Include openstack manila driver related documentation

[Srinesh21]

Includes changes for Manila Driver

• Manila driver for HPE Alletra MP B10000
• External docs: https://docs.openstack.org/manila/latest/admin/hpe_alletra_mp_b10000_driver.html, https://docs.openstack.org/manila/latest/configuration/shared-file-systems/drivers/hpe-alletra-mp-b10000-driver.html

[jlothe]

Hi Srinesh,

I have couple of suggestions on the documentation part, please refer below:

1. Share size limits are missing

The docs should say how small or large a share can be.

The driver only allows shares from 1 GiB up to 64 TiB. If someone tries to create or extend a share outside that range, it will fail. Right now, the docs do not clearly tell users this.

2. Manage-existing rules need clearer wording

When importing an existing Alletra share into Manila, the driver expects the export path in a very specific format:

For example:

It does not accept IPv6, multiple export paths, or paths that do not start with /file/. The docs should explain this because otherwise users may not understand why manage fails.

3. Share type “case sensitive” wording is misleading

The docs say values are case sensitive, but the driver actually accepts values like true, True, or TRUE because it lowercases them internally.

Better plain wording:

“Extra spec keys must be written exactly as shown. Values such as true, false, and squash options are treated case-insensitively by the driver.”

4. Access rule behavior needs more detail

The docs say only IP-based access rules are supported, which is correct, but they should explain what that means in practice.

In simple terms:

Only IP access rules work.
User, certificate, or other access rule types do not work.
If no access rule is configured, the driver blocks access by default.
If users allow 0.0.0.0/0, the driver sends that to the backend as *, meaning all clients.
The squash option from the share type is applied to every access rule.

5. Unmanage needs one sentence of clarification

The docs say unmanage is supported but should explain what it does.

Plain version:

“Unmanage removes the share from Manila management but does not delete the share from the Alletra array.”

That distinction matters because users may expect the backend share to be removed.

6. Backend naming should be documented for troubleshooting

The driver creates backend resources using predictable names:

This is useful when an admin is looking at the Alletra array and trying to match backend objects to Manila shares.

7. Configuration table wording is slightly too broad

The docs say the table contains all supported configuration options. It really contains the main driver-specific options, not every Manila option the driver uses.

Plain fix:

“Driver-specific configuration options are listed below.”

This avoids implying that standard Manila options are not relevant.

8. HTTPS certificate behavior should be called out --- Only if you are comfortable calling it out

The driver connects to the WSAPI URL over HTTPS, but the REST client does not expose a clear configuration option for certificate verification.

Plain version:

“The driver uses HTTPS for WSAPI communication, but administrators should verify the deployment’s TLS/certificate behavior and security requirements.”

This is useful for production/security-conscious operators.

Short Summary

The docs cover the main story correctly: NFS-only, no share servers, create/delete/extend/access/manage/unmanage/ensure support, no snapshots, no replication, and the main share type options.

The missing pieces are mostly the “things that make operations fail”: exact manage path format, size limits, access-rule details and backend naming