ad-hoc ether network w/o dhcp

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http://www.linuxquestions.org – there's an option in dhcp to assign private subnet address when client can't get responce from dhcp server. I'm getting different behavior apparently when I connect network storage directly to eth port - the link would not establish with default automatic neither when manually enter ipv4 address. I can't get my data from backup)! is it a bug? (HowTos)