As part of my day-job I manage a couple of xenserver pools. I've been working through the old ones, bringing them up to xenserver 6.5 from a range of older versions 5.5, 6.0, 6.1, and 6.2
Many of the VMs now have an older version of xenserver tools installed. On the VM's General tab it says something like
Virtualisation state: Tools out of date (version 5.5 installed)
Virtualisation state: Tools out of date (version 6.0 installed)
Or confusingly
Virtualisation state: Optimised (version 6.2 installed)
What are the potential downsides for leaving the VMs as-is? Are there possible performance or reliability issues? This question is not about whether xentools should be installed, its aimed at whether updates to tools are important.