Hey,
Is it possible to have two MAC addresses mapped to the same IP? Would it cause problems? Only one of them will be on the network (plugged in) at the same time.
Thanks!
two mac addresses, same static IP?
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Conradical
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Re: two mac addresses, same static IP?
best way to find out....... try?
Sounds like something that should work though. If it does I'd be using that.
Sounds like something that should work though. If it does I'd be using that.
Re: two mac addresses, same static IP?
There may be an issue immediately after you switch devices. Other devices on your network use their ARP tables to translate the IP address to the MAC address. They update these tables only periodically so before they refresh their tables there will be confusion as they continue to try and talk to the old MAC address (that was disconnected). After a period of time all the ARP tables will update and things will start working properly.
Linksys WRT1900ACv2
Netgear WNDR3700v2
TP Link 1043ND v3
TP-Link TL-WDR3600 v1
Buffalo WZR-HP-G300NH2
WRT54G-TM
Netgear WNDR3700v2
TP Link 1043ND v3
TP-Link TL-WDR3600 v1
Buffalo WZR-HP-G300NH2
WRT54G-TM
Re: two mac addresses, same static IP?
What if I were to set one of the devices to use a static IP from it's end.
The scenario I'm talking about is a user on my network has an XBox 360 and a desktop, but only has one cable, so he switches it back and forth. If the PC has a static IP hardcoded into the network connection dialog and the XBox is using DHCP, would that still cause the problems you talk about?
The switch would be pretty instant.
The scenario I'm talking about is a user on my network has an XBox 360 and a desktop, but only has one cable, so he switches it back and forth. If the PC has a static IP hardcoded into the network connection dialog and the XBox is using DHCP, would that still cause the problems you talk about?
The switch would be pretty instant.
Re: two mac addresses, same static IP?
Take your example the router is talking to the PC at 192.168.1.2. On the wire the MAC address is used by the hardware so your router must ask "Who has 192.168.1.2" and your PC responds with its MAC address. The router keeps this information in its ARP cache and directs all traffic destined for 192.168.1.2 to the MAC address it knows. If you switch the connection to the XBOX then the information the router has is not longer correct since the XBOX has a different MAC address.
With SSH you can issue a command to tell the router to reset its ARP cache or you can wait for the timeout in which case the router updates the cache on its own.
Not sure how long the timeout is but I think its 60 seconds.
With SSH you can issue a command to tell the router to reset its ARP cache or you can wait for the timeout in which case the router updates the cache on its own.
Not sure how long the timeout is but I think its 60 seconds.
Linksys WRT1900ACv2
Netgear WNDR3700v2
TP Link 1043ND v3
TP-Link TL-WDR3600 v1
Buffalo WZR-HP-G300NH2
WRT54G-TM
Netgear WNDR3700v2
TP Link 1043ND v3
TP-Link TL-WDR3600 v1
Buffalo WZR-HP-G300NH2
WRT54G-TM
Re: two mac addresses, same static IP?
Ah, ok, now I understand. Thanks 
So is there a way to lower the timeout from 60 seconds on openwrt/gargoyle? I can't seem to find where to set it. And is there a disadvantage to going lower, say 20 seconds? I suppose that it would be slower since the router has to ask for the correct MAC more often? The timeuot is 60 seconds from idle? or every 60 seconds?
So is there a way to lower the timeout from 60 seconds on openwrt/gargoyle? I can't seem to find where to set it. And is there a disadvantage to going lower, say 20 seconds? I suppose that it would be slower since the router has to ask for the correct MAC more often? The timeuot is 60 seconds from idle? or every 60 seconds?