volume is not needed to be created before installing. it can be done in one shot.
root@ve1100(Active)(/Common)(tmos) show sys software
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Sys::Software Status
Volume Product Version Build Active Status
--------------------------------------------------
HD1.1 BIG-IP 11.0.0 8037.0 no complete
HD1.2 BIG-IP 11.0.0 8131.0 yes complete
HD1.3 none none none no complete
root@ve1100(Active)(/Common)(tmos) install sys software hotfix Hotfix-BIGIP-11.0.0-8131.0-HF1.iso volume HD1.4 create-volume
root@ve1100(Active)(/Common)(tmos) show sys software
--------------------------------------------------------------
Sys::Software Status
Volume Product Version Build Active Status
--------------------------------------------------------------
HD1.1 BIG-IP 11.0.0 8037.0 no complete
HD1.2 BIG-IP 11.0.0 8131.0 yes complete
HD1.3 none none none no complete
HD1.4 BIG-IP 11.0.0 8037.0 no installing 0.000 pct