Comment 4 for bug 1283516

for linux-lng-arndale and linux-lng-preempt-rt-arndale:
The "kvm-boot-1 fail" is due to kvm.qcow2.gz isn't downloaded by wget or curl correctly.

solution may be:
1. check network connection, make it stable, and
2. add sanity check in the test script, if former step fails, cancel all the following steps which depends on the former one.