We would like to remind you that the End of General Support (EOGS) for VMware vSphere 5.5 and vSAN 5.5 is September 19, 2018:
To maintain your full level of Support and Subscription Services, VMware recommends upgrading to vSphere 6.5 or vSphere 6.7. Note that by upgrading to vSphere 6.5/6.7, you not only get all the latest capabilities of vSphere but can also take advantage of the latest capabilities and release of vSAN, which is licensed separately.
VMware vCloud Suite 5 and vSphere with Operations Management customers running vSphere 5.5 are also recommended to upgrade to vSphere 6.5/6.7.
If you need help upgrading, please call the TIC Help Desk at 617 884-1086.