MarkHaysHarris777 wrote:We're both right; and for the record, I'm seldom wrong... and in this case I'm absolutely correct.
I'm going to correct you on one thing.
MarkHaysHarris777 wrote:... in other words, by mach address, you assign the same 'reserved' address to that mach address "dynamically".
There's no such thing as mach address, you mean MAC (media access control) address. It's also known as an Ethernet Address or Physical Address but not mach address.
As for the address on the device itself or static ip via dhcp both have their merits (even for servers). There are a few cases where you should have a static ip configured (dhcp servers, routers, firewalls) but after that both options have advantages: configured static (servers keep running if dhcp is broken), static via dhcp (easier to roll out network changes to systems).
But recently, there was an upgrade to dnsmasq, from 2.75 to 2.76. After I followed that upgrade, the DHCP result changed. I don't know if it's the upgrade or the recompilation cause the trick.
From memory that might be broken behaviour based on the rfc specs. I recall that the dhcp server is supposed to store lease information to stable storage and should then re-assign the same address based on what it did previously. That is how the isc dhcp server works which is the reference implementation.
About using a single wire to connect Pi to PC, I personally used static IP either, however I read that there is a "link local IP address", maybe it could be used, I don't know how yet.
There is the 169.254 network used as a fall back, however it can't be used to get internet access as it wont give you a default route (how would you know what device is the router). If this setup is supported by the pi it would provide a means to get into the os and configure it to get on the main network.