gpfs:sharemodes

Read about share modes and how they impact SMB export.

The SMB protocol allows an application simultaneous access to a file by defining share modes when it is first opened. The share modes can be in any of the following combinations.

SHARE_READ
SHARE_WRITE
SHARE_DELETE

If no sharemode is specified, all attempts of simultaneous access by another application or client to open a file, in a manner that conflicts with the existing open mode, is denied. Access is denied even if the user has the appropriate permissions that are granted by share and file system access control lists.

The sharemodes option is enabled by default when an SMB export is created. When enabled, the share modes that are specified by SMB clients are respected by other NAS protocols. When disabled, it specifies that the share modes are applicable only to access by SMB clients. Clients that use all other NAS protocols are granted or denied access to a file without regard to any share mode defined by an SMB client.

If the export is not being accessed by clients that use other network file protocols (such as NFS), then it is highly recommended that

--option gpfs:sharemodes=no

option is specified on the mmsmb export add or mmsmb export change commands.

For more information, see Upgrading SMB packages.

Note: If your environment requires data sharing over multiple –protocols and these options cannot be disabled, you might not be able to achieve the maximum active SMB connections per node. In that case, consider adding more protocol nodes and increased storage bandwidth.