qm start ID returns "malformed JSON string"

[Jack_9846]

Minor emergency here, a Windows server 2016 VM was reset while it wasn't responding (which was because the nfs share one of its drives was on was disconnected), now when attempting to start it from the shell returns:

malformed JSON string, neither tag, array, object, number, string or atom, at character offset 0 (before "(end of string)") at /usr/share/perl5/PVE/Tools.pm line 949, <GEN25> chunk 1.

I really don't know where to go from here, any help would be great.

 

[Jack_9846]

Also this is linux kernel 4.13.8-3, and the output of qm showcmd ID --pretty is:

/usr/bin/kvm \
-id 200 \
-name NAME \
-chardev 'socket,id=qmp,path=/var/run/qemu-server/200.qmp,server,nowait' \
-mon 'chardev=qmp,mode=control' \
-pidfile /var/run/qemu-server/200.pid \
-daemonize \
-smbios 'type=1,uuid=f45c8d4a-1b83-4395-84eb-be17b312f1e7' \
-smp '4,sockets=1,cores=4,maxcpus=4' \
-nodefaults \
-boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' \
-vga std \
-vnc unix:/var/run/qemu-server/200.vnc,x509,password \
-no-hpet \
-cpu 'kvm64,+lahf_lm,+sep,+kvm_pv_unhalt,+kvm_pv_eoi,hv_spinlocks=0x1fff,hv_vapic,hv_time,hv_reset,hv_vpindex,hv_runtime,hv_relaxed,enforce' \
-m 16000 \
-device 'pci-bridge,id=pci.2,chassis_nr=2,bus=pci.0,addr=0x1f' \
-device 'pci-bridge,id=pci.1,chassis_nr=1,bus=pci.0,addr=0x1e' \
-device 'piix3-usb-uhci,id=uhci,bus=pci.0,addr=0x1.0x2' \
-readconfig /usr/share/qemu-server/pve-usb.cfg \
-device 'usb-tablet,id=tablet,bus=uhci.0,port=1' \
-device 'usb-host,vendorid=0x059f,productid=0x1024,id=usb0' \
-chardev 'socket,path=/var/run/qemu-server/200.qga,server,nowait,id=qga0' \
-device 'virtio-serial,id=qga0,bus=pci.0,addr=0x8' \
-device 'virtserialport,chardev=qga0,name=org.qemu.guest_agent.0' \
-iscsi 'initiator-name=iqn.1993-08.org.debian:01:f754cb6ece4b' \
-drive 'file=/data1/images/200/vm-200-disk-1.qcow2,if=none,id=drive-virtio0,format=qcow2,cache=none,aio=native,detect-zeroes=on' \
-device 'virtio-blk-pci,drive=drive-virtio0,id=virtio0,bus=pci.0,addr=0xa,bootindex=100' \
-netdev 'type=tap,id=net0,ifname=tap200i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on' \
-device 'virtio-net-pci,mac=7A:B4:77:91:E1:B1,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300' \
-rtc 'driftfix=slew,base=localtime' \
-global 'kvm-pit.lost_tick_policy=discard'


My JSON knowledge is not high enough to find out what's gone wrong here though.

 

[admintmt]

Hello! I've got the same error but on attempt to make stop mode backup
Here is my topic https://forum.proxmox.com/threads/proxmox-5-2-1-backup-issue.44272/
but i didn't receive any answer. Appreciate any help

 

[wolfgang]

Hi Jack_9846,

Can you please send the output of

pveversion -v

and when do you get this error or where do you see this error.

 

[wolfgang]

This is already known and fixed.
https://git.proxmox.com/?p=pve-common.git;a=commit;h=893ec6f2597c41dd048488534df1d2b6603639d8

It will come the next day in the repo.

 

[Jack_9846]

Thank you wolfgang! That makes my life easier (to be clear, you are talking about my issue too, not just @adminimt's, correct?). If you still want to look at it the version output is:

proxmox-ve: 5.2-2 (running kernel: 4.13.8-3-pve)
pve-manager: 5.2-2 (running version: 5.2-2/b1d1c7f4)
pve-kernel-4.15: 5.2-2
pve-kernel-4.15.17-2-pve: 4.15.17-10
pve-kernel-4.13.8-3-pve: 4.13.8-30
pve-kernel-4.13.4-1-pve: 4.13.4-26
corosync: 2.4.2-pve5
criu: 2.11.1-1~bpo90
glusterfs-client: 3.8.8-1
ksm-control-daemon: 1.2-2
libjs-extjs: 6.0.1-2
libpve-access-control: 5.0-8
libpve-apiclient-perl: 2.0-4
libpve-common-perl: 5.0-32
libpve-guest-common-perl: 2.0-16
libpve-http-server-perl: 2.0-9
libpve-storage-perl: 5.0-23
libqb0: 1.0.1-1
lvm2: 2.02.168-pve6
lxc-pve: 3.0.0-3
lxcfs: 3.0.0-1
novnc-pve: 1.0.0-1
proxmox-widget-toolkit: 1.0-18
pve-cluster: 5.0-27
pve-container: 2.0-23
pve-docs: 5.2-4
pve-firewall: 3.0-11
pve-firmware: 2.0-4
pve-ha-manager: 2.0-5
pve-i18n: 1.0-6
pve-libspice-server1: 0.12.8-3
pve-qemu-kvm: 2.11.1-5
pve-xtermjs: 1.0-5
qemu-server: 5.0-28
smartmontools: 6.5+svn4324-1
spiceterm: 3.0-5
vncterm: 1.5-3
zfsutils-linux: 0.7.9-pve1~bpo9

 

[wolfgang]

Yes, this is the same one.

This error always occurs if you start a VM.
But it is harmless and does nothing.

 

[Jack_9846]

Ah, I guess I wasn't clear enough, the VM does not start when this error is thrown.

 

[wolfgang]

What happens if you start it manually?

qm showcmd <VMID>  | . /dev/stdin

 

[Jack_9846]

It returns:

kvm: -netdev type=tap,id=net0,ifname=tap200i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on: could not configure /dev/net/tun (tap200i0): Device or resource busy


So the JSON problem was an unrelated red herring?

 

[wolfgang]

So the JSON problem was an unrelated red herring?

Normally you should be able to start the VM.
The JSON comes from the qemu output and not from the config.

 

[Jack_9846]

Ok, thank you, and the problem was fixed by restarting the node.