today based on SLES 12 SP2, i'm using the imbeded QEMU to create a VM like below steps.

1. create one image for the VM using below command.
qemu-img -f create qcow2 /images/vm1.qcow2 8G
successuflly perofmed. the image was generated in the specific category.

2. Create the VM using the qemu-system-x86_64 command to install the Guest OS , using below comamnd:
qemu-system-x86_64 -m 512 -smp 4 --enable-kvm boot order=dc -hda /root/howl/vm1.qcow2 -cdrom /root/howl/SLES_SP1_x86_64.iso

when execute this command, error occurs like below:
Unable to init server: Could not connect: connection refused:
gtk initialization failed.

i don't understand this much, could anyone kindly give your suggestions here? thanks very much.