| Name | CMS_1602798_1727656478.149908_0 |
| Workunit | 225732734 |
| Created | 30 Sep 2024, 0:34:42 UTC |
| Sent | 30 Sep 2024, 2:07:28 UTC |
| Report deadline | 31 Oct 2024, 2:07:28 UTC |
| Received | 30 Sep 2024, 2:20:13 UTC |
| Server state | Over |
| Outcome | Computation error |
| Client state | Compute error |
| Exit status | -2147467259 (0x80004005) Unknown error code |
| Computer ID | 10773470 |
| Run time | 21 sec |
| CPU time | 0 sec |
| Validate state | Invalid |
| Credit | 0.00 |
| Device peak FLOPS | 24.22 GFLOPS |
| Application version | CMS Simulation v70.30 (vbox64_mt_mcore_cms) windows_x86_64 |
| Peak working set size | 12.51 MB |
| Peak swap size | 7.78 MB |
| Peak disk usage | 9.16 KB |
Stderr output
<core_client_version>8.0.4</core_client_version>
<![CDATA[
<message>
Unspecified error
(0x80004005) - exit code 2147500037 (0x80004005)</message>
<stderr_txt>
2024-09-29 21:11:05 (14088): vboxwrapper version 26207
2024-09-29 21:11:05 (14088): BOINC client version: 8.0.4
2024-09-29 21:11:07 (14088): Detected: VirtualBox VboxManage Interface (Version: 7.0.20)
2024-09-29 21:11:07 (14088): Detected: Heartbeat check (file: 'heartbeat' every 1200.000000 seconds)
2024-09-29 21:11:07 (14088): Successfully copied 'init_data.xml' to the shared directory.
2024-09-29 21:11:07 (14088): Create VM. (boinc_555add9aa631282c, slot#2)
2024-09-29 21:11:08 (14088): Setting Memory Size for VM. (4584MB)
2024-09-29 21:11:08 (14088): Setting CPU Count for VM. (4)
2024-09-29 21:11:08 (14088): Setting Chipset Options for VM.
2024-09-29 21:11:09 (14088): Setting Graphics Controller Options for VM.
2024-09-29 21:11:09 (14088): Setting Boot Options for VM.
2024-09-29 21:11:09 (14088): Setting Network Configuration for NAT.
2024-09-29 21:11:10 (14088): Enabling VM Network Access.
2024-09-29 21:11:10 (14088): Disabling USB Support for VM.
2024-09-29 21:11:10 (14088): Disabling COM Port Support for VM.
2024-09-29 21:11:10 (14088): Disabling LPT Port Support for VM.
2024-09-29 21:11:11 (14088): Disabling Audio Support for VM.
2024-09-29 21:11:11 (14088): Disabling Clipboard Support for VM.
2024-09-29 21:11:11 (14088): Disabling Drag and Drop Support for VM.
2024-09-29 21:11:11 (14088): Adding storage controller(s) to VM.
2024-09-29 21:11:12 (14088): Adding virtual disk drive to VM. (CMS_2024_04_29_prod.vdi)
2024-09-29 21:11:14 (14088): Adding VirtualBox Guest Additions to VM.
2024-09-29 21:11:14 (14088): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2024-09-29 21:11:15 (14088): forwarding host port 65043 to guest port 80
2024-09-29 21:11:15 (14088): Enabling remote desktop for VM.
2024-09-29 21:11:15 (14088): Required extension pack not installed, remote desktop not enabled.
2024-09-29 21:11:15 (14088): Enabling shared directory for VM.
2024-09-29 21:11:16 (14088): Starting VM using VBoxManage interface. (boinc_555add9aa631282c, slot#2)
2024-09-29 21:11:19 (14088): Error in start VM for VM: -2147467259
Command:
VBoxManage -q startvm "boinc_555add9aa631282c" --type headless
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: AMD-V is disabled in the BIOS (or by the host OS) (VERR_SVM_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_555add9aa631282c" to power on...
2024-09-29 21:11:19 (14088): VM failed to start.
2024-09-29 21:11:19 (14088): Could not start
2024-09-29 21:11:19 (14088): ERROR: VM failed to start
2024-09-29 21:11:19 (14088): Powering off VM.
2024-09-29 21:11:19 (14088): Deregistering VM. (boinc_555add9aa631282c, slot#2)
2024-09-29 21:11:19 (14088): Removing network bandwidth throttle group from VM.
2024-09-29 21:11:20 (14088): Removing VM from VirtualBox.
Hypervisor System Log:
00:00:08.072145 Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox" with version "1.19-windows"
00:00:08.076501 Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox"
00:00:08.306792 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.306840 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.313790 Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox" with version "1.19-windows"
00:00:08.318925 Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox"
00:00:08.581378 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.581424 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.588384 Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox" with version "1.19-windows"
00:00:08.592453 Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox"
00:00:09.141415 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.141467 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.147558 Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox" with version "1.19-windows"
00:00:09.153640 Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox"
00:00:09.414601 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.414651 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.419574 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={7682d5eb-f00e-44f1-8ca2-99d08b1cd607} aComponent={VirtualBoxWrap} aText={Ńo extension pack providing a cryptographic support module could be found}, preserve=false aResultDetail=0
00:00:09.430730 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:09.430854 ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:09.441984 ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:09.681141 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.681189 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.695315 Launched VM: 4050226144 pid: 4892 (0x131c) frontend: headless name: boinc_555add9aa631282c
00:00:13.258702 Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox" with version "1.19-windows"
00:00:13.263557 Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox"
00:00:13.361217 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.361251 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.364225 ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:13.448972 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.449016 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.455439 Saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox" with version "1.19-windows"
00:00:13.460373 Finished saving settings file "C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox"
00:00:13.720540 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.720588 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.721569 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.721607 ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:13.722487 Saving settings file "C:\Users\Lothar\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:13.734607 Finished saving settings file "C:\Users\Lothar\.VirtualBox\VirtualBox.xml"
00:00:13.735402 Saving settings file "C:\Users\Lothar\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:13.744378 Finished saving settings file "C:\Users\Lothar\.VirtualBox\VirtualBox.xml"
00:00:13.746027 DeleteVM Saving settings file "C:\Users\Lothar\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:13.755827 DeleteVM Finished saving settings file "C:\Users\Lothar\.VirtualBox\VirtualBox.xml"
00:00:18.777792 main VirtualBox: object deletion starts
00:00:18.787092 main HostDnsMonitor: shutting down ...
00:00:18.787132 main HostDnsMonitor: shut down
00:00:18.791737 Watcher ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={7682d5eb-f00e-44f1-8ca2-99d08b1cd607} aComponent={VirtualBoxWrap} aText={The object is not ready}, preserve=false aResultDetail=0
00:00:18.792355 main VirtualBox: object deleted
VM Execution Log:
VM Startup Log:
VM Trace Log:
(VMNameOrUuid).raw(), machine.asOutParam())" at line 3139 of file VBoxManageInfo.cpp
2024-09-29 21:11:08 (14088):
Command: VBoxManage -q createvm --name "boinc_555add9aa631282c" --basefolder "C:\ProgramData\BOINC\slots\2" --ostype "Linux26_64" --register
Exit Code: 0
Output:
Virtual machine 'boinc_555add9aa631282c' is created and registered.
UUID: 41fa12c4-e8af-4a16-96b7-3343915ed25a
Settings file: 'C:\ProgramData\BOINC\slots\2\boinc_555add9aa631282c\boinc_555add9aa631282c.vbox'
2024-09-29 21:11:08 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --description "CMS_1602798_1727656478.149908_0"
Exit Code: 0
Output:
2024-09-29 21:11:08 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --memory 4584
Exit Code: 0
Output:
2024-09-29 21:11:08 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --cpus 4
Exit Code: 0
Output:
2024-09-29 21:11:09 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --acpi on --ioapic on --rtcuseutc off
Exit Code: 0
Output:
2024-09-29 21:11:09 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --vram 16 --graphicscontroller VBoxVGA
Exit Code: 0
Output:
2024-09-29 21:11:09 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --boot1 disk --boot2 dvd --boot3 none --boot4 none
Exit Code: 0
Output:
2024-09-29 21:11:10 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --nic1 nat --natdnsproxy1 on --cableconnected1 off
Exit Code: 0
Output:
2024-09-29 21:11:10 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --cableconnected1 on
Exit Code: 0
Output:
2024-09-29 21:11:10 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --usb off
Exit Code: 0
Output:
2024-09-29 21:11:10 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --uart1 off --uart2 off
Exit Code: 0
Output:
2024-09-29 21:11:11 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --lpt1 off --lpt2 off
Exit Code: 0
Output:
2024-09-29 21:11:11 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --audio-enabled off
Exit Code: 0
Output:
2024-09-29 21:11:11 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --clipboard disabled
Exit Code: 0
Output:
2024-09-29 21:11:11 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --draganddrop disabled
Exit Code: 0
Output:
2024-09-29 21:11:12 (14088):
Command: VBoxManage -q storagectl "boinc_555add9aa631282c" --name "Hard Disk Controller" --add "sata" --controller "IntelAHCI" --hostiocache off --portcount 3
Exit Code: 0
Output:
2024-09-29 21:11:12 (14088):
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/CMS_2024_04_29_prod.vdi"
Exit Code: 0
Output:
UUID: 461abfaf-39ef-4b91-89ba-53cae0787c5e
Parent UUID: base
State: created
Type: multiattach
Location: C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\CMS_2024_04_29_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity: 20480 MBytes
Size on disk: 3853 MBytes
Encryption: disabled
Property: AllocationBlockSize=1048576
2024-09-29 21:11:12 (14088):
Command: VBoxManage -q storageattach "boinc_555add9aa631282c" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/CMS_2024_04_29_prod.vdi"
Exit Code: -2135228409
Output:
VBoxManage.exe: error: Cannot attach medium 'C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\CMS_2024_04_29_prod.vdi': the media type 'MultiAttach' can only be attached to machines that were created with VirtualBox 4.0 or later
VBoxManage.exe: error: Details: code VBOX_E_INVALID_OBJECT_STATE (0x80bb0007), component SessionMachine, interface IMachine, callee IUnknown
VBoxManage.exe: error: Context: "AttachDevice(Bstr(pszCtl).raw(), port, device, DeviceType_HardDisk, pMedium2Mount)" at line 785 of file VBoxManageStorageController.cpp
2024-09-29 21:11:13 (14088):
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/CMS_2024_04_29_prod.vdi"
Exit Code: 0
Output:
UUID: 461abfaf-39ef-4b91-89ba-53cae0787c5e
Parent UUID: base
State: created
Type: multiattach
Location: C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\CMS_2024_04_29_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity: 20480 MBytes
Size on disk: 3853 MBytes
Encryption: disabled
Property: AllocationBlockSize=1048576
2024-09-29 21:11:13 (14088):
Command: VBoxManage -q closemedium disk "C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\CMS_2024_04_29_prod.vdi"
Exit Code: 0
Output:
2024-09-29 21:11:13 (14088):
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/CMS_2024_04_29_prod.vdi"
Exit Code: 0
Output:
UUID: 461abfaf-39ef-4b91-89ba-53cae0787c5e
Parent UUID: base
State: created
Type: normal (base)
Location: C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\CMS_2024_04_29_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity: 20480 MBytes
Size on disk: 3853 MBytes
Encryption: disabled
Property: AllocationBlockSize=1048576
2024-09-29 21:11:13 (14088):
Command: VBoxManage -q storageattach "boinc_555add9aa631282c" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/CMS_2024_04_29_prod.vdi"
Exit Code: 0
Output:
2024-09-29 21:11:14 (14088):
Command: VBoxManage -q storageattach "boinc_555add9aa631282c" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium none
Exit Code: 0
Output:
2024-09-29 21:11:14 (14088):
Command: VBoxManage -q storageattach "boinc_555add9aa631282c" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/CMS_2024_04_29_prod.vdi"
Exit Code: 0
Output:
2024-09-29 21:11:14 (14088):
Command: VBoxManage -q storageattach "boinc_555add9aa631282c" --storagectl "Hard Disk Controller" --port 1 --device 0 --type dvddrive --medium "C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso"
Exit Code: 0
Output:
2024-09-29 21:11:15 (14088):
Command: VBoxManage -q bandwidthctl "boinc_555add9aa631282c" add "boinc_555add9aa631282c_net" --type network --limit 1024G
Exit Code: 0
Output:
2024-09-29 21:11:15 (14088):
Command: VBoxManage -q modifyvm "boinc_555add9aa631282c" --natpf1 ",tcp,127.0.0.1,65043,,80"
Exit Code: 0
Output:
2024-09-29 21:11:15 (14088):
Command: VBoxManage -q list extpacks
Exit Code: 0
Output:
Extension Packs: 0
2024-09-29 21:11:15 (14088):
Command: VBoxManage -q sharedfolder add "boinc_555add9aa631282c" --name "shared" --hostpath "C:\ProgramData\BOINC\slots\2/shared"
Exit Code: 0
Output:
2024-09-29 21:11:19 (14088):
Command: VBoxManage -q startvm "boinc_555add9aa631282c" --type headless
Exit Code: -2147467259
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: AMD-V is disabled in the BIOS (or by the host OS) (VERR_SVM_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_555add9aa631282c" to power on...
2024-09-29 21:11:19 (14088):
Command: VBoxManage -q snapshot "boinc_555add9aa631282c" list
Exit Code: -108
Output:
This machine does not have any snapshots
2024-09-29 21:11:20 (14088):
Command: VBoxManage -q bandwidthctl "boinc_555add9aa631282c" remove "boinc_555add9aa631282c_net"
Exit Code: 0
Output:
2024-09-29 21:11:20 (14088):
Command: VBoxManage -q unregistervm "boinc_555add9aa631282c" --delete
Exit Code: 0
Output:
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
2024-09-29 21:11:25 (14088): called boinc_finish(-2147467259)
</stderr_txt>
]]>
©2024 CERN