debian8 qemu中KVM對rbd的支持

升級qemu到2.4之後發現默認rbd支持關閉了，經過如下方法開啓對rbd的支持

qemu-system-x86_64 -drive format=?
Supported formats: qcow vdi vmdk host_cdrom host_floppy vhdx nbd host_device parallels cloop blkdebug null-aio null-co qcow2 qed sheepdog raw vvfat file vpc quorum bochs blkverify

qemu-system-x86_64 --version
QEMU emulator version 2.4.0 (Debian 1:2.4+dfsg-2), Copyright (c) 2003-2008 Fabrice Bellard

apt-get update&&apt-get install qemu-block-extra

qemu-system-x86_64 -drive format=?
Supported formats: qcow vdi iscsi vmdk host_cdrom host_floppy vhdx nbd host_device dmg parallels cloop blkdebug null-aio null-co qcow2 qed sheepdog tftp ftp raw ftps https rbd http ssh vvfat file vpc quorum bochs blkverify