I currently have two 3750's (stacked). We recently purchased two new 3850's and have stacked them as well. My question is, how to I trunk them? I want to be able to use the new switches with the same vlans and IP addresses as the existing. The new switches are in the same rack as the existing ones.
The current 3750's are the gateway for my network (and they will remain as such, for the time being).
I connected a fiber uplink from switch to switch as in:
3750a (gi 1/0/49) --> 3850a (gi 1/1/1)
3750b (gi 2/0/49) --> 3850b (gi 2/1/1)
I gave the fiber ports the following settings:
3750a:
int gi1/0/49
switchport trunk encaps dot1q
switchport trunk allowed vlan add ALL
switchport mode trunk
switchport nonegotiate
3750b
int gi2/0/49
switchport trunk encaps dot1q
switchport trunk allowed vlan add ALL
switchport mode trunk
switchport nonegotiate
3850a / 3850b:
Gi1/1/1
Gi2/1/1
switchport trunk allowed vlan add ALL
switchport mode trunk
switchport nonegotiate
At this point, I thought I would be able to ssh into the new (3850) switch and ping the current (3750), but I cannot. Network assistant on the curent 3750 switch "sees" the new 3850, but has it listed as "unsupported device". The swiches are on the same subnet (10.11.1.0 /24).
Gateway switch (3750) is 10.11.1.2 and new 3850 is 10.11.1.14. If I plug my laptop into the 3850 and give myself a 10.11.1.x IP, I can ping the switch itself (10.11.1.14), but I cannot ping the gateway (10.11.1.2). If I SSH into the switches, I cannot ping one another.
Do I need to set up the fiber uplinks as an Etherchannel? Or are my switchport settings incorrect? I'm not sure what I am missing. I am in no way an expert on this, so even if its something that may be obvious to others, it is entirely possible I overlooked it.
Hope this makes sense. Any suggestions would be appreciated. Thank you.
