Task 1739645

Name 07186371_301_0
Workunit 1265003
Created 25 Apr 2019, 20:20:27 UTC
Sent 25 Apr 2019, 23:45:16 UTC
Report deadline 30 Apr 2019, 23:45:16 UTC
Received 26 Apr 2019, 21:45:46 UTC
Server state Over
Outcome Computation error
Client state Compute error
Exit status 196 (0x000000C4) EXIT_DISK_LIMIT_EXCEEDED
Computer ID 874
Run time 5 min 39 sec
CPU time 3 min 8 sec
Validate state Invalid
Credit 0.00
Device peak FLOPS 3.02 GFLOPS
Application version boinc2docker v1.12 (vbox64_mt)
windows_x86_64
Peak working set size 79.85 MB
Peak swap size 92.18 MB
Peak disk usage 3.17 GB

Stderr output

<core_client_version>7.14.2</core_client_version>
<![CDATA[
<message>
Disk usage limit exceeded</message>
<stderr_txt>
2019-04-26 15:01:35 (7596): vboxwrapper (7.9.26200): starting
2019-04-26 15:01:35 (7596): Feature: Checkpoint interval offset (454 seconds)
2019-04-26 15:01:35 (7596): Detected: VirtualBox COM Interface (Version: 5.1.26)
2019-04-26 15:01:35 (7596): Detected: Minimum checkpoint interval (600.000000 seconds)
2019-04-26 15:01:35 (7596): Create VM. (boinc_6cbc6eeaa5419445, slot#1)
2019-04-26 15:01:35 (7596): Updating drive controller type and model for desired configuration.
2019-04-26 15:01:35 (7596): Setting Memory Size for VM. (3072MB)
2019-04-26 15:01:35 (7596): Setting CPU Count for VM. (1)
2019-04-26 15:01:35 (7596): Setting Chipset Options for VM.
2019-04-26 15:01:35 (7596): Setting Boot Options for VM.
2019-04-26 15:01:35 (7596): Enabling VM Network Access.
2019-04-26 15:01:35 (7596): Setting Network Configuration for NAT.
2019-04-26 15:01:35 (7596): Disabling USB Support for VM.
2019-04-26 15:01:35 (7596): Disabling COM Port Support for VM.
2019-04-26 15:01:35 (7596): Disabling LPT Port Support for VM.
2019-04-26 15:01:35 (7596): Disabling Audio Support for VM.
2019-04-26 15:01:35 (7596): Disabling Clipboard Support for VM.
2019-04-26 15:01:35 (7596): Disabling Drag and Drop Support for VM.
2019-04-26 15:01:35 (7596): Adding storage controller(s) to VM.
2019-04-26 15:01:35 (7596): Adding virtual ISO 9660 disk drive to VM. (vm_isocontext.iso)
2019-04-26 15:01:35 (7596): Adding VirtualBox Guest Additions to VM.
2019-04-26 15:01:35 (7596): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2019-04-26 15:01:35 (7596): Enabling shared directory for VM.
2019-04-26 15:01:36 (7596): Starting VM. (boinc_6cbc6eeaa5419445, slot#1)
2019-04-26 15:01:45 (7596): Guest Log: BIOS: VirtualBox 5.1.26

2019-04-26 15:01:45 (7596): Guest Log: BIOS: Boot : bseqnr=1, bootseq=0032

2019-04-26 15:01:45 (7596): Guest Log: int13_harddisk: function 02, unmapped device for ELDL=80

2019-04-26 15:01:45 (7596): Guest Log: BIOS: Boot from Hard Disk 0 failed

2019-04-26 15:01:45 (7596): Guest Log: BIOS: Boot : bseqnr=2, bootseq=0003

2019-04-26 15:01:45 (7596): Guest Log: BIOS: Booting from CD-ROM...

2019-04-26 15:01:45 (7596): Successfully started VM. (PID = '16056')
2019-04-26 15:01:45 (7596): Reporting VM Process ID to BOINC.
2019-04-26 15:01:50 (7596): VM state change detected. (old = 'poweroff', new = 'running')
2019-04-26 15:02:00 (7596): Preference change detected
2019-04-26 15:02:00 (7596): Setting CPU throttle for VM. (100%)
2019-04-26 15:02:00 (7596): Setting checkpoint interval to 600 seconds. (Higher value of (Preference: 60 seconds) or (Vbox_job.xml: 600 seconds))
2019-04-26 15:02:05 (7596): Guest Log: BIOS: KBD: unsupported int 16h function 03

2019-04-26 15:02:05 (7596): Guest Log: BIOS: AX=0305 BX=0000 CX=0000 DX=0000 

2019-04-26 15:02:15 (7596): Guest Log: vgdrvHeartbeatInit: Setting up heartbeat to trigger every 2000 milliseconds

2019-04-26 15:02:15 (7596): Guest Log: vboxguest: misc device minor 56, IRQ 20, I/O port d020, MMIO at 00000000f0400000 (size 0x400000)

2019-04-26 15:02:20 (7596): Guest Log: net.ipv4.ip_forward = 1

2019-04-26 15:02:20 (7596): Guest Log: sysctl: cannot stat /proc/sys/net/ipv6/conf/all/forwarding: No such file or directory

2019-04-26 15:02:20 (7596): Guest Log: sysctl: setting key "cannot stat %s": No such file or directory

2019-04-26 15:02:20 (7596): Guest Log: sysctl: "cannot stat %s" is an unknown key

2019-04-26 15:02:20 (7596): Guest Log: sysctl: setting key "cannot stat %s": No such file or directory

2019-04-26 15:02:20 (7596): Guest Log: Segmentation fault

2019-04-26 15:02:20 (7596): Guest Log: automount ...

2019-04-26 15:02:20 (7596): Guest Log: Is the disk unpartitioned?, test for the 'boot2docker format-me' string

2019-04-26 15:02:20 (7596): Guest Log: automount over.

2019-04-26 15:02:20 (7596): Guest Log: Setting hostname to boot2docker Done.

2019-04-26 15:02:20 (7596): Guest Log: Fri Apr 26 15:02:15 UTC 2019 dhcp -------------------------------

2019-04-26 15:02:25 (7596): Guest Log: udevadm settle - timeout of 5 seconds reached, the event queue contains:

2019-04-26 15:02:25 (7596): Guest Log:   /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:00/PNP0700:00 (1347)

2019-04-26 15:02:25 (7596): Guest Log: Fri Apr 26 15:02:21 UTC 2019 dhcp -------------------------------

2019-04-26 15:02:25 (7596): Guest Log: VBoxService 5.0.16 r105871 (verbosity: 0) linux.amd64 (Mar  4 2016 17:38:55) release log

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.000121 main     Log opened 2019-04-26T15:02:21.596353000Z

2019-04-26 15:02:25 (7596): Guest Log: VBoxService 5.0.16 r105871 (verbosity: 0) linux.amd64 (Mar  4 2016 17:38:55) release log

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.000121 main     Log opened 2019-04-26T15:02:21.596353000Z

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.003797 main     OS Product: Linux

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.003892 main     OS Release: 4.1.19-boot2docker

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004065 main     OS Version: #1 SMP Sun Apr 17 19:40:54 UTC 2016

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004203 main     Executable: /sbin/VBoxService

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004211 main     Process ID: 771

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004212 main     Package type: LINUX_64BITS_GENERIC

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.003797 main     OS Product: Linux

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.003892 main     OS Release: 4.1.19-boot2docker

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004065 main     OS Version: #1 SMP Sun Apr 17 19:40:54 UTC 2016

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004203 main     Executable: /sbin/VBoxService

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004211 main     Process ID: 771

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.004212 main     Package type: LINUX_64BITS_GENERIC

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.017385 main     5.0.16 r105871 started. Verbose level = 0

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.017385 main     5.0.16 r105871 started. Verbose level = 0

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.023850 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

2019-04-26 15:02:25 (7596): Guest Log: 00:00:00.023929 vminfo   Error: Unable to connect to system D-Bus (1/3): D-Bus not installed

2019-04-26 15:02:25 (7596): Guest Log: Mounting BOINC shared/...

2019-04-26 15:02:25 (7596): Guest Log: -------------------

2019-04-26 15:02:25 (7596): Guest Log: Fri Apr 26 20:02:22 UTC 2019

2019-04-26 15:02:30 (7596): Guest Log: 00:00:05.025902 vminfo   Error: Unable to connect to system D-Bus (2/3): D-Bus not installed

2019-04-26 15:02:30 (7596): Guest Log: Fri Apr 26 20:02:51 UTC 2019

2019-04-26 15:02:30 (7596): Guest Log: 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default 

2019-04-26 15:02:30 (7596): Guest Log:     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

2019-04-26 15:02:30 (7596): Guest Log:     inet 127.0.0.1/8 scope host lo

2019-04-26 15:02:30 (7596): Guest Log:        valid_lft forever preferred_lft forever

2019-04-26 15:02:30 (7596): Guest Log: 2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default 

2019-04-26 15:02:30 (7596): Guest Log:     link/ether a6:e5:98:d3:f8:9f brd ff:ff:ff:ff:ff:ff

2019-04-26 15:02:30 (7596): Guest Log: 3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000

2019-04-26 15:02:30 (7596): Guest Log:     link/ether 08:00:27:60:0c:5f brd ff:ff:ff:ff:ff:ff

2019-04-26 15:02:30 (7596): Guest Log:     inet 10.0.2.15/24 brd 10.0.2.255 scope global eth0

2019-04-26 15:02:30 (7596): Guest Log:        valid_lft forever preferred_lft forever

2019-04-26 15:02:30 (7596): Guest Log: -------------------

2019-04-26 15:02:30 (7596): Guest Log: Linking /etc/docker to /var/lib/boot2docker for persistence

2019-04-26 15:02:30 (7596): Guest Log: Waiting for Docker daemon to start...

2019-04-26 15:02:30 (7596): Guest Log: REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

2019-04-26 15:02:30 (7596): Guest Log: Running boinc_app...

2019-04-26 15:02:30 (7596): Guest Log: Importing Docker image from BOINC...

2019-04-26 15:02:30 (7596): Guest Log: Filesystem                Size      Used Available Use% Mounted on

2019-04-26 15:02:30 (7596): Guest Log: tmpfs                     2.6G    164.2M      2.5G   6% /

2019-04-26 15:02:30 (7596): Guest Log: tmpfs                     1.5G         0      1.5G   0% /dev/shm

2019-04-26 15:02:30 (7596): Guest Log: cgroup                    1.5G         0      1.5G   0% /sys/fs/cgroup

2019-04-26 15:02:30 (7596): Guest Log: shared                  931.3G    456.2G    475.1G  49% /root/shared

2019-04-26 15:02:30 (7596): Guest Log: tmpfs                     2.6G    164.2M      2.5G   6% /var/lib/docker/aufs

2019-04-26 15:02:35 (7596): Guest Log: 00:00:10.027841 vminfo   Error: Unable to connect to system D-Bus (3/3): D-Bus not installed

2019-04-26 15:02:40 (7596): Guest Log: doing docker load...

2019-04-26 15:02:59 (7596): Guest Log: Filesystem                Size      Used Available Use% Mounted on

2019-04-26 15:02:59 (7596): Guest Log: tmpfs                     2.6G    663.1M      2.0G  24% /

2019-04-26 15:02:59 (7596): Guest Log: tmpfs                     1.5G         0      1.5G   0% /dev/shm

2019-04-26 15:02:59 (7596): Guest Log: cgroup                    1.5G         0      1.5G   0% /sys/fs/cgroup

2019-04-26 15:02:59 (7596): Guest Log: shared                  931.3G    456.0G    475.3G  49% /root/shared

2019-04-26 15:02:59 (7596): Guest Log: tmpfs                     2.6G    663.1M      2.0G  24% /var/lib/docker/aufs

2019-04-26 15:02:59 (7596): Guest Log:               total        used        free      shared  buff/cache   available

2019-04-26 15:02:59 (7596): Guest Log: Mem:           3007          48        2256         663         701        2257

2019-04-26 15:02:59 (7596): Guest Log: Swap:           699           0         699

2019-04-26 15:02:59 (7596): Guest Log: Building apps directory...

2019-04-26 15:07:22 (7596): Powering off VM.
2019-04-26 15:07:23 (7596): Successfully stopped VM.
2019-04-26 15:07:28 (7596): Deregistering VM. (boinc_6cbc6eeaa5419445, slot#1)
2019-04-26 15:07:28 (7596): Removing virtual disk drive(s) from VM.
2019-04-26 15:07:28 (7596): Removing network bandwidth throttle group from VM.
2019-04-26 15:07:28 (7596): Removing storage controller(s) from VM.
2019-04-26 15:07:28 (7596): Removing VM from VirtualBox.

    Hypervisor System Log:

32:03:13.364052          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:13.417059          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:25.089541          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:25.749125          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:25.750125          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:28.322952          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:28.324452          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:28.327453          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:32.966542          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:32.967542          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:32.967542          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:34.626252          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:36.268961          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:36.705016          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:38.605258          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:38.653264          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:39.289845          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:39.651891          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:41.290099          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:42.845796          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:42.849297          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
32:03:42.851297          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:42.851797          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:42.889302          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:42.894802          ERROR [COM]: aRC=VBOX_E_INVALID_OBJECT_STATE (0x80bb0007) aIID={4afe423b-43e0-e9d0-82e8-ceb307940dda} aComponent={MediumWrap} aText={Medium 'C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso' is locked for reading by another task}, preserve=false aResultDetail=0
32:03:42.904304          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={4afe423b-43e0-e9d0-82e8-ceb307940dda} aComponent={MediumWrap} aText={The object is not ready}, preserve=false aResultDetail=0
32:03:42.904804          ERROR [COM]: aRC=VBOX_E_INVALID_OBJECT_STATE (0x80bb0007) aIID={4afe423b-43e0-e9d0-82e8-ceb307940dda} aComponent={MediumWrap} aText={Medium 'C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso' is locked for reading by another task}, preserve=false aResultDetail=0
32:03:43.608893          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:43.663900          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:44.292980          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:44.662027          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:46.295234          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:48.613029          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:48.668536          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:49.303116          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:49.665662          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
32:03:51.304370          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={b2547866-a0a1-4391-8b86-6952d82efaa0} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0

    VM Execution Log:


    VM Startup Log:


    VM Trace Log:

15:07:38 (7596): called boinc_finish(194)

</stderr_txt>
]]>


©2024 COPYRIGHT 2017-2018 NCN