To assign DHCP form a single source or not?

I have a wireless network on a farm that extends for 16 kms. There are 5 various stops on the way where I have installed access points. The internet arrives on a Linksys E3000 that serves as a DHCP server as well.

Along the way I have APs for the local users also configured as DHCP, but using a different range of IP addresses.

What do the experts consider as best practice?

Cisco AP ip to Dlink AP ip to TP-Link Ap ip to

This is the general configuration at the moment.

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Access points (i.e. no router enabled) do NOT have DHCP servers. Only routers have DHCP servers. Your three AP's seem to be configured as routers, not AP's. There's no problem with doing it that way except:

  1. You end up with double NAT, which can cause problems with remote control programs and server based programs.
  2. You cannot connect between computers on different sub-nets.
  3. Switching from one AP to another results in a change of client IP.
  4. You cannot easily access the 3 routers from the internet because they have two traverse TWO routers.
  5. With one big DHCP scope, there's no need to subnet.
  6. If you're into security and are using a RADIUS server for authentication, the double NAT can create problems.

Unless you have complications that you didn't mention, methinks it would be better if you:

  1. Configure the three routers as access points.
  2. Disable the DHCP servers in the 3 access points.
  3. Move the backhaul cable from the "internet" port to the "LAN" port. More:

The one downside to using a single DHCP server is that if for some reason one of the connected access points is reset to defaults, the built in DHCP server will again become active. The symptom is that everything looks normal with IPCONFIG or ifconfig, but nothing gets to the internet. In order to more easily detect this problem, I've renumbered my networks to use something other than or which are the defaults for most routers. For example, my office network is If something gets reset, the connected client will show a address, which I know is wrong, and points to the obvious problem.
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Jeff Liebermann

for me - I like to have all my static IP stuff at the low end, then assign the DHCP ranges in nice numerical groups I can remember... ie - groups of 10, 20, 25, 50 - from each router or AP or on the 10's as you have BUT have them end on the 9's

02 - 19 static 20 - 29 09 40 - 59 19 60 - 69 09 70 - 89 19
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I have a Linksys "160N" router/WAP with the router and the WAN/Internet port not being used. It is connected to an existing Linksys BEFSX41 router which normally has the DHCP function. I just turned on the DHCP server in the 160N WAP, and connected to it... SO, if the OP is using "routers", but only configs the WAP portion, then the DHCP scenario would work.

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So far, so good.

Nope. You now have two DHCP servers. Assigning IP addresses is just part of the puzzle. You also have to deal with the default gateway. Both will set the default route to itself so that client computahs can connect to the interknot via the gateway router. However, your 2nd DHCP server is also pointing to itself, which is not the correct default route the internet. The symptoms are that everything looks like it works, with correct looking IP addresses, but any client that gets their DHCP assigned configuration from your "160N" thing, is not going to connect to the internet.

You can probably make this work if your router firmware allows setting the DHCP assigned default route to an IP address other than itself. Most low end routers don't offer this feature. DD-WRT and other alternative firmware have that feature. You can also make it work with RIP2.

Incidentally, make sure you don't duplicate IP addresses for the various routers.

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Jeff Liebermann

sorry - I should have been more specific... for the test, I turned on the 2nd DHCP server in the Linksys 160N router, with the router portion not plugged in or used - maybe like the OP has - just using one of the LAN ports connecting to other local Linksys BEFSX41 router.

The 2nd DHCP settings were are manually config'd to point to the correct DNS, Gateway, etc and used a different IP range than my norm router assigns..

It all worked fine - clients got all the correct settings, tested local & Internet - then turned it all off - back to just being WAP.

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That's the usual way. The DHCP service only works on the LAN side, not the WAN side.

Ummm... I don't see where one plugs in the default route (gateway) in the WRT160N v3 setup: The ones that can be used as a secondary DHCP server have a "gateway" setting on the DHCP config page.

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Jeff Liebermann

Jeff - you're right, I was too quick and didn't notice....

Had my Android & iPad reboot and looked at local access, and then tried Internet from one of them...didn't look at the IP Status/settings. One just grabbed/renewed it's old lease & settings - so it worked - and the other grabbed the new IP, but nothing for GW & DNS - so it didn't

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