CYRUSONE LP and CYRUSONE FINANCE CORP. as Issuers, CYRUSONE INC. as Guarantor, and WELLS FARGO BANK, N.A. as Trustee 2.900% SENIOR NOTES DUE 2024 FIRST SUPPLEMENTAL INDENTURE Dated as of December 5, 2019 TO THE INDENTURE Dated as of December 5, 2019