Allow Linux VM running on KVM paravirtualized environment to support disk hotplugging

In case you have a Linux OS VM running on KVM paravirtualized environment and found that it doesn't response to the new virtual disk you added (you dont see a new disk on dmesg or nothing coming up from fdisk -l), you will need to make sure virtio_blk driver is in place.


[root@vm ~]# lsmod | grep -i virtio
virtio_net             15665  0
virtio_balloon          4281  0
virtio_blk              5087  3
virtio_pci              6733  0
virtio_ring             7169  4 virtio_net,virtio_balloon,virtio_blk,virtio_pci
virtio                  4824  4 virtio_net,virtio_balloon,virtio_blk,virtio_pci


Indeed, you should be seeing /dev/vd* instead of /dev/sd* if you have picked correct OS type during VM initialization. In case you are seeing /dev/sd*, probably you didnt pick correct OS type and that caused virtio associated driver not being loaded.

[root@vm ~]# fdisk -l /dev/vda

Disk /dev/vda: 21.5 GB, 21474836480 bytes
16 heads, 63 sectors/track, 41610 cylinders
Units = cylinders of 1008 * 512 = 516096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0006fe0a

   Device Boot      Start         End      Blocks   Id  System
/dev/vda1   *           3         409      204800   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/vda2             409       41611    20765696   8e  Linux LVM
Partition 2 does not end on cylinder boundary.

Garbage / Missing fonts in RHEL Virt-manager

Virt-Manager is a X application which is capable to manage RHEL's XEN, QEMU/KVM, LXC service. Similar to other X application, it could be launched remotely via X11 Forwarding.

However, it happens that garbage fonts will be shown if the host is not installed with appropriate font package. To fix this, package dejavu-lgc-sans-fonts have to be installed.

[root@server ~]# yum -y install dejavu-lgc-sans-fonts