We have one Cisco switch with 1000base-LX GBIC connecting to 3500 switch. Since the switch 3500 is located in a room without air condition and heating, we will replace it with 2955s that comes with 100 GBIC. By my understanding, we need to buy CIS-GLC-FE-100LX to replace the 1000base-LX GBIC for 3750 switch.
The below is the configuration for 1000base-LX GBIC. Do I need to make change on this configuration if I replace 1000base-LX GBIC with CIS-GLC-FE-100LX?
switchport trunk encapsulation dot1q
switchport mode trunk
no ip address
No, You dont have to reset the switch. Just change the interface number and have rest of the commands under it. you should be fine.make sure you save the changes "wr mem".
The config under the interface doesn't have to change but you'll probably lose the configuration because the interface will no longer be Ge1/0/27 but something else like fe1/0/27.