Exhibit 21.1

SUBSIDIARIES OF SWITCH & DATA FACILITIES COMPANY, INC. AS OF DECEMBER 31, 2009



|    |  |                                         |  |                             
|--- |  | --------------------------------------- |  | ----------------------------
|No. |  | Name of Subsidiary                      |  | Jurisdiction of Organization
|    |  |                                        
|1   |  | Switch & Data Holdings, Inc.            |  | Delaware                    
|    |  |                                        
|2   |  | Switch and Data Enterprises, Inc.       |  | Delaware                    
|    |  |                                        
|3   |  | Switch & Data Facilities Company LLC    |  | Delaware                    
|    |  |                                        
|4   |  | Switch and Data Operating Company LLC   |  | Delaware                    
|    |  |                                        
|5   |  | Switch and Data Management Company LLC  |  | Delaware                    
|    |  |                                        
|6   |  | Switch and Data Toronto, Ltd.           |  | Ontario                     
|    |  |                                        
|7   |  | Switch & Data AZ One LLC                |  | Delaware                    
|    |  |                                        
|8   |  | Switch & Data CA One LLC                |  | Delaware                    
|    |  |                                        
|9   |  | Switch & Data CA Two LLC                |  | Delaware                    
|    |  |                                        
|10  |  | Switch and Data CA Nine LLC             |  | Delaware                    
|    |  |                                        
|11  |  | Switch & Data CO One LLC                |  | Delaware                    
|    |  |                                        
|12  |  | Switch & Data FL One LLC                |  | Delaware                    
|    |  |                                        
|13  |  | Switch & Data FL Two LLC                |  | Delaware                    
|    |  |                                        
|14  |  | Switch & Data FL Four LLC               |  | Delaware                    
|    |  |                                        
|15  |  | Switch and Data FL Seven LLC            |  | Delaware                    
|    |  |                                        
|16  |  | Switch & Data GA One LLC                |  | Delaware                    
|    |  |                                        
|17  |  | Switch and Data GA Three LLC            |  | Delaware                    
|    |  |                                        
|18  |  | Switch & Data IL One LLC                |  | Delaware                    
|    |  |                                        
|19  |  | Switch & Data IN One LLC                |  | Delaware                    
|    |  |                                        
|20  |  | Switch & Data MA One LLC                |  | Delaware                    
|    |  |                                        
|21  |  | Switch & Data MI One LLC                |  | Delaware                    
|    |  |                                        
|22  |  | Switch & Data MO One LLC                |  | Delaware                    
|    |  |                                        
|23  |  | Switch & Data NY One LLC                |  | Delaware                    
|    |  |                                        
|24  |  | Switch and Data NY Four LLC             |  | Delaware                    
|    |  |                                        
|25  |  | Switch and Data NY Five LLC             |  | Delaware                    
|    |  |                                        
|26  |  | Switch & Data/NY Facilities Company LLC |  | Delaware                    
|    |  |                                        
|27  |  | Switch & Data OH One LLC                |  | Delaware                    
|    |  |                                        
|28  |  | Switch & Data PA Two LLC                |  | Delaware                    
|    |  |                                        
|29  |  | Switch and Data PA Three LLC            |  | Delaware                    
|    |  |                                        
|30  |  | Switch and Data PA Four LLC             |  | Delaware                    
|    |  |                                        
|31  |  | Switch & Data TN Two LLC                |  | Delaware                    
|    |  |                                        
|32  |  | Switch & Data TX One LLC                |  | Delaware                    
|    |  |                                        
|33  |  | Switch and Data TX Five LP              |  | Delaware                    
|    |  |                                        
|34  |  | Switch and Data Dallas Holdings I LLC   |  | Delaware                    
|    |  |                                        
|35  |  | Switch and Data Dallas Holdings II LLC  |  | Delaware                    
|    |  |                                        
|36  |  | Switch & Data VA One LLC                |  | Delaware                    
|    |  |                                        
|37  |  | Switch & Data VA Two LLC                |  | Delaware                    
|    |  |                                        
|38  |  | Switch and Data VA Four LLC             |  | Delaware                    
|    |  |                                        
|39  |  | Switch & Data WA One LLC                |  | Delaware                    
|    |  |                                        
|40  |  | Switch and Data WA Three LLC            |  | Delaware                    
|    |  |                                        
|41  |  | Switch and Data CA Eleven LLC           |  | Delaware                    
|    |  |                                        
|42  |  | Switch and Data NJ Two LLC              |  | Delaware                    
|    |  |                                        
|43  |  | Switch and Data GA Four LLC             |  | Delaware