After Stacking 2 Switches X670-48t with both switches port 47-48 with Extreme 10306 SFP+ Cable. My switch port 45 and 46 not able to working with copper connected with port 45 and 46.
When you stack the X670-48T, X670 or X670v-48x with SummitStack-V, ports 47,48 are stacking and ports 45 & 46 are sacrificed and not able to be used. This is because the PHY for them control 4 of the ports. When you enable stacking-support that PHY is converted to stacking and therefore not able to be used. Here are is the stacking information sheet... Please see the note on the X670 - http://documentation.extremenetworks.com/summit/Summit_Family_HW_Install/Stacking/c_using-the-summit...
NOTE: Ports 45 and 46 are not available as data ports when the alternate stacking ports are used.