Tunnel and SDWAN interface as Logical Loopback Interface

[abdul.qadir5001]

We want to use any logical interface like loopback interface (Loopback1) instead of physical interface (TenGigabitEthernet0/0/3) for below tunnel and sdwan configurations on Cisco SDWAN router C-8500 . The reason is that interface TenGigabitEthernet0/0/3 is towards ISP and we want to avoid frequent up/down of this physical interface. What is the effect of this change. Is it recommended or not. Please need your support

interface Tunnel1

 ip unnumbered TenGigabitEthernet0/0/3

 tunnel source TenGigabitEthernet0/0/3

 tunnel mode sdwan

interface Tunnel1

 ip unnumbered Loopback1

 tunnel source Loopback1

 tunnel mode sdwan

!

sdwan

 interface TenGigabitEthernet0/0/3

tunnel-interface

encapsulation ipsec

sdwan

 interface Loopback1

tunnel-interface

encapsulation ipsec

interface Loopback1

ip address 2.2.2.2 255.255.255.255

end

[Kanan Huseynli]

Hi,

how will you avoid up/down event if it will happen in any case (based on my understanding you have frequent flaps).

You will lose physical port which affects transport for loopback for control and data path (bfd) will flap.