On the 7210 SAS-D, ref1 must be configured to use one of ports 1/1/1 to 1/1/4 and ref2 must be configured to use either port 1/1/5 or 1/1/6. The software enforces this check. Ports 1/1/7 to 1/1/10 can be configured as either ref1 or ref2.
There is no port restriction on the 7210 SAS-Dxp, 7210 SAS-K 2F1C2T, 7210 SAS-K 2F6C4T, or 7210 SAS-K 3SFP+ 8C; any port can be configured for ref1 or ref2.
config>system# sync-if-timing
config>system>sync-if-timing# begin
config>system>sync-if-timing# ref1
config>system>sync-if-timing>ref1# source-port 1/1/1
config>system>sync-if-timing>ref1# no shutdown
config>system>sync-if-timing>ref1# exit
config>system>sync-if-timing# ref2
config>system>sync-if-timing>ref2# source-port 1/1/2
config>system>sync-if-timing>ref2# no shutdown
config>system>sync-if-timing>ref2# exit
config>system>sync-if-timing>commit
*7210-SAS>config>system>sync-if-timing#info detail
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ref-order ref1 ref2
ref1
source-port 1/1/1
no shutdown
exit
ref2
source-port 1/1/2
no shutdown
exit
no revert
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