Spanning Tree Protocol and Backup Ethernet Interface

[akhasapetyan]

When we enable backup interface on interface by issuing command "ethernet backup interface" the spanning tree protocol stops functioning. The mentioned hardware is:

cisco ASR-920-24SZ-IM (Freescale P2020) processor (revision 1.2 GHz) with 893202K/6147K bytes of memory.
Processor board ID CAT2316V0MM
24 Gigabit Ethernet interfaces
4 Ten Gigabit Ethernet interfaces
32768K bytes of non-volatile configuration memory.
3670016K bytes of physical memory.
1231647K bytes of eMMC flash at bootflash:.

Cisco IOS XE Software, Version 16.11.01a
Cisco IOS Software [Gibraltar], ASR920 Software (PPC_LINUX_IOSD-UNIVERSALK9_NPE-M), Version 16.11.1a, RELEASE SOFTWARE (fc1)

Could someone help us to shed a light on this issue?

[paul driver]

Hello

---

@akhasapetyan wrote:

When we enable backup interface on interface by issuing command "ethernet backup interface" the spanning tree protocol stops functioning. The mentioned hardware is:

---

I assume this is in indeed a L2 interface as you mentions spanning-tree, If so when applying a flex-link by default stp is disabled on that interface.