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This is for fault tolerance in a client/server app. The business says that when the network is unavailable, the app must still run. And it will, provided it doesn't lose it's IP address. The problem is that I'm losing the IP address as soon as I unplug the NIC. Can I force it to use it's last known IP address?


option rfc3442-classless-static-routes code 121 = array of unsigned integer 8;

request subnet-mask, broadcast-address, routers,
    interface-mtu, host-name, domain-name, domain-search,
    domain-name-servers, nis-domain, nis-servers,
    nds-context, nds-servers, nds-tree-name,
    netbios-name-servers, netbios-dd-server,
    netbios-node-type, netbios-scope, ntp-servers;

require subnet-mask;

timeout 60;
retry 60;
reboot 10;
select-timeout 5;
initial-interval 2;

lease {
    interface "eth0";

Relevant system log output is here:

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Perhaps I'm missing something obvious, as happens from time to time, but isn't this the very thing static IP addresses assignments are for? Instead of using dhclient, set the IP to a static IP and be done with it.

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