Kushal Das

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Quick way to get throw away VMs using Tunir

The latest Tunir package has a --debug option which can help us to get some quick vms up, where we can do some destructive work, and then just remove them. Below is an example to fire up two vms using Fedora Cloud base image using a quickjob.cfg file.

cpu = 1
ram = 1024

user = fedora
image = /home/Fedora-Cloud-Base-20141203-21.x86_64.qcow2

user = fedora
image = /home/Fedora-Cloud-Base-20141203-21.x86_64.qcow2

In the quickjob.txt file we just keep one command to check sanity :)

vm1 free -m

After we execute Tunir, we will something like below as output.

# tunir --multi quickjob
... lots of output ...

Non gating tests status:
DEBUG MODE ON. Destroy from /tmp/tmpiNumV2/destroy.sh

The above mention directory also has the temporary private key to login to the instances. The output also contains the IP addresses of the VM(s). We can login like

# ssh fedora@ -i /tmp/tmpiNumV2/private.pem -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no

The last two parts of the ssh command will make sure that we do not store the signature for the throwaway guests in the known_hosts file. To clean up afterwards we can do the following.

# sh /tmp/tmpiNumV2/destroy.sh