Task 9713693
| Name | 07959129_14_0 |
| Workunit | 7678222 |
| Created | 26 Sep 2020, 9:04:56 UTC |
| Sent | 26 Sep 2020, 21:53:23 UTC |
| Report deadline | 1 Oct 2020, 21:53:23 UTC |
| Received | 28 Sep 2020, 11:39:36 UTC |
| Server state | Over |
| Outcome | Computation error |
| Client state | Aborted by user |
| Exit status | 203 (0x000000CB) EXIT_ABORTED_VIA_GUI |
| Computer ID | 8978 |
| Run time | 2 hours 23 min 54 sec |
| CPU time | 44 min 50 sec |
| Validate state | Invalid |
| Credit | 0.00 |
| Device peak FLOPS | 1.00 GFLOPS |
| Application version | boinc2docker v1.14 (vbox64_mt) x86_64-apple-darwin |
| Peak working set size | 1.79 GB |
| Peak swap size | 10.05 GB |
| Peak disk usage | 227.39 MB |
Stderr output
<core_client_version>7.16.11</core_client_version>
<![CDATA[
<message>
aborted by user</message>
<stderr_txt>
2020-09-27 14:01:02 (25463): vboxwrapper (7.7.26199): starting
2020-09-27 14:01:02 (25463): Feature: Checkpoint interval offset (119 seconds)
2020-09-27 14:01:02 (25463): Detected: VirtualBox VboxManage Interface (Version: 6.1.6)
2020-09-27 14:01:02 (25463): Detected: Sandbox Configuration Enabled
2020-09-27 14:01:02 (25463): Detected: Minimum checkpoint interval (600.000000 seconds)
2020-09-27 14:01:02 (25463): Create VM. (boinc_151fc1295688350c, slot#2)
2020-09-27 14:01:02 (25463): Updating drive controller type and model for desired configuration.
2020-09-27 14:01:03 (25463): Setting Memory Size for VM. (3072MB)
2020-09-27 14:01:03 (25463): Setting CPU Count for VM. (1)
2020-09-27 14:01:03 (25463): Setting Chipset Options for VM.
2020-09-27 14:01:03 (25463): Setting Boot Options for VM.
2020-09-27 14:01:03 (25463): Setting Network Configuration for NAT.
2020-09-27 14:01:03 (25463): Enabling VM Network Access.
2020-09-27 14:01:03 (25463): Disabling USB Support for VM.
2020-09-27 14:01:03 (25463): Disabling COM Port Support for VM.
2020-09-27 14:01:03 (25463): Disabling Audio Support for VM.
2020-09-27 14:01:03 (25463): Disabling Clipboard Support for VM.
2020-09-27 14:01:03 (25463): Disabling Drag and Drop Support for VM.
2020-09-27 14:01:03 (25463): Adding storage controller(s) to VM.
2020-09-27 14:01:03 (25463): Adding virtual ISO 9660 disk drive to VM. (vm_isocontext.iso)
2020-09-27 14:01:04 (25463): Adding VirtualBox Guest Additions to VM.
2020-09-27 14:01:04 (25463): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2020-09-27 14:01:04 (25463): Enabling shared directory for VM.
2020-09-27 14:01:04 (25463): Starting VM. (boinc_151fc1295688350c, slot#2)
2020-09-27 14:01:05 (25463): Successfully started VM. (PID = '25518')
2020-09-27 14:01:05 (25463): Reporting VM Process ID to BOINC.
2020-09-27 14:01:05 (25463): Guest Log: BIOS: VirtualBox 6.1.6
2020-09-27 14:01:05 (25463): Guest Log: CPUID EDX: 0x178bfbff
2020-09-27 14:01:05 (25463): Guest Log: BIOS: No PCI IDE controller, not probing IDE
2020-09-27 14:01:06 (25463): VM state change detected. (old = 'poweroff', new = 'running')
2020-09-27 14:01:06 (25463): Preference change detected
2020-09-27 14:01:06 (25463): Setting CPU throttle for VM. (30%)
2020-09-27 14:01:06 (25463): Setting checkpoint interval to 600 seconds. (Higher value of (Preference: 60 seconds) or (Vbox_job.xml: 600 seconds))
2020-09-27 14:01:08 (25463): Guest Log: BIOS: Boot : bseqnr=1, bootseq=0032
2020-09-27 14:01:08 (25463): Guest Log: int13_harddisk: function 02, unmapped device for ELDL=80
2020-09-27 14:01:08 (25463): Guest Log: BIOS: Boot from Hard Disk 0 failed
2020-09-27 14:01:08 (25463): Guest Log: BIOS: Boot : bseqnr=2, bootseq=0003
2020-09-27 14:01:08 (25463): Guest Log: BIOS: Booting from CD-ROM...
2020-09-27 14:01:09 (25463): Guest Log: BIOS: KBD: unsupported int 16h function 03
2020-09-27 14:01:09 (25463): Guest Log: BIOS: AX=0305 BX=0000 CX=0000 DX=0000
2020-09-27 14:01:41 (25463): Guest Log: vgdrvHeartbeatInit: Setting up heartbeat to trigger every 2000 milliseconds
2020-09-27 14:01:41 (25463): Guest Log: vboxguest: misc device minor 56, IRQ 20, I/O port d020, MMIO at 00000000f0400000 (size 0x400000)
2020-09-27 14:01:41 (25463): Guest Log: net.ipv4.ip_forward = 1
2020-09-27 14:01:41 (25463): Guest Log: sysctl: cannot stat /proc/sys/net/ipv6/conf/all/forwarding: No such file or directory
2020-09-27 14:01:41 (25463): Guest Log: sysctl: setting key "cannot stat %s": No such file or directory
2020-09-27 14:01:41 (25463): Guest Log: sysctl: "cannot stat %s" is an unknown key
2020-09-27 14:01:41 (25463): Guest Log: sysctl: setting key "cannot stat %s": No such file or directory
2020-09-27 14:01:41 (25463): Guest Log: Segmentation fault
2020-09-27 14:01:41 (25463): Guest Log: automount ...
2020-09-27 14:01:41 (25463): Guest Log: Is the disk unpartitioned?, test for the 'boot2docker format-me' string
2020-09-27 14:01:42 (25463): Guest Log: automount over.
2020-09-27 14:01:42 (25463): Guest Log: [1;32mSetting hostname to [1;35mboot2docker[0;39m [1;32mDone.[0;39m
2020-09-27 14:01:42 (25463): Guest Log: Sun Sep 27 14:01:39 UTC 2020 dhcp -------------------------------
2020-09-27 14:01:47 (25463): Guest Log: udevadm settle - timeout of 5 seconds reached, the event queue contains:
2020-09-27 14:01:47 (25463): Guest Log: /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:00/PNP0700:00 (1352)
2020-09-27 14:01:48 (25463): Guest Log: Sun Sep 27 14:01:45 UTC 2020 dhcp -------------------------------
2020-09-27 14:01:48 (25463): Guest Log: VBoxService 5.0.16 r105871 (verbosity: 0) linux.amd64 (Mar 4 2016 17:38:55) release log
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.000070 main Log opened 2020-09-27T14:01:46.010999000Z
2020-09-27 14:01:48 (25463): Guest Log: VBoxService 5.0.16 r105871 (verbosity: 0) linux.amd64 (Mar 4 2016 17:38:55) release log
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.000070 main Log opened 2020-09-27T14:01:46.010999000Z
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.003867 main OS Product: Linux
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.003929 main OS Release: 4.1.19-boot2docker
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.003983 main OS Version: #1 SMP Sun Apr 17 19:40:54 UTC 2016
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.004036 main Executable: /sbin/VBoxService
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.004037 main Process ID: 870
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.004038 main Package type: LINUX_64BITS_GENERIC
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.003800:00:00.005807 main 5.0.16 r105871 started. Verbose level = 0
2020-09-27 14:01:48 (25463): Guest Log: 67 main OS Product: Linux
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.003929 main OS Release: 4.1.19-boot2docker
2020-09-27 14:01:48 (25463): Guest Log: 000:00:00.096415 vminfo rtldrNativeLoad: dlopen('libdbus-1.so.3', RTLD_NOW | RTLD_LOCAL) failed: libdbus-1.so.3: cannot open shared object file: No such file or directory
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.096542 vminfo Error: Unable to connect to system D-Bus (1/3): D-Bus not installed
2020-09-27 14:01:48 (25463): Guest Log: 0:00:00.003983 main OS Version: #1 SMP Sun Apr 17 19:40:54 UTC 2016
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.004036 main Executable: /sbin/VBoxService
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.004037 main Process ID: 870
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.004038 main Package type: LINUX_64BITS_GENERIC
2020-09-27 14:01:48 (25463): Guest Log: 00:00:00.005807 main 5.0.16 r105871 started. Verbose level = 0
2020-09-27 14:01:48 (25463): Guest Log: Mounting BOINC shared/...
2020-09-27 14:01:48 (25463): Guest Log: -------------------
2020-09-27 14:01:48 (25463): Guest Log: Sun Sep 27 12:01:48 UTC 2020
2020-09-27 14:01:53 (25463): Guest Log: 00:00:05.097969 vminfo Error: Unable to connect to system D-Bus (2/3): D-Bus not installed
2020-09-27 14:01:53 (25463): Guest Log: Sun Sep 27 12:01:53 UTC 2020
2020-09-27 14:01:53 (25463): Guest Log: 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
2020-09-27 14:01:53 (25463): Guest Log: link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2020-09-27 14:01:53 (25463): Guest Log: inet 127.0.0.1/8 scope host lo
2020-09-27 14:01:53 (25463): Guest Log: valid_lft forever preferred_lft forever
2020-09-27 14:01:53 (25463): Guest Log: inet6 ::1/128 scope host
2020-09-27 14:01:53 (25463): Guest Log: valid_lft forever preferred_lft forever
2020-09-27 14:01:53 (25463): Guest Log: 2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default
2020-09-27 14:01:53 (25463): Guest Log: link/ether 5e:68:b7:e1:5e:3d brd ff:ff:ff:ff:ff:ff
2020-09-27 14:01:53 (25463): Guest Log: 3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
2020-09-27 14:01:53 (25463): Guest Log: link/ether 08:00:27:ab:9e:61 brd ff:ff:ff:ff:ff:ff
2020-09-27 14:01:54 (25463): Guest Log: inet 10.0.2.15/24 brd 10.0.2.255 scope global eth0
2020-09-27 14:01:54 (25463): Guest Log: valid_lft forever preferred_lft forever
2020-09-27 14:01:54 (25463): Guest Log: inet6 fe80::a00:27ff:feab:9e61/64 scope link
2020-09-27 14:01:54 (25463): Guest Log: valid_lft forever preferred_lft forever
2020-09-27 14:01:54 (25463): Guest Log: -------------------
2020-09-27 14:01:54 (25463): Guest Log: Linking /etc/docker to /var/lib/boot2docker for persistence
2020-09-27 14:01:54 (25463): Guest Log: Waiting for Docker daemon to start...
2020-09-27 14:01:55 (25463): Guest Log: REPOSITORY TAG IMAGE ID CREATED SIZE
2020-09-27 14:01:55 (25463): Guest Log: Running boinc_app...
2020-09-27 14:01:55 (25463): Guest Log: Importing Docker image from BOINC...
2020-09-27 14:01:55 (25463): Guest Log: Filesystem Size Used Available Use% Mounted on
2020-09-27 14:01:55 (25463): Guest Log: tmpfs 2.6G 164.2M 2.5G 6% /
2020-09-27 14:01:55 (25463): Guest Log: tmpfs 1.5G 0 1.5G 0% /dev/shm
2020-09-27 14:01:55 (25463): Guest Log: cgroup 1.5G 0 1.5G 0% /sys/fs/cgroup
2020-09-27 14:01:55 (25463): Guest Log: shared 112.8G 96.6G 16.2G 86% /root/shared
2020-09-27 14:01:55 (25463): Guest Log: tmpfs 2.6G 164.2M 2.5G 6% /var/lib/docker/aufs
2020-09-27 14:01:58 (25463): Guest Log: 00:00:10.158423 vminfo Error: Unable to connect to system D-Bus (3/3): D-Bus not installed
2020-09-27 14:02:28 (25463): Guest Log: doing docker load...
2020-09-27 14:03:05 (25463): Guest Log: Filesystem Size Used Available Use% Mounted on
2020-09-27 14:03:05 (25463): Guest Log: tmpfs 2.6G 631.9M 2.0G 23% /
2020-09-27 14:03:05 (25463): Guest Log: tmpfs 1.5G 0 1.5G 0% /dev/shm
2020-09-27 14:03:05 (25463): Guest Log: cgroup 1.5G 0 1.5G 0% /sys/fs/cgroup
2020-09-27 14:03:05 (25463): Guest Log: shared 112.8G 96.4G 16.4G 85% /root/shared
2020-09-27 14:03:05 (25463): Guest Log: tmpfs 2.6G 631.9M 2.0G 23% /var/lib/docker/aufs
2020-09-27 14:03:05 (25463): Guest Log: total used free shared buff/cache available
2020-09-27 14:03:05 (25463): Guest Log: Mem: 3007 51 2286 631 669 2286
2020-09-27 14:03:05 (25463): Guest Log: Swap: 701 0 701
2020-09-27 14:03:05 (25463): Guest Log: Building apps directory...
2020-09-27 14:03:47 (25463): Guest Log: Prerun diagnostics...
2020-09-27 14:03:47 (25463): Guest Log: REPOSITORY TAG IMAGE ID CREATED SIZE
2020-09-27 14:03:47 (25463): Guest Log: nanohub_apps_base 11 42db2bf7db3d 2 years ago 458.1 MB
2020-09-27 14:03:47 (25463): Guest Log: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
2020-09-27 14:03:47 (25463): Guest Log: 467.8M /var/lib/docker
2020-09-27 14:03:47 (25463): Guest Log: total used free shared buff/cache available
2020-09-27 14:03:47 (25463): Guest Log: Mem: 3007 51 2285 631 671 2286
2020-09-27 14:03:47 (25463): Guest Log: Swap: 701 0 701
2020-09-27 14:03:47 (25463): Guest Log: Filesystem Size Used Available Use% Mounted on
2020-09-27 14:03:47 (25463): Guest Log: tmpfs 2.6G 631.9M 2.0G 23% /
2020-09-27 14:03:47 (25463): Guest Log: tmpfs 1.5G 0 1.5G 0% /dev/shm
2020-09-27 14:03:47 (25463): Guest Log: cgroup 1.5G 0 1.5G 0% /sys/fs/cgroup
2020-09-27 14:03:47 (25463): Guest Log: shared 112.8G 96.5G 16.3G 86% /root/shared
2020-09-27 14:03:47 (25463): Guest Log: tmpfs 2.6G 631.9M 2.0G 23% /var/lib/docker/aufs
2020-09-27 14:03:47 (25463): Guest Log: Running...
2020-09-27 14:03:48 (25463): Guest Log: 07959129_14.boinc
2020-09-27 14:03:48 (25463): Guest Log: 07959129_14.sh
2020-09-27 14:06:14 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:06:24 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:12:18 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:12:28 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:12:48 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:13:09 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:19:42 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:19:52 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:20:13 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:20:32 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:28:07 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:28:17 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:35:14 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:35:52 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:37:42 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:37:53 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:39:13 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:39:33 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:41:25 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:41:34 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:43:46 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:44:05 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:44:25 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:44:35 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:51:18 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:51:39 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:54:31 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:54:41 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:55:01 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:55:11 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:55:21 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:55:31 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:56:12 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:56:52 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 14:57:54 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 14:58:03 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:00:34 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:00:54 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:04:45 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:05:26 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:05:36 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:05:46 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:06:16 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:06:37 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:11:19 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:11:29 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:16:41 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:17:11 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:19:12 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:19:22 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:23:35 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:23:45 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:23:54 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:26:16 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:26:35 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:26:46 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:33:19 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:33:29 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:33:40 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:33:50 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:38:31 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:38:52 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:39:12 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:39:33 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:40:22 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:40:32 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:41:13 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:41:33 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:44:25 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:44:55 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:49:46 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:50:07 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:51:17 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:51:38 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:52:59 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:53:08 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:53:19 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:53:39 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:54:11 (25463): Status Report: Elapsed Time: '6000.868510'
2020-09-27 15:54:11 (25463): Status Report: CPU Time: '1867.470000'
2020-09-27 15:56:00 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:56:10 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 15:57:31 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 15:57:41 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 16:37:20 (25463): VM state change detected. (old = 'running', new = 'paused')
2020-09-27 16:37:29 (25463): VM state change detected. (old = 'paused', new = 'running')
2020-09-27 16:38:56 (25463): Powering off VM.
2020-09-27 16:38:57 (25463): Successfully stopped VM.
</stderr_txt>
]]>
©2024 COPYRIGHT 2017-2018 NCN