[  856.776191][ T7459] Could not find device with ifindex 2000 in netnsfd 11
[  856.776906][ T7459] Could not find netns with fd: 2000
[  856.777625][ T7459] Cannot link a netdevsim to itself
[  856.778284][ T7459] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).