Experience with the infrastructure systems during the commissioning of the LHC

The commissioning activity which started in October 2005 consists in the short circuit tests, the commissioning of the non cryogenic systems and the finally the powering tests of the superconducting components of the LHC. During all theses phases, the infrastructure systems are brought into operation, their performance assessed and validated for the routine operation of the collider. This paper presents the experience gained during this activity and reports recent incidents with some infrastructure systems suggest that they could have a non negligible impact on the downtime of the LHC.