Cinder FC Zone Manager - User Friendly Zone Names

https://blueprints.launchpad.net/cinder/+spec/brocade-zone-driver-friendly-zone-names

Introduce user friendly names for zones to include host name and storage system along with ids to easily identify the host and storage port details.

Problem description

FC Zone Manager will be enhanced to configure friendly names for zones. At present, zone manager uses the WWNs of Adapter port and Target port to configure the zone names.

Use Cases

This addresses the need for zone names to be user friendly so that humans can easily read the name and understand what host and/or storage system is represented by that zone. This feature only has impact on volume driver developers that need to add the host name and storage system name into the connection info being passed to the FC zone manager if they wish to use this feature.

Proposed change

As per current design, the zone names include a default prefix ‘openstack’ which can be customized and host port wwn and target wwn (optional) based on the zoning_policy config option: initiator-target or initiator as follows:

Initiator-Target Zones:
<openstack><host WWPN><target WWPN>
Initiator Zones:
<openstack><host WWPN>

These names are not user friendly.

This proposal is to create friendly zone names with host and storage names as follows:

Initiator-target zones
<Host Name>_<host WWPN>_<storage System>_<target WWPN>
Initiator zones
<Host Name>_<host WWPN>

The required host name and storage system are populated in connection_info dictionary returned by fibre channel volume driver initialize_connection method call. The volume driver will extract the host name from the connector object passed as parameter to the initialize_connection method. This blueprint is not documenting the ways the volume driver fetch the storage system value. It is up to the volume driver to implement a mechanism to retrieve the storage system value.

Connection Info samples:

{
   'driver_volume_type': 'fibre_channel'
     'data': {
        **'storage_system': 'AMCE_Array',**
        **'host_name': 'OS_Host100',**
        'target_discovered': True,
        'target_lun': 1,
        'target_wwn': '1234567890123',
        'access_mode': 'rw'
     }
}

or:

{
   'driver_volume_type': 'fibre_channel'
     'data': {
        **'storage_system': 'AMCE_Array',**
        **'host_name': 'OS_Host100',**
        'target_discovered': True,
        'target_lun': 1,
        'target_wwn': ['1234567890123', '0987654321321'],
        'access_mode': 'rw'
     }
}

On attach/detach, Zone Manager will be initialized with connection_info which is provided by volume driver. Zone Manager in turn will extract the host name and storage system and will pass this information to the zone driver to create/delete friendly zone names.

There is a 64 characters limit for zone names. Hence zone driver implements a mechanism to normalize the host name and storage system to best fit the zone name. A WWN is 16 characters long and 32 characters are reserved for host and storage WWNs. For Initiator and Target policy, the max number of characters available for host name and storage system is 14 characters each. Zone driver will trim the names to a max of 14 characters. For Initiator only policy, the max size allowed for host name is 47 characters. Remaining characters are reserved for ‘_’.

Zone Driver updates:

Zone driver’s add_connection and delete_connection methods will be enhanced to take host and storage params. These names are defaulted to None. If names are None, then zone driver will fall back to existing naming mechanism.

The Zone manager will extract the host name and storage system from connection_info dictionary using host_name and storage_system keys. If keys are not found or None, then Zone manager will initialize host name and storage system local variables to None.

Alternatives

None.

Data model impact

None.

REST API impact

None.

Security impact

None.

Notifications impact

None.

Other end user impact

None.

Performance Impact

There is no noticeable performance impact provided FC volume driver will be able to fetch storage system value swiftly.

Other deployer impact

None.

Developer impact

FC Volume drivers need to enhance their existing drivers to support friendly zone names. This is optional.

The storage and host name in the connection_info object returned by the initialize_connection method of FC Volume driver. See the proposed change section above for details.

Implementation

Assignee(s)

Primary assignee:
Prakash Kaligotla
Other contributors:
Nagendra Rao Jaladanki Angela Smith

Work Items

  • Enhance the zone manager to pass connection_info object to zone driver.
  • Implement Brocade Zone Driver to create zones as per new format using the host name and storage system in the connector object.
  • Implement Cisco Zone Driver to create zones as per new format using the host name and storage system in the connector object.
  • Volume drivers are expected to add storage system information to connector object.
  • Unit test the zone driver and client code.

Dependencies

Has dependency on FC Volume Drivers to provide host name and storage system as part of connection_info return dictionary on attach/detach calls.

If driver does not provide host name and storage system, the existing zone naming mechanism will be used.

Testing

Attach/Detach unit tests will be performed to verify zone manager.

Documentation Impact

None.