[ 623.146778][ T8100] Could not find device with ifindex 2000 in netnsfd 11 [ 623.147576][ T8100] Could not find netns with fd: 2000 [ 623.148152][ T8100] netdevsim netdevsim408 eth0: Cannot link a netdevsim to itself [ 623.149234][ T8100] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).