tree /sys/class/net
/sys/class/net
├── docker0 -> ../../devices/virtual/net/docker0
├── eth0 -> ../../devices/pci0000:00/0000:00:1c.0/0000:01:00.0/net/eth0
├── lo -> ../../devices/virtual/net/lo
├── virbr0 -> ../../devices/virtual/net/virbr0
├── virbr0-nic -> ../../devices/virtual/net/virbr0-nic
└── wlan0 -> ../../devices/pci0000:00/0000:00:1c.3/0000:02:00.0/net/wlan0
ha van mogotte pci bus, akkor az valodi, ha meg ott a virtual akkor az nem valodi