VMware’s CEO Paul Maritz has blamed a chunk of leftover pre-release code for a bug that prevented virtual servers from powering up when the clock hit 12 August. Despite the company carrying out quality assurance of its product, VMware failed to spot that it had released the leftover bit of time-bombed code within the ESX 3.5 and ESXi 3.5 Update 2 final versions of its hypervisors that were released about two weeks ago.

The code time bomb prevented virtual machines from powering on or leaving suspend mode and unable to migrate using the firm's VMotion software. Maritz said VMware has released an express patch for customers unlucky enough to have already installed or upgraded to ESX or ESXi 3.5u2. This is a temporary work-around that requires sys admins to turn the clock back to kick-start virtual machines and imagine that 12 August was just a bad dream. However this may be inadequate since it’s a regulatory requirement in many businesses to timestamp server transactions.

Maritz added “We are doing everything in our power to make sure this doesn’t happen again. VMware prides itself on the quality and reliability of our products, and this incident has prompted a thorough self-examination of how we create and deliver products to our customers. We have kicked off a comprehensive, in-depth review of our QA and release processes, and will quickly make the needed changes.

“I want to apologise for the disruption and difficulty this issue may have caused to our customers and our partners. Your confidence in VMware is extremely important to us, and we are committed to restoring that confidence fully and quickly.”