Name Theory_2390-1108602-44_0
Workunit 144970973
Created 12 Sep 2020, 23:02:55 UTC
Sent 13 Sep 2020, 3:16:24 UTC
Report deadline 24 Sep 2020, 3:16:24 UTC
Received 13 Sep 2020, 4:40:14 UTC
Server state Over
Outcome Computation error
Client state Compute error
Exit status 1 (0x00000001) Unknown error code
Computer ID 10658977
Run time 27 sec
CPU time
Validate state Invalid
Credit 0.00
Device peak FLOPS 4.15 GFLOPS
Application version Theory Simulation v300.06 (vbox64_theory)
windows_x86_64
Peak working set size 10.70 MB
Peak swap size 6.45 MB
Peak disk usage 781.14 MB

Stderr output

<core_client_version>7.16.7</core_client_version>
<![CDATA[
<message>
Unzul�ssige Funktion.
 (0x1) - exit code 1 (0x1)</message>
<stderr_txt>
2020-09-13 05:39:24 (17492): Detected: vboxwrapper 26197
2020-09-13 05:39:24 (17492): Detected: BOINC client v7.7
2020-09-13 05:39:27 (17492): Detected: VirtualBox VboxManage Interface (Version: 6.1.12)
2020-09-13 05:39:28 (17492): Detected: Heartbeat check (file: 'heartbeat' every 1200.000000 seconds)
2020-09-13 05:39:28 (17492): Successfully copied 'init_data.xml' to the shared directory.
2020-09-13 05:39:28 (17492): Successfully copied 'input' to the shared directory.
2020-09-13 05:39:30 (17492): Create VM. (boinc_8c53695d73f8edd5, slot#5)
2020-09-13 05:39:31 (17492): Setting Memory Size for VM. (630MB)
2020-09-13 05:39:31 (17492): Setting CPU Count for VM. (1)
2020-09-13 05:39:32 (17492): Setting Chipset Options for VM.
2020-09-13 05:39:32 (17492): Setting Boot Options for VM.
2020-09-13 05:39:33 (17492): Setting Network Configuration for NAT.
2020-09-13 05:39:33 (17492): Enabling VM Network Access.
2020-09-13 05:39:34 (17492): Disabling USB Support for VM.
2020-09-13 05:39:34 (17492): Disabling COM Port Support for VM.
2020-09-13 05:39:34 (17492): Disabling LPT Port Support for VM.
2020-09-13 05:39:35 (17492): Disabling Audio Support for VM.
2020-09-13 05:39:36 (17492): Disabling Clipboard Support for VM.
2020-09-13 05:39:36 (17492): Disabling Drag and Drop Support for VM.
2020-09-13 05:39:37 (17492): Adding storage controller(s) to VM.
2020-09-13 05:39:37 (17492): Adding virtual disk drive to VM. (vm_image.vdi)
2020-09-13 05:39:38 (17492): Adding VirtualBox Guest Additions to VM.
2020-09-13 05:39:38 (17492): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2020-09-13 05:39:38 (17492): forwarding host port 65078 to guest port 80
2020-09-13 05:39:38 (17492): Enabling remote desktop for VM.
2020-09-13 05:39:39 (17492): Required extension pack not installed, remote desktop not enabled.
2020-09-13 05:39:39 (17492): Enabling shared directory for VM.
2020-09-13 05:39:40 (17492): Starting VM using VBoxManage interface. (boinc_8c53695d73f8edd5, slot#5)
2020-09-13 05:39:41 (17492): Error in start VM for VM: 1
Command:
VBoxManage -q startvm "boinc_8c53695d73f8edd5" --type headless
Output:
Waiting for VM "boinc_8c53695d73f8edd5" to power on...
VBoxManage.exe: error: The virtual machine 'boinc_8c53695d73f8edd5' has terminated unexpectedly during startup with exit code 1 (0x1).  More details may be available in 'C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\Logs\VBoxHardening.log'
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component MachineWrap, interface IMachine

2020-09-13 05:39:41 (17492): VM failed to start.
2020-09-13 05:39:41 (17492): Could not start 
2020-09-13 05:39:41 (17492): ERROR: VM failed to start
2020-09-13 05:39:41 (17492): Powering off VM.
2020-09-13 05:39:41 (17492): Deregistering VM. (boinc_8c53695d73f8edd5, slot#5)
2020-09-13 05:39:42 (17492): Removing network bandwidth throttle group from VM.
2020-09-13 05:39:42 (17492): Removing VM from VirtualBox.

    Hypervisor System Log:

00:00:00.489275 main     Firmware type: BIOS
00:00:00.489285 main     Host RAM: 16136MB (15.7GB) total, 6971MB (6.8GB) available
00:00:00.489291 main     Executable: C:\Program Files\Oracle\VirtualBox\VBoxSVC.exe
00:00:00.489292 main     Process ID: 29848
00:00:00.489292 main     Package type: WINDOWS_64BITS_GENERIC
00:00:00.635181          VirtualBox: object creation starts
00:00:00.636743          Home directory: 'C:\Users\admin\.VirtualBox'
00:00:00.636915          Installed Drivers:
00:00:00.645995            C:\WINDOWS\system32\DRIVERS\VBoxNetLwf.sys (Version: 6.1.12.39181)
00:00:00.649126            C:\WINDOWS\system32\DRIVERS\VBoxNetAdp6.sys (Version: 6.1.12.39181)
00:00:00.656920          Loading settings file "C:\Users\admin\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:00.658176          USBLibInit: USB Service not found
00:00:01.041555          HostDnsMonitor: initializing
00:00:01.076235          HostDnsMonitor: updating information
00:00:01.076272          HostDnsMonitor: old information
00:00:01.076274            no server entries
00:00:01.076275            no domain set
00:00:01.076276            no search string entries
00:00:01.076276          HostDnsMonitor: new information
00:00:01.076277            server 1: 192.168.178.1
00:00:01.076278            domain: fritz.box
00:00:01.076279            no search string entries
00:00:01.327367          VD: VDInit finished with VINF_SUCCESS
00:00:01.330656          VirtualBox: object created
00:00:02.530302          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={d0a0163f-e254-4e5b-a1f2-011cf991c38d} aComponent={VirtualBoxWrap} aText={Could not find a registered machine named 'boinc_8c53695d73f8edd5'}, preserve=false aResultDetail=0
00:00:03.830423          Saving settings file "C:\Users\admin\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:04.570925          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:04.582039          Saving settings file "C:\Users\admin\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:04.876499          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:05.762214          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:06.107163          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:06.433246          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:07.436791          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:07.807967          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:08.071779          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:08.339763          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:08.615225          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:09.044889          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:09.986009          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:10.853468          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:11.127938          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:11.580378          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:11.927649          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={85632c68-b5bb-4316-a900-5eb28d3413df} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 0 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:11.941795          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={85632c68-b5bb-4316-a900-5eb28d3413df} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 0 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:11.942197          Saving settings file "C:\Users\admin\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:11.954415          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:12.318621          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={85632c68-b5bb-4316-a900-5eb28d3413df} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 1 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:12.340259          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={85632c68-b5bb-4316-a900-5eb28d3413df} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 1 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:12.340514          Saving settings file "C:\Users\admin\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:12.353296          Saving settings file "C:\Users\admin\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:12.365983          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:12.630330          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:12.879193          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:13.425063          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:14.369442          Launched VM: 66265456 pid: 13136 (0x3350) frontend: headless name: boinc_8c53695d73f8edd5
00:00:15.410880 Watcher  ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={85632c68-b5bb-4316-a900-5eb28d3413df} aComponent={MachineWrap} aText={The virtual machine 'boinc_8c53695d73f8edd5' has terminated unexpectedly during startup with exit code 1 (0x1).  More details may be available in 'C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\Logs\VBoxHardening.log'}, preserve=false aResultDetail=0
00:00:15.411916 Watcher  Reaper: Pid 13136 (3350) exited normally: 1 (0x1)
00:00:15.918635          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={85632c68-b5bb-4316-a900-5eb28d3413df} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:16.505752          Saving settings file "C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox" with version "1.16-windows"
00:00:17.219100          Saving settings file "C:\Users\admin\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:22.499220 main     VirtualBox: object deletion starts
00:00:22.500131 main     HostDnsMonitor: shutting down ...
00:00:22.500190 main     HostDnsMonitor: shut down
00:00:22.501336 Watcher  ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={d0a0163f-e254-4e5b-a1f2-011cf991c38d} aComponent={VirtualBoxWrap} aText={The object is not ready}, preserve=false aResultDetail=0
00:00:22.501547 main     VirtualBox: object deleted

    VM Execution Log:


    VM Startup Log:


    VM Trace Log:

virtualization use: off
Default hard disk format:        VDI
VRDE auth library:               VBoxAuth
Webservice auth. library:        VBoxAuth
Remote desktop ExtPack:          
Log history count:               3
Default frontend:                
Default audio driver:            DirectSound
Autostart database path:         
Default Guest Additions ISO:     C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso
Logging Level:                   all
Proxy Mode:                      System
Proxy URL:                       

2020-09-13 05:39:27 (17492): 
Command: VBoxManage -q list hostinfo 
Exit Code: 0
Output:
Host Information:

Host time: 2020-09-13T03:39:27.859000000Z
Processor online count: 8
Processor count: 8
Processor online core count: 4
Processor core count: 4
Processor supports HW virtualization: yes
Processor supports PAE: yes
Processor supports long mode: yes
Processor supports nested paging: no
Processor supports unrestricted guest: no
Processor supports nested HW virtualization: no
Processor#0 speed: unknown
Processor#0 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Processor#1 speed: unknown
Processor#1 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Processor#2 speed: unknown
Processor#2 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Processor#3 speed: unknown
Processor#3 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Processor#4 speed: unknown
Processor#4 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Processor#5 speed: unknown
Processor#5 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Processor#6 speed: unknown
Processor#6 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Processor#7 speed: unknown
Processor#7 description: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Memory size: 16136 MByte
Memory available: 7118 MByte
Operating system: Windows 10
Operating system version: 10.0.18363

2020-09-13 05:39:28 (17492): 
Command: VBoxManage -q showvminfo "boinc_8c53695d73f8edd5" --machinereadable 
Exit Code: -2135228415
Output:
VBoxManage.exe: error: Could not find a registered machine named 'boinc_8c53695d73f8edd5'
VBoxManage.exe: error: Details: code VBOX_E_OBJECT_NOT_FOUND (0x80bb0001), component VirtualBoxWrap, interface IVirtualBox, callee IUnknown
VBoxManage.exe: error: Context: "FindMachine(Bstr(VMNameOrUuid).raw(), machine.asOutParam())" at line 2715 of file VBoxManageInfo.cpp

2020-09-13 05:39:29 (17492): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC\slots\5/vm_image.vdi" 
Exit Code: 0
Output:
UUID:           c7cbbeeb-c984-467e-9b6e-0d2e670bed58
Parent UUID:    base
State:          created
Type:           normal (base)
Location:       C:\ProgramData\BOINC\slots\5\vm_image.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       20480 MBytes
Size on disk:   781 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2020-09-13 05:39:29 (17492): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC\slots\5/vm_image.vdi" 
Exit Code: 0
Output:
UUID:           c7cbbeeb-c984-467e-9b6e-0d2e670bed58
Parent UUID:    base
State:          created
Type:           normal (base)
Location:       C:\ProgramData\BOINC\slots\5\vm_image.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       20480 MBytes
Size on disk:   781 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2020-09-13 05:39:30 (17492): 
Command: VBoxManage -q closemedium disk "C:\ProgramData\BOINC\slots\5/vm_image.vdi" 
Exit Code: 0
Output:

2020-09-13 05:39:30 (17492): 
Command: VBoxManage -q createvm --name "boinc_8c53695d73f8edd5" --basefolder "C:\ProgramData\BOINC\slots\5" --ostype "Linux26_64" --register
Exit Code: 0
Output:
Virtual machine 'boinc_8c53695d73f8edd5' is created and registered.
UUID: e8517514-dbad-4cb5-8080-896ef8cf02d5
Settings file: 'C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\boinc_8c53695d73f8edd5.vbox'

2020-09-13 05:39:31 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --description "Theory_2390-1108602-44_0" 
Exit Code: 0
Output:

2020-09-13 05:39:31 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --memory 630 
Exit Code: 0
Output:

2020-09-13 05:39:32 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --cpus 1 
Exit Code: 0
Output:

2020-09-13 05:39:32 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --acpi on --ioapic on 
Exit Code: 0
Output:

2020-09-13 05:39:33 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --boot1 disk --boot2 dvd --boot3 none --boot4 none 
Exit Code: 0
Output:

2020-09-13 05:39:33 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --nic1 nat --natdnsproxy1 on --cableconnected1 off 
Exit Code: 0
Output:

2020-09-13 05:39:34 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --cableconnected1 on 
Exit Code: 0
Output:

2020-09-13 05:39:34 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --usb off 
Exit Code: 0
Output:

2020-09-13 05:39:34 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --uart1 off --uart2 off 
Exit Code: 0
Output:

2020-09-13 05:39:35 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --lpt1 off --lpt2 off 
Exit Code: 0
Output:

2020-09-13 05:39:36 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --audio none 
Exit Code: 0
Output:

2020-09-13 05:39:36 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --clipboard disabled 
Exit Code: 0
Output:

2020-09-13 05:39:37 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --draganddrop disabled 
Exit Code: 0
Output:

2020-09-13 05:39:37 (17492): 
Command: VBoxManage -q storagectl "boinc_8c53695d73f8edd5" --name "Hard Disk Controller" --add "ide" --controller "PIIX4" 
Exit Code: 0
Output:

2020-09-13 05:39:38 (17492): 
Command: VBoxManage -q storageattach "boinc_8c53695d73f8edd5" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --setuuid "" --medium "C:\ProgramData\BOINC\slots\5/vm_image.vdi" 
Exit Code: 0
Output:

2020-09-13 05:39:38 (17492): 
Command: VBoxManage -q storageattach "boinc_8c53695d73f8edd5" --storagectl "Hard Disk Controller" --port 1 --device 0 --type dvddrive --medium "C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso" 
Exit Code: 0
Output:

2020-09-13 05:39:38 (17492): 
Command: VBoxManage -q bandwidthctl "boinc_8c53695d73f8edd5" add "boinc_8c53695d73f8edd5_net" --type network --limit 1024G 
Exit Code: 0
Output:

2020-09-13 05:39:38 (17492): 
Command: VBoxManage -q modifyvm "boinc_8c53695d73f8edd5" --natpf1 ",tcp,127.0.0.1,65078,,80" 
Exit Code: 0
Output:

2020-09-13 05:39:39 (17492): 
Command: VBoxManage -q list extpacks
Exit Code: 0
Output:
Extension Packs: 0

2020-09-13 05:39:40 (17492): 
Command: VBoxManage -q sharedfolder add "boinc_8c53695d73f8edd5" --name "shared" --hostpath "C:\ProgramData\BOINC\slots\5/shared"
Exit Code: 0
Output:

2020-09-13 05:39:41 (17492): 
Command: VBoxManage -q startvm "boinc_8c53695d73f8edd5" --type headless
Exit Code: 1
Output:
Waiting for VM "boinc_8c53695d73f8edd5" to power on...
VBoxManage.exe: error: The virtual machine 'boinc_8c53695d73f8edd5' has terminated unexpectedly during startup with exit code 1 (0x1).  More details may be available in 'C:\ProgramData\BOINC\slots\5\boinc_8c53695d73f8edd5\Logs\VBoxHardening.log'
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component MachineWrap, interface IMachine

2020-09-13 05:39:41 (17492): 
Command: VBoxManage -q snapshot "boinc_8c53695d73f8edd5" list 
Exit Code: -108
Output:
This machine does not have any snapshots

2020-09-13 05:39:42 (17492): 
Command: VBoxManage -q bandwidthctl "boinc_8c53695d73f8edd5" remove "boinc_8c53695d73f8edd5_net" 
Exit Code: 0
Output:

2020-09-13 05:39:43 (17492): 
Command: VBoxManage -q unregistervm "boinc_8c53695d73f8edd5" --delete 
Exit Code: 0
Output:
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

05:39:48 (17492): called boinc_finish(1)

</stderr_txt>
]]>


©2025 CERN