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HaroldWho 06-11-2013 12:59 PM

Router assigns 192.168.1.4 Although .3 and .2 are Not Busy
 
My Verizon router has always assigned 192.168.1.2 to my desktop. Recently I had guests who connected when I was not, and they were assigned 1.2.168.1.2 and .3 When I connected I got .4

Now I always get .4, even though the router shown no connections to .3 or .2

It's not a biggie, but is IS puzzling.

Doc CPU 06-12-2013 02:35 AM

Hi there,

Quote:

Originally Posted by HaroldWho (Post 4969728)
My Verizon router has always assigned 192.168.1.2 to my desktop. Recently I had guests who connected when I was not, and they were assigned 1.2.168.1.2 and .3 When I connected I got .4

Now I always get .4, even though the router shown no connections to .3 or .2

It's not a biggie, but is IS puzzling.

at a first glance, that my be puzzling, alright. But if you think about the strategy these SOHO routers usually use with their built-in DHCP servers, it's not that surprising any more.

Basically, they maintain a cross-reference list of MAC and assigned IP addresses, and when a device returns later, it is usually given the same IP again. If a new, yet unknown device comes along and asks for an IP, however, it will get the first available one.

So what happened is obvious: Your PC wasn't connected when the two guest PCs hooked up. They were unknown so far, so they got the first two available IPs .2 and .3 (.1 is the router itself, I guess). The record about your own PC, which used to have the .2, was now overwritten. A bit later, your own PC joined the network, and since the record referring to it was overwritten, it was considered a new device and got the first available IP, which was .4 now.
From then on, your router would remember that your PC had the .4 and assign that IP again and again.

Restarting the router may or may not erase this table, so that after that you might get the .2 again.

[X] Doc CPU

HaroldWho 06-12-2013 01:23 PM

Thanks Doc! Mystery solved. Now I can stop searching my HDD fora file that contains "192.168.1.4" :-)


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