VMware vSphere SDKs and Tools 8.0

8.0 7.0 6.7 6.5

Connect to VMware vSphere

VixDiskLib_ConnectEx()
 connects the library to managed disk on a remote ESXi host or through VMware vCenter Server. For hosted disk on the local system, it works the same as
VixDiskLib_Connect()
.
VixDiskLib_ConnectEx()
 takes three additional parameters:
  • Boolean indicating
    TRUE
     for read-only access, often faster, or
    FALSE
     for read/write access. If connecting read-only, later calls to
    VixDiskLib_Open()
     are always read-only regardless of the
    openFlags
     setting.
  • Managed object reference (
    MoRef
    ) of the snapshot to access using this connection. This is required for most transport methods (SAN, HotAdd, NBDSSL) and to access a powered-on virtual machine. You must also specify the associated
    vmxSpec
     property in
    connectParams
    . When connecting to an ESXi host, provide the ESXi
    MoRef
    . When connecting by vCenter Server, pass the vSphere
    MoRef
    , which differs.
  • Preferred transport method, or
    NULL
     to accept the defaults. If you specify any advanced transport mode as the only method, and that method is not available, the
    VixDiskLib_ConnectEx()
     call does not fail, but the subsequent
    VixDiskLib_Open()
     call will fall back to NBDSSL mode. 
    VixDiskLibConnectParams cnxParams = {0};
if (appGlobals.isRemote) {
     cnxParams.vmName = vmxSpec;
     cnxParams.serverName = hostName;
     cnxParams.credType = VIXDISKLIB_CRED_UID;
     cnxParams.creds.uid.userName = userName;
     cnxParams.creds.uid.password = password;
     cnxParams.port = port;
}
VixError vixError = VixDiskLib_ConnectEx(&cnxParams, TRUE, "snapshot-47", NULL, &connection);
When a program calls
VixDiskLib_ConnectEx()
 with NULL parameter to accept default transport mode, SAN is selected as the preferred mode, if SAN storage is available from the ESXi host. Then if the program opens a virtual disk on local storage, subsequent writes will fail. In this case, the program should explicitly pass
nbdssl
 as the preferred transport mode.
The port is where vCenter Server listens for API queries. Specifying null allows the library to select the port, usually 443 (HTTPS). By default VADP uses the same port for virtual machine operations as other SOAP-based Web Services. By default VDDK uses port 902 (VIX automation) for NBDSSL data transport.

Connect to ESXi hosts

In the connection parameters
cnxParams
, the
vmxSpec
 managed object reference would be different on an ESXi host than on the vCenter Server, as shown below. ESXi hosts offer no prepare-for and end access protection. Otherwise ESXi host connections are similar to vCenter Server connections. 
vmxSpec = "moid=23498";
vmxSpec = "moid=898273";

Reuse a vCenter Server Session

As of vSphere 6.5, you can recycle a vCenter Server session to avoid session overflow. Set the credential type to
VIXDISKLIB_CRED_SESSIONID
 and supply the value of
vmware_soap_session
 from a still-live vCenter Server session. For NBD(SSL) and HotAdd transport, the
sessionId.key
 password can be any non-empty string. For SAN transport, you must specify the actual password.
if (appGlobals.isRemote) {
     cnxParams.vmName = vmxSpec;
     cnxParams.serverName = hostName;
     cnxParams.credType = VIXDISKLIB_CRED_SESSIONID;
     cnxParams.creds.sessionId.cookie = cookie;
     cnxParams.creds.sessionId.userName = userName;
     cnxParams.creds.sessionId.key = "reuse"; /* password */
     cnxParams.port = port;
}

Content feedback and comments