Name Theory_2773-2967445-185_2
Workunit 229775757
Created 20 Jan 2025, 21:05:17 UTC
Sent 21 Jan 2025, 3:16:25 UTC
Report deadline 1 Feb 2025, 3:16:25 UTC
Received 22 Jan 2025, 4:16:54 UTC
Server state Over
Outcome Computation error
Client state Compute error
Exit status -2147467259 (0x80004005) Unknown error code
Computer ID 10857369
Run time 26 sec
CPU time
Validate state Invalid
Credit 0.00
Device peak FLOPS 6.13 GFLOPS
Application version Theory Simulation v300.60 (vbox64_theory)
windows_x86_64
Peak working set size 7.59 MB
Peak swap size 1.91 MB
Peak disk usage 0.87 MB

Stderr output

<core_client_version>8.0.2</core_client_version>
<![CDATA[
<message>
Unspecified error
 (0x80004005) - exit code 2147500037 (0x80004005)</message>
<stderr_txt>
2025-01-21 22:54:02 (19104): vboxwrapper version 26208
2025-01-21 22:54:02 (19104): BOINC client version: 8.0.2
2025-01-21 22:54:04 (19104): Detected: VirtualBox VboxManage Interface (Version: 7.1.4)
2025-01-21 22:54:04 (19104): Detected: Heartbeat check (file: 'heartbeat' every 1200.000000 seconds)
2025-01-21 22:54:04 (19104): Successfully copied 'init_data.xml' to the shared directory.
2025-01-21 22:54:04 (19104): Successfully copied 'input' to the shared directory.
2025-01-21 22:54:04 (19104): Create VM. (boinc_66f3979161914023, slot#15)
2025-01-21 22:54:05 (19104): Setting Memory Size for VM. (630MB)
2025-01-21 22:54:05 (19104): Setting CPU Count for VM. (1)
2025-01-21 22:54:05 (19104): Setting Chipset Options for VM.
2025-01-21 22:54:06 (19104): Setting Graphics Controller Options for VM.
2025-01-21 22:54:06 (19104): Setting Boot Options for VM.
2025-01-21 22:54:06 (19104): Setting Network Configuration for NAT.
2025-01-21 22:54:07 (19104): Enabling VM Network Access.
2025-01-21 22:54:07 (19104): Disabling USB Support for VM.
2025-01-21 22:54:07 (19104): Disabling COM Port Support for VM.
2025-01-21 22:54:07 (19104): Disabling LPT Port Support for VM.
2025-01-21 22:54:08 (19104): Disabling Audio Support for VM.
2025-01-21 22:54:08 (19104): Disabling Clipboard Support for VM.
2025-01-21 22:54:08 (19104): Disabling Drag and Drop Support for VM.
2025-01-21 22:54:09 (19104): Adding storage controller(s) to VM.
2025-01-21 22:54:09 (19104): Adding virtual disk drive to VM. (Theory_2025_01_16_prod.vdi)
2025-01-21 22:54:14 (19104): Attempts: 3
2025-01-21 22:54:15 (19104): Adding VirtualBox Guest Additions to VM.
2025-01-21 22:54:15 (19104): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2025-01-21 22:54:15 (19104): forwarding host port 56398 to guest port 80
2025-01-21 22:54:15 (19104): Enabling remote desktop for VM.
2025-01-21 22:54:16 (19104): Enabling shared directory for VM.
2025-01-21 22:54:17 (19104): Starting VM using VBoxManage interface. (boinc_66f3979161914023, slot#15)
2025-01-21 22:54:21 (19104): Error in start VM for VM: -2147467259
Command:
VBoxManage -q startvm "boinc_66f3979161914023" --type headless
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_66f3979161914023" to power on...

2025-01-21 22:54:21 (19104): VM failed to start.
2025-01-21 22:54:21 (19104): Could not start 
2025-01-21 22:54:21 (19104): ERROR: VM failed to start
2025-01-21 22:54:21 (19104): Powering off VM.
2025-01-21 22:54:21 (19104): Deregistering VM. (boinc_66f3979161914023, slot#15)
2025-01-21 22:54:21 (19104): Removing network bandwidth throttle group from VM.
2025-01-21 22:54:21 (19104): Removing VM from VirtualBox.

    Hypervisor System Log:

00:00:13.745881          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:13.745990          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:13.930822          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={bea3ef5c-de2f-4b74-aa3a-15d6249371a0} aComponent={RecordingSettingsWrap} aText={Recording not started}, preserve=false aResultDetail=0
00:00:13.931606          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:14.054594          Platform architecture set to 'x86'
00:00:14.231324          Launched VM: 3320006464 pid: 5900 (0x170c) frontend: headless name: boinc_66f3979161914023
00:00:14.850311          Saving settings file "D:\slots\16\boinc_f21efd0138d71d23\boinc_f21efd0138d71d23.vbox" with version "1.19-windows"
00:00:14.853726          Finished saving settings file "D:\slots\16\boinc_f21efd0138d71d23\boinc_f21efd0138d71d23.vbox"
00:00:14.858952          Platform architecture set to 'x86'
00:00:15.095598          Platform architecture set to 'x86'
00:00:15.096739          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:15.171436          Platform architecture set to 'x86'
00:00:15.173267          Saving settings file "D:\slots\16\boinc_f21efd0138d71d23\boinc_f21efd0138d71d23.vbox" with version "1.19-windows"
00:00:15.175876          Finished saving settings file "D:\slots\16\boinc_f21efd0138d71d23\boinc_f21efd0138d71d23.vbox"
00:00:15.431040          Saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:15.433269          Finished saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml"
00:00:15.433471          Saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox" with version "1.19-windows"
00:00:15.436099          Finished saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox"
00:00:15.437117 DeleteVM Saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox" with version "1.19-windows"
00:00:15.439633 DeleteVM Finished saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox"
00:00:15.758541          Saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox" with version "1.19-windows"
00:00:15.761244          Finished saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox"
00:00:15.862114          Platform architecture set to 'x86'
00:00:15.863679          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:15.933837          Platform architecture set to 'x86'
00:00:15.935280          Saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox" with version "1.19-windows"
00:00:15.937675          Finished saving settings file "D:\slots\8\boinc_4d29f01d1f26be27\boinc_4d29f01d1f26be27.vbox"
00:00:16.196987          Saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:16.199155          Finished saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml"
00:00:16.199345          Saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox" with version "1.19-windows"
00:00:16.201652          Finished saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox"
00:00:16.202674 DeleteVM Saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox" with version "1.19-windows"
00:00:16.205175 DeleteVM Finished saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox"
00:00:16.280285          Platform architecture set to 'x86'
00:00:17.153874          Saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox" with version "1.19-windows"
00:00:17.156035          Finished saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox"
00:00:17.243290          Platform architecture set to 'x86'
00:00:17.244403          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:17.304652          Platform architecture set to 'x86'
00:00:17.305879          Saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox" with version "1.19-windows"
00:00:17.308136          Finished saving settings file "D:\slots\5\boinc_1b5c3652ffb02f04\boinc_1b5c3652ffb02f04.vbox"
00:00:17.536675          Platform architecture set to 'x86'
00:00:17.565212          Saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:17.566886          Finished saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml"
00:00:17.567036          Saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox" with version "1.19-windows"
00:00:17.569393          Finished saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox"
00:00:17.570233 DeleteVM Saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox" with version "1.19-windows"
00:00:17.572106 DeleteVM Finished saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox"
00:00:18.340146          Saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox" with version "1.19-windows"
00:00:18.342479          Finished saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox"
00:00:18.443148          Platform architecture set to 'x86'
00:00:18.444228          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={e36a5081-a82a-40bd-9e4e-42a44d6ce50f} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:18.526621          Platform architecture set to 'x86'
00:00:18.528309          Saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox" with version "1.19-windows"
00:00:18.531444          Finished saving settings file "D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox"
00:00:18.800801          Saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:18.803558          Finished saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml"
00:00:18.803637          Saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:18.805611          Finished saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml"
00:00:18.807001 DeleteVM Saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:18.809313 DeleteVM Finished saving settings file "C:\Users\jslyn\.VirtualBox\VirtualBox.xml"
00:00:23.853839 main     VirtualBox: object deletion starts
00:00:23.856235 main     HostDnsMonitor: shutting down ...
00:00:23.856312 main     HostDnsMonitor: shut down
00:00:23.894236 Watcher  ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={d644ad1e-c501-4fc7-9ab6-aa6d763bc540} aComponent={VirtualBoxWrap} aText={The object is not ready}, preserve=false aResultDetail=0
00:00:23.894754 main     VirtualBox: object deleted

    VM Execution Log:


    VM Startup Log:


    VM Trace Log:

escription: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#2 speed: unknown
Processor#2 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#3 speed: unknown
Processor#3 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#4 speed: unknown
Processor#4 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#5 speed: unknown
Processor#5 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#6 speed: unknown
Processor#6 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#7 speed: unknown
Processor#7 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#8 speed: unknown
Processor#8 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#9 speed: unknown
Processor#9 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#10 speed: unknown
Processor#10 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#11 speed: unknown
Processor#11 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#12 speed: unknown
Processor#12 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#13 speed: unknown
Processor#13 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#14 speed: unknown
Processor#14 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Processor#15 speed: unknown
Processor#15 description: 11th Gen Intel(R) Core(TM) i7-11700K @ 3.60GHz
Memory size: 65395 MByte
Memory available: 44135 MByte
Operating system: Windows 11
Operating system version: 10.0.26100

2025-01-21 22:54:04 (19104): 
Command: VBoxManage -q showvminfo "boinc_66f3979161914023" --machinereadable 
Exit Code: -2135228415
Output:
VBoxManage.exe: error: Could not find a registered machine named 'boinc_66f3979161914023'
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 3212 of file VBoxManageInfo.cpp

2025-01-21 22:54:05 (19104): 
Command: VBoxManage -q createvm --name "boinc_66f3979161914023" --basefolder "D:\slots\15" --ostype "Linux26_64" --register
Exit Code: 0
Output:
Virtual machine 'boinc_66f3979161914023' is created and registered.
UUID: 7a280b26-8b83-4ab9-b129-551105d1ccb3
Settings file: 'D:\slots\15\boinc_66f3979161914023\boinc_66f3979161914023.vbox'

2025-01-21 22:54:05 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --description "Theory_2773-2967445-185_2" 
Exit Code: 0
Output:

2025-01-21 22:54:05 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --memory 630 
Exit Code: 0
Output:

2025-01-21 22:54:05 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --cpus 1 
Exit Code: 0
Output:

2025-01-21 22:54:06 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --acpi on --ioapic on --rtcuseutc off 
Exit Code: 0
Output:

2025-01-21 22:54:06 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --vram 16 --graphicscontroller VBoxVGA 
Exit Code: 0
Output:

2025-01-21 22:54:06 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --boot1 disk --boot2 dvd --boot3 none --boot4 none 
Exit Code: 0
Output:

2025-01-21 22:54:07 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --nic1 nat --natdnsproxy1 on --cableconnected1 off 
Exit Code: 0
Output:

2025-01-21 22:54:07 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --cableconnected1 on 
Exit Code: 0
Output:

2025-01-21 22:54:07 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --usb off 
Exit Code: 0
Output:

2025-01-21 22:54:07 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --uart1 off --uart2 off 
Exit Code: 0
Output:

2025-01-21 22:54:08 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --lpt1 off --lpt2 off 
Exit Code: 0
Output:

2025-01-21 22:54:08 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --audio-enabled off 
Exit Code: 0
Output:

2025-01-21 22:54:08 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --clipboard disabled 
Exit Code: 0
Output:

2025-01-21 22:54:09 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --draganddrop disabled 
Exit Code: 0
Output:

2025-01-21 22:54:09 (19104): 
Command: VBoxManage -q storagectl "boinc_66f3979161914023" --name "Hard Disk Controller" --add "sata" --controller "IntelAHCI" --hostiocache off --portcount 3
Exit Code: 0
Output:

2025-01-21 22:54:14 (19104): 
Command: VBoxManage -q showhdinfo "D:\/projects/lhcathome.cern.ch_lhcathome/Theory_2025_01_16_prod.vdi" 
Exit Code: 0
Output:
UUID:           6a4110e9-e559-4c1c-bfd2-ba6f6aaf4169
Parent UUID:    base
State:          created
Type:           multiattach
Location:       D:\projects\lhcathome.cern.ch_lhcathome\Theory_2025_01_16_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       20480 MBytes
Size on disk:   781 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576
Child UUIDs:    547e99ac-8d6a-4e22-b312-28bb5a5872f7
                46f3e493-0814-4888-a97e-0a690a919173
                f306f8b8-ab16-4d4f-a870-27e7240ff64a

2025-01-21 22:54:15 (19104): 
Command: VBoxManage -q storageattach "boinc_66f3979161914023" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "D:\/projects/lhcathome.cern.ch_lhcathome/Theory_2025_01_16_prod.vdi" 
Exit Code: 0
Output:

2025-01-21 22:54:15 (19104): 
Command: VBoxManage -q storageattach "boinc_66f3979161914023" --storagectl "Hard Disk Controller" --port 1 --device 0 --type dvddrive --medium "C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso" 
Exit Code: 0
Output:

2025-01-21 22:54:15 (19104): 
Command: VBoxManage -q bandwidthctl "boinc_66f3979161914023" add "boinc_66f3979161914023_net" --type network --limit 1024G 
Exit Code: 0
Output:

2025-01-21 22:54:15 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --natpf1 ",tcp,127.0.0.1,56398,,80" 
Exit Code: 0
Output:

2025-01-21 22:54:16 (19104): 
Command: VBoxManage -q list extpacks
Exit Code: 0
Output:
Extension Packs: 1
Pack no. 0:   Oracle VirtualBox Extension Pack
Version:        7.1.4
Revision:       165100
Edition:        
Description:    Oracle Cloud Infrastructure integration, Host Webcam, VirtualBox RDP, PXE ROM, Disk Encryption, NVMe, full VM encryption.
VRDE Module:    VBoxVRDP
Crypto Module:  VBoxPuelCrypto
Usable:         true
Why unusable:   

2025-01-21 22:54:16 (19104): 
Command: VBoxManage -q modifyvm "boinc_66f3979161914023" --vrde on --vrdeextpack default --vrdeauthlibrary default --vrdeauthtype null --vrdeport 56419 --vrde-property "Security/Method=RDP" 
Exit Code: 0
Output:

2025-01-21 22:54:16 (19104): 
Command: VBoxManage -q sharedfolder add "boinc_66f3979161914023" --name "shared" --hostpath "D:\slots\15/shared"
Exit Code: 0
Output:

2025-01-21 22:54:21 (19104): 
Command: VBoxManage -q startvm "boinc_66f3979161914023" --type headless
Exit Code: -2147467259
Output:
VBoxManage.exe: error: Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
VBoxManage.exe: error: VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED)
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component ConsoleWrap, interface IConsole
Waiting for VM "boinc_66f3979161914023" to power on...

2025-01-21 22:54:21 (19104): 
Command: VBoxManage -q snapshot "boinc_66f3979161914023" list 
Exit Code: -108
Output:
This machine does not have any snapshots

2025-01-21 22:54:21 (19104): 
Command: VBoxManage -q bandwidthctl "boinc_66f3979161914023" remove "boinc_66f3979161914023_net" 
Exit Code: 0
Output:

2025-01-21 22:54:22 (19104): 
Command: VBoxManage -q unregistervm "boinc_66f3979161914023" --delete 
Exit Code: 0
Output:
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

2025-01-21 22:54:27 (19104): called boinc_finish(-2147467259)

</stderr_txt>
]]>


©2025 CERN