This error indicates that the network link is down. The network driver does not provide any further details. It is normal for some network cards to take a few seconds to establish the link. You may therefore see messages such as: net0: 52:54:00:12:34:56 using rtl8139 on PCI00:03.0 (open) [Link:down, TX:0 TXE:0 RX:0 RXE:0] [Link status: Down (http://ipxe.org/38086101)] Waiting for link-up on net0... ok These messages are not a cause for concern; this is expected behaviour for these network cards. However, if you see a message such as Waiting for link-up on net0... failed: Down (http://ipxe.org/38086101) then you should check that the cable is plugged in, and that any link lights are on.