Guest fencing on a RHEL KVM host not working

I have an issue, and still looking to resolve it.

my steps as below:

fence_xvm -o list

node1 f238c4a1-d6ce-e920-a5af-70fbc62b3203 on
node2 608b396f-becb-5e54-081a-692301aee064 on

after some times,

fence_xvm -o list

Timed out waiting for response
Operation failed

I always need to restart fence_virtd service on host machine in order to get the listing again.

I am using rhel 6.5 for host and vms,

fence-virt-0.2.3-15.el6.x86_64
fence-agents-3.1.5-35.el6.x86_64

I also tried to add transport using udpu as suggested in few blogs as well as red hat KB.