So we have two EX4300 in a VC. Lets call the VC J-SWITCH1
Then we have another environment that consists of two cisco switch stacks, each stack has 2 members.
Lets call them C-SWITCH1 and C-SWITCH2
Between C-SWITCH1 and C-SWITCH2 there is a LACP channel.
So I need to connect J-SWITCH1 to the network that C-SWITCH1/2 has access to and there are several ways
Option1:
I could connect J-SWITCH1 to C-SWITCH1 with one cable. This would work but if the switch in C-SWITCH1 that J-SWTCH1 is connected to breaks, things will go down
Option2:
I could make a LACP LAG between both switches in J-SWITCH1 and both switches in C-SWITCH1. This would survive a single switch breaking. However when I upgrade C-SWITCH1 all switches needs to reboot at the same time (thanks Cisco) so that would break
Option3:
I could create 2 LACP LAGs from J-SWITCH1 to both C-SWITCH1 and C-SWITCH2. However then I would create a loop and need to consider spanning tree between the switches which I would rather avoid
Option4:
The best option would be if I could create a LAG in J-SWITCH1, which is Active/Passive. I could then connect one cable from the top switch in J-SWITCH1 to the top switch in C-SWITCH1, and a cable from the bottom switch in J-SWITCH1 to the top switch in C-SWITCH2.
If only one cable is active at one time no loop would be created. Also when we upgrade C-SWITCH1 it would then disable the cable loosing link, and bring up the second interface.
I know you can do this behaviour in linux, firewalls even in HP teaming. But is it possible in Juniper?