System Management
7210 SAS M, T, X, R6 Basic System Configuration Guide Page 239
ref-order ptp [Must be configured] 
config> system> sync-if-timing> commit
Note: Now the Frequency and Time is provide by PTP [configure >system >ptp >no shutdown] 
only. This is a standalone PTP mode.
Example configuration on use of PTP and syncE references on 
7210 SAS-T
The configuration example for 7210 SAS-T showing use of PTP and syncE references 
simultaneously is as below:
*A:SAS-T-B>config>system>sync-if-timing# info detail 
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   ql-selection
         ref-order ptp ref1 ref2 --> All three reference can be configured simultaneously
   ref1
   source-port 1/1/1
   no shutdown
   no ql-override
   exit
   ref2
   source-port 1/1/7
   no shutdown
   no ql-override
   exit
   ptp
   no ql-override
   no shutdown
   exit
   revert
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