[  522.738223] netdevsim netdevsim521 eni521np1: renamed from eth1
[  522.835541] netdevsim netdevsim504 eni504np1: renamed from eth0
[  523.061717] Could not find device with ifindex 2000 in netnsfd 11
[  523.061873] Could not find netns with fd: 2000
[  523.061954] Cannot link a netdevsim to itself
[  523.062042] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).