Hi. On Fri, 13 Oct 2000, Gerhard Sittig wrote: [snip]
This is some braindead MS system with a failed DHCP attempt or some other "auto config" (i.e. not knowingly configured) network stuff.
Called APIPA
Somebody at MS had the bright idea to say "if we don't have / don't get an address, we simply dice us one." That's when they use the IPs you can see above. Watch the "wide" netmask and the broadcast for "the other unconfigured machines"! Seems MS wants to cope with ignorant environments and even run when not setup correctly ...
Better would be to power the system automatically down?
Sadly I couldn't find any reference to where those IPs come from. RFC1918 addresses are explicitely reserved at the registrars. Those MS fallbacks seem not to be. Do they collide in some future time with some other "customer"? Or are they registered and reserved and I'm just too blind to see? And - most important to solve the problem - is there a chance to teach those WinDoze machines the expected behaviour of "when you don't get an address, you don't have one"? I'm sick of seeing those things happen and realizing it's quite difficult to tell which machine has the problem (to go there and fix it) -- since the IP is so strange and out of the local subnet there won't be ARP entries pointing to the MAC of the NIC involved. One has to wait for the Doze user to call and whine "my computer can't see the net" (unless they're used to it and don't complain but boot again, instead).
You can find those adresses on whois:
whois -h whois.arin.net "169.254.0.0"
Netname: LINKLOCAL
Netblock: 169.254.0.0 - 169.254.255.255
They are specifically reserved for that purpose, but I couldn't find a RFC
on it.
But here is a list from my router with relevant denied routes:
# localhost
deny ip 127.0.0.0 0.255.255.255 any
# rfc 1918
deny ip 10.0.0.0 0.255.255.255 any
deny ip 172.16.0.0 0.15.255.255 any
deny ip 192.168.0.0 0.0.255.255 any
# reserved blocks
deny ip 0.0.0.0 0.255.255.255 any
deny ip 1.0.0.0 0.255.255.255 any
deny ip 2.0.0.0 0.255.255.255 any
deny ip 5.0.0.0 0.255.255.255 any
deny ip 7.0.0.0 0.255.255.255 any
deny ip 23.0.0.0 0.255.255.255 any
deny ip 27.0.0.0 0.255.255.255 any
deny ip 31.0.0.0 0.255.255.255 any
deny ip 36.0.0.0 1.255.255.255 any
deny ip 39.0.0.0 0.255.255.255 any
deny ip 41.0.0.0 0.255.255.255 any
deny ip 42.0.0.0 0.255.255.255 any
deny ip 49.0.0.0 0.255.255.255 any
deny ip 50.0.0.0 0.255.255.255 any
deny ip 58.0.0.0 1.255.255.255 any
deny ip 60.0.0.0 0.255.255.255 any
deny ip 67.0.0.0 0.255.255.255 any
deny ip 68.0.0.0 3.255.255.255 any
deny ip 72.0.0.0 7.255.255.255 any
deny ip 80.0.0.0 15.255.255.255 any
deny ip 96.0.0.0 15.255.255.255 any
deny ip 112.0.0.0 8.255.255.255 any
deny ip 120.0.0.0 3.255.255.255 any
deny ip 124.0.0.0 1.255.255.255 any
deny ip 126.0.0.0 0.255.255.255 any
deny ip 197.0.0.0 0.255.255.255 any
deny ip 218.0.0.0 1.255.255.255 any
deny ip 220.0.0.0 3.255.255.255 any
# former class E
deny ip 240.0.0.0 15.255.255.255 any
# microsoft APIPA
deny ip 169.254.0.0 0.0.255.255 any
greetings
olli
--
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Oliver Hensel