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On Wed, May 31, 2023 at 10:44 AM Swogat Pradhan <swogatpradhan22 at gmail.com>
wrote:

> Hi Alan,
> Can you please check if the environment file attached is in correct format
> and how it should be?
> Also should i remove the old netapp environment file and use the new
> custom environment file created (attached).
>

You could retain the original environment file, and merge in just a portion
of the sample file that you attached.

The original file contains all the settings, including the
resource_registry entry, to deploy the first netapp
in the controlplane. You want to enhance this with just a couple of items
in order to deploy the second
netapp at the edge site.

The important thing to know is the CinderNetappMultiConfig entries are
necessary only for the second netapp.
The 'tripleo_netapp' entry could be removed, because it's basically taken
care of by the original env file. You
only need to include the 'tripleo_netapp_dcn02' settings. Furthermore, you
don't need to list every setting;
you only need to list the ones that differ from the settings in the
original env file. Basically, the settings in
the original env file (including the resource_registry) define the default
values for all netapp backends, and
the entries in the CinderNetappMultiConfig define the overrides for
specific backends. For example, if the
original env file sets "CinderNetappStorageProtocol: iscsi" then that will
be the default value for all netapp
backends, unless you override it in the CinderNetappMultiConfig section.

Lastly, your CinderNetappBackendName setting looks correct (it specifies
both the 'tripleo_netapp' and
'tripleo_netapp_dcn02' backends).

Alan


>
> With regards,
> Swogat Pradhan
>
> On Wed, May 31, 2023 at 10:46 PM Swogat Pradhan <swogatpradhan22 at gmail.com>
> wrote:
>
>> Hi Alan,
>> Thanks for your clarification, the way you suggested will solve my issue.
>> But i already have a netapp backend in my central site and to add another
>> backend should i follow this documentation:
>> https://access.redhat.com/documentation/en-us/red_hat_openstack_platform/17.0/html/custom_block_storage_back_end_deployment_guide/ref_configuration-sample-environment-file_custom-cinder-back-end
>>
>> And should i remove the old netapp environment file and use the new
>> custom environment file created using the above mentioned guide??
>>
>> I already have a prod workload in the currently deployed netapp and I do
>> not want to cause any issues in that netapp storage.
>>
>>
>> With regards,
>> Swogat Pradhan
>>
>> On Tue, May 30, 2023 at 8:43 PM Alan Bishop <abishop at redhat.com> wrote:
>>
>>>
>>>
>>> On Thu, May 25, 2023 at 9:39 PM Swogat Pradhan <
>>> swogatpradhan22 at gmail.com> wrote:
>>>
>>>> Hi Alan,
>>>> My netapp storage is located in edge site itself.
>>>> As the networks are routable my central site is able to reach the
>>>> netapp storage ip address (ping response is 30ms-40ms).
>>>> Let's say i included the netapp storage yaml in central site deployment
>>>> script (which is not recommended) and i am able to create the volumes as it
>>>> is reachable from controller nodes.
>>>> Will i be able to mount those volumes in edge site VM's?? And if i am
>>>> able to do so, then how will the data flow?? When storing something in the
>>>> netapp volume will the data flow through the central site controller and
>>>> get stored in the storage space?
>>>>
>>>
>>> A cinder-volume service running in the central site's controplane will
>>> be able to work with a netapp backend that's physically located at an edge
>>> site. The good news is the c-vol service will be HA because it will be
>>> controlled by pacemaker running on the controllers.
>>>
>>> In order for VMs at the edge site to access volumes on the netapp,
>>> you'll need to set the CinderNetappAvailabilityZone [1] to the edge site's
>>> AZ.
>>>
>>> [1]
>>> https://opendev.org/openstack/tripleo-heat-templates/src/branch/stable/wallaby/deployment/cinder/cinder-backend-netapp-puppet.yaml#L43
>>>
>>> To attach a netapp volume, nova-compute at the edge will interact with
>>> cinder-volume in the controlplane, and cinder-volume will in turn interact
>>> with the netapp. This will happen over central <=> edge network
>>> connections. Eventually, nova will directly connect to the netapp, so all
>>> traffic from the VM to the netapp will occur within the edge site. Data
>>> will not flow through the cinder-volume service, but there are restrictions
>>> and limitations:
>>> - Only that one edge site can access the netapp backend
>>> - If the central <=> edge network connection then you won't be able to
>>> attach or detach a netapp volume (but active connections will continue to
>>> work)
>>>
>>> Of course, there are operations where cinder services are in the data
>>> path (e.g. creating a volume from an image), but not when a VM is accessing
>>> a volume.
>>>
>>> Alan
>>>
>>>
>>>> With regards,
>>>> Swogat Pradhan
>>>>
>>>> On Fri, 26 May 2023, 10:03 am Alan Bishop, <abishop at redhat.com> wrote:
>>>>
>>>>>
>>>>>
>>>>> On Thu, May 25, 2023 at 12:09 AM Swogat Pradhan <
>>>>> swogatpradhan22 at gmail.com> wrote:
>>>>>
>>>>>> Hi Alan,
>>>>>> So, can I include the cinder-netapp-storage.yaml file in the central
>>>>>> site and then use the new backend to add storage to edge VM's?
>>>>>>
>>>>>
>>>>> Where is the NetApp physically located? Tripleo's DCN architecture
>>>>> assumes the storage is physically located at the same site where the
>>>>> cinder-volume service will be deployed. If you include the
>>>>> cinder-netapp-storage.yaml environment file in the central site's
>>>>> controlplane, then VMs at the edge site will encounter the problems I
>>>>> outlined earlier (network latency, no ability to do cross-AZ attachments).
>>>>>
>>>>>
>>>>>> I believe it is not possible right?? as the cinder volume in the edge
>>>>>> won't have the config for the netapp.
>>>>>>
>>>>>
>>>>> The cinder-volume services at an edge site are meant to manage storage
>>>>> devices at that site. If the NetApp is at the edge site, ideally you'd
>>>>> include some variation of the cinder-netapp-storage.yaml environment file
>>>>> in the edge site's deployment. However, then you're faced with the fact
>>>>> that the NetApp driver doesn't support A/A, which is required for c-vol
>>>>> services running at edge sites (In case you're not familiar with these
>>>>> details, tripleo runs all cinder-volume services in active/passive mode
>>>>> under pacemaker on controllers in the controlplane. Thus, only a single
>>>>> instance runs at any time, and pacemaker provides HA by moving the service
>>>>> to another controller if the first one goes down. However, pacemaker is not
>>>>> available at edge sites, and so to get HA, multiple instances of the
>>>>> cinder-volume service run simultaneously on 3 nodes (A/A), using etcd as a
>>>>> Distributed Lock Manager (DLM) to coordinate things. But drivers must
>>>>> specifically support running A/A, and the NetApp driver does NOT.)
>>>>>
>>>>> Alan
>>>>>
>>>>>
>>>>>> With regards,
>>>>>> Swogat Pradhan
>>>>>>
>>>>>> On Thu, May 25, 2023 at 2:17 AM Alan Bishop <abishop at redhat.com>
>>>>>> wrote:
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Wed, May 24, 2023 at 3:15 AM Swogat Pradhan <
>>>>>>> swogatpradhan22 at gmail.com> wrote:
>>>>>>>
>>>>>>>> Hi,
>>>>>>>> I have a DCN setup and there is a requirement to use a netapp
>>>>>>>> storage device in one of the edge sites.
>>>>>>>> Can someone please confirm if it is possible?
>>>>>>>>
>>>>>>>
>>>>>>> I see from prior email to this list that you're using tripleo, so
>>>>>>> I'll respond with that in mind.
>>>>>>>
>>>>>>> There are many factors that come into play, but I suspect the short
>>>>>>> answer to your question is no.
>>>>>>>
>>>>>>> Tripleo's DCN architecture requires the cinder-volume service
>>>>>>> running at edge sites to run in active-active
>>>>>>> mode, where there are separate instances running on three nodes in
>>>>>>> to for the service to be highly
>>>>>>> available (HA).The problem is that only a small number of cinder
>>>>>>> drivers support running A/A, and NetApp's
>>>>>>> drivers do not support A/A.
>>>>>>>
>>>>>>> It's conceivable you could create a custom tripleo role that deploys
>>>>>>> just a single node running cinder-volume
>>>>>>> with a NetApp backend, but it wouldn't be HA.
>>>>>>>
>>>>>>> It's also conceivable you could locate the NetApp system in the
>>>>>>> central site's controlplane, but there are
>>>>>>> extremely difficult constraints you'd need to overcome:
>>>>>>> - Network latency between the central and edge sites would mean the
>>>>>>> disk performance would be bad.
>>>>>>> - You'd be limited to using iSCSI (FC wouldn't work)
>>>>>>> - Tripleo disables cross-AZ attachments, so the only way for an edge
>>>>>>> site to access a NetApp volume
>>>>>>> would be to configure the cinder-volume service running in the
>>>>>>> controlplane with a backend availability
>>>>>>> zone set to the edge site's AZ. You mentioned the NetApp is needed
>>>>>>> "in one of the edge sites," but in
>>>>>>> reality the NetApp would be available in one, AND ONLY ONE edge
>>>>>>> site, and it would also not be available
>>>>>>> to any instances running in the central site.
>>>>>>>
>>>>>>> Alan
>>>>>>>
>>>>>>>
>>>>>>>> And if so then should i add the parameters in the edge deployment
>>>>>>>> script or the central deployment script.
>>>>>>>> Any suggestions?
>>>>>>>>
>>>>>>>> With regards,
>>>>>>>> Swogat Pradhan
>>>>>>>>
>>>>>>>
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