Since upgrading to Plug-in for VMware 11.3, Advanced Transport Modes such as SAN and Hotadd cannot be used during backups and the standard transport mode NBD is used instead.
VDDK vixDiskLib*.logs show we cannot load the disklibPlugin.dll therefore any advanced transport mode cannot be used and we fallback to NBD:
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2017-03-23T10:14:50.256+01:00| vthread-4| I125: VixDiskLib: Attempting to locate advanced transport module in "E:/NetVault Backup/bin/vmware".
2017-03-23T10:14:50.257+01:00| vthread-4| I125: VixDiskLib: Could not load default plugins from E:/NetVault Backup/bin/vmware\bin\disklibplugin.dll: Cannot open library: Unknown error 126 (0x7e).
2017-03-23T10:14:50.257+01:00| vthread-4| I130: VixDiskLib: Available transport modes from DiskLib: file:nbdssl:nbd.
2017-03-23T10:14:50.257+01:00| vthread-4| I125: VixDiskLib: Advanced transport module not loaded.
2017-03-23T10:14:50.257+01:00| vthread-4| I125: VixDiskLib: Using transport modes from DiskLib: file:nbdssl:nbd.
2017-03-23T10:15:40.164+01:00| vthread-4| I125: VixDiskLib: VixDiskLib_GetTransportMode: Retrieve transport mode.
2017-03-23T10:15:41.013+01:00| vthread-4| I125: VixDiskLib: VixDiskLib_ConnectEx: Establish connection using san:nbd.
2017-03-23T10:15:41.013+01:00| vthread-4| I125: VixDiskLib: VixDiskLib_ConnectEx: No transport plugin. Advanced transports not available.
2017-03-23T10:15:41.013+01:00| vthread-4| I130: VixDiskLib: Open a disk with standard transport mode.
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In some cases, because NBD is used with default 65536 Read Block size, many backups will start to fail due to memory allocation problems when there are large backups with multiple VMs and parallel streams.
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[NFC ERROR] NfcFssrvrProcessErrorMsg: received NFC error 5 from server: Failed to allocate the requested 33554456 bytes
2017-03-23T10:15:44.113+01:00| vthread-4| E110: VixDiskLib: Detected DiskLib error 802 (NBD_ERR_INSUFFICIENT_RESOURCES).
2017-03-23T10:15:44.113+01:00| vthread-4| E110: VixDiskLib: VixDiskLib_Read: Read 65536 sectors at 284672 failed. Error 2 (Memory allocation failed. Out of memory.) (DiskLib error 802: NBD_ERR_INSUFFICIENT_RESOURCES) at 5178.
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