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Virtual Disk Development Kit library reports the error: Failed to open NBD extent, NBD_ERR_GENERIC (1022543)
- You cannot open <VM Name>.vmdk files
- You see the error:
Failed to open NBD extent, NBD_ERR_GENERIC
- Virtual Disk Development Kit (VDDK) logs found in Server 2003: C:\Documents and Settings\<username>\Local Settings\Temp\vmware-<username>\, Server 2008: C:\Users\<username>\AppData\Local\Temp\2\vmware-<username>, Linux: /tmp/vmware-root/ report errors similar to:
[NFC ERROR] NfcFssrvrRecv: failed with code = 8
[NFC ERROR] NfcFssrvr_DiskOpen: failed to receive open reply
[NFC ERROR] NfcNetTcpWrite: bWritten: -1
[NFC ERROR] NfcNet_Send: requested 264, sent only -1 bytes
[NFC ERROR] NfcSendMessage: send failed
- The vpxa.log file located at /var/log/vmware/vpx on ESX/ESXi 4.x hosts reports errors similar to:
F5AC8B90 info 'Libs'] NfcNetTcpRead: timed out waiting for data
F5AC8B90 warning 'Libs'] [NFC ERROR] NfcFssrvrRecv: failed with code = 9
- The vpxa.log file located at /var/log/ on ESXi 5.x hosts reports errors similar to:
[NFC ERROR] NfcCheckAndReserveMem: Cannot allocate any more memory as NFC is already using 31457329 and allocating 2097152 will make it more than the maximum allocated: 33554432. Please close some sessions and try again
To resolve this issue:
- Ensure that the unused NFC connections are closed properly.
- Limit concurrent
scheduled backups per ESX\ESXi host or vCenter Server.
- VixDiskLib_Open() uses one connection for every virtual disk that it accesses on an ESX/ESXi host.
- VixDiskLib_Clone() also requires a connection.
is not possible to share a connection across disks.
- The ESX\ESXi limits depend on consumed buffer space, not the number of connections.
For more information on the number of concurrent NFC connections, see Virtual Disk Transport Methods.
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