Planning to have stacking using ethernet port in X440 24P switch,when you say port 25 and 26, does it means its the 23 and 24 port or the 21 and 2 optical port? I supposed port 23 and 24, need some confirmation.
You can only stack with 10G ports. The 440 comes with either cooper stacking ports (which are 10G) or with 10G ports that can be configured to be stacking. You can not use 1G for stacking.