates are allowed.

Editing MAC Address Pool Properties

  1. Click AdministrationConfigure.
  2. Click the MAC Address Pools tab.
  3. Select the MAC address pool to be edited.
  4. Click Edit.
  5. Change the Name, Description, Allow Duplicates, and MAC Address Ranges fields as required.

    Note

    When a MAC address range is updated, the MAC addresses of existing NICs are not reassigned. MAC addresses that were already assigned, but are outside of the new MAC address range, are added as user-specified MAC addresses and are still tracked by that MAC address pool.

  6. Click OK.

1.5.3. Editing MAC Address Pool Permissions

After a MAC address pool has been created, you can edit its user permissions. The user permissions control which data centers can use the MAC address pool. See Section 1.1, “Roles” for more information on adding new user permissions.

Editing MAC Address Pool Permissions

  1. Click AdministrationConfigure.
  2. Click the MAC Address Pools tab.
  3. Select the required MAC address pool.
  4. Edit the user permissions for the MAC address pool:

    • To add user permissions to a MAC address pool:

      1. Click Add in the user permissions pane at the bottom of the Configure window.
      2. Search for and select the required users.
      3. Select the required role from the Role to Assign drop-down list.
      4. Click OK to add the user permissions.
    • To remove user permissions from a MAC address pool:

      1. Select the user permission to be removed in the user permissions pane at the bottom of the Configure window.
      2. Click Remove to remove the user permissions.

1.5.4. Removing MAC Address Pools

You can remove a created MAC address pool if the pool is not associated with a cluster, but the default MAC address pool cannot be removed.

Removing a MAC Address Pool

  1. Click AdministrationConfigure.
  2. Click the MAC Address Pools tab.
  3. Select the MAC address pool to be removed.
  4. Click the Remove.
  5. Click OK.