HP Virtual Connect 4Gb Fibre Channel Module for c-Class BladeSystem - Manual (Page 252)

Virtual Connect modules 252
If the VC domain is configured for double-dense server mode, and a profile is assigned to an empty
double-dense server bay, then a hot-plug installation of a single-dense server into the corresponding
single-dense server bay results in the profile not being activated because the profile is not assigned to the
single-dense server bay. To recover the profile, assign the profile to the single-dense server bay.