Why do I keep getting a new IP address

[007stuart]

I hope someone can explain why my current IP address is 192.168.0.138 when my network consists of 3 Laptops, 30 meg VM Superhub, Sonos Zonebridge and S5, D Link DSM 510 Wgps 606 and Iomega 2TB NAS, 2 samsung Andriod Phones 1 Iphone3gs and a TP Link WA 701ND working in repeater mode.

My Laptop connects via ethernet to the WA701ND as that is the only way to get decent connection. however momentarily the connerction is lost and on reconnection a fresh IP address is assigned. The others seem to be okay as their IP addresses are all in the range 192.168.0.1 -192.168.0.15

PS Now upto 192.168.0.139

[zekeisaszekedoes]

That's all part of DHCP.

It randomly assigns devices an IP address from the pool made available to it. For example, in my case any devices not given static addresses get any available from 10.0.0.100 through 10.0.0.200. Generally speaking it SHOULD be random each time, but I've found that the same MAC address tends to get the same IP address if it hasn't been taken by something else, but you have to factor in things like lease time, i.e. longer leases means you could lose your DHCP'd IP and get another anywhere else in the available range.

Personally I'd be more concerned about dropouts, especially when connected via ethernet.

[Kymmy]

How can it be the TP link when it's in repeater mode (i.e..wifi)?? The Superhub is the one giving out the DHCP to the ethernet clients and not the TP :rolleyes: The Superhub should be holding the lease and issuing out the same IP to the MAC on temp drop-outs which obviously it's not..

[edit] Original post deleted but will leave my answer up

[Peter_]

Misread so removed the post.

[zekeisaszekedoes]

Oh hang on... make sure DHCP is only enabled on ONE router, otherwise weird things start to happen.

[Kymmy]

Repeater mode will not DHCP so yes it is only enabled on one router ;)

[zekeisaszekedoes]

Repeater mode will not DHCP so yes it is only enabled on one router ;)

Depends on the firmware. It is entirely possible to accidentally leave the DHCP on when setting older versions of DD-WRT to bridge mode. I believe this has been remedied for a while though, but I'd wager that some badly-designed OEM firmware might allow you to keep it on even when it can cause problems.

[Kymmy]

Possibly, but the TP in repeater mode should use the WAN port as the input, as he's using ethernet the TP should not be able to DHCP anything that side of the router..

It does beg the question is it all set up correctly and as a test perhaps the TP should be turned off..

[007stuart]

Thanks for all the responses.

I have switched off the TP Link and have gone wireless "G". The IP address is now 192.168.0.85 and I will leave the laptop in this mode for a few hours to see how things do.

I have also as precaution returned the TP Link to its default status.

I will keep you posted

[007stuart]

Well it looks as if I have wrongly configured the TP Link as my IP adrrress has not changed since my last post.

I will try tomorrow and see how I do.

[007stuart]

Well I have reconnected the Tp Link as a Universal Repeater and all is well.

I guess I must have messed up the settings last time.

Thanks to those that repalied

[Kymmy]

As I said as a repeater it shouldn't have interfered.. It sounds as though it was more in bridged mode

[qasdfdsaq]

It depends on how the repeater operates, there's several different types of repeater mode and the nomenclature isn't standardized - some repeaters *do* perform DHCP, some operate as a double-NAT, some operate in bridge mode. They can mess things up simply out of inconsistency.

[zekeisaszekedoes]

It depends on how the repeater operates, there's several different types of repeater mode and the nomenclature isn't standardized - some repeaters *do* perform DHCP, some operate as a double-NAT, some operate in bridge mode. They can mess things up simply out of inconsistency.

Thanks for verifying, this is certainly consistent with my experience and exactly what I suspected.