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I have the first world problem that my home requires more than one WiFi access point (AP) to have coverage throughout the house.

PROBLEM

My wired router, directly connected and adjacent to my cable modem, loses Internet connectivity as soon as I connect either of two WiFi routers that are in bridge mode (i.e. DHCP disabled, connected via a LAN port, not WAN). More details below.

DISCLOSURES

My Internet connection is new (switch from U-verse to Charter) but the other components of the network remain the same.

My home house wiring is Category 5e. I wired and terminated them myself. I am confident in the wiring for two reasons: 1) I employ a wire tester and they pass. 2) The LAN was functioning fine with U-verse. 3rd reason) I'm obsessive compulsive :-)

GEAR AND LOCATIONS

My Charter connection terminates in my basement utility room (referred to as MDF).

ROUTER

  • Hardware: LINKSYS ETHERFAST BEFSR11 BROADBAND ROUTER
  • Firmware version 1.40.2v (Released 10OCT2001)
  • Deployment location: MDF (Basement)
  • IP: 192.168.1.1
  • Subnet mask: 255.255.255.0
  • DHCP Enabled, scope: 192.168.1.100 <=> 254
  • Connected to Cable Model via WAN port.

(My Access Points were placed at two other locations previously, connected via a home run of Ethernet (distance < 200 ft.). However for troubleshooting they're now all in the MDF, connected via patch cables.)

AP1

  • Hardware: D-LINK DIR-601
  • Hardware version: A1
  • Firmware version 1.04B02 (updated on 26JAN2014)
  • Deployment Location: Upstairs Hallway Closet
  • Hard-coded IP: 192.168.1.3
  • SSID: juli-net
  • DHCP disabled via admin
  • Connected via LAN Port 4

AP2

  • Hardware: TP-LINK TL-WR541G
  • Hardware version:
  • Deployment Location: Guest Room
  • Hard-coded IP: 192.168.1.2
  • SSID: wifi-are-thou-romeo
  • DHCP disabled via admin
  • Connected via LAN Port 3

TEST CASE

  1. Power cycle the Cable Modem with the LINKSYS off. Wait for all green.
  2. Remove all cables from the LAN ports on the LINKSYS.
  3. Power up the LINKSYS, wait for all green.
  4. Connect a PC via patch cable.
  5. Await DHCP to assign an IP.
  6. Use ipconfig to confirm IP, Subnet Mask, Gateway: 192.168.1.100, 255.255.255.0, 192.168.1.1
  7. ping -t google.com and watch. Response times of 50ms
  8. Add a LAN cable to the LINKSYS LAN port. Insert the other end into the LAN port on AP1.
  9. Power AP1. wait for all green.
  10. Immediately the ping console starts reporting a variety of errors, including general error(!), request timeout, destination cannot be reached.
  11. Cut the power to AP1. The ping recovers immediately if done within a minute or so.
  12. (This occurs regardless if it's AP1 or AP2)

TROUBLESHOOTING UNDERTAKEN

  • My original conclusion was that there were IP conflicts between the various devices. In factory setting, the NETGEAR and the DLINK wanted 192.168.1.1 and the TPLINK wanted 192.168.0.1. That's why I fixed each IP as indicated above, to not conflict. However as I want them to be dumb wifi bridges, I'm not sure what the IP is good for except to allow me to admin each via browser (and its assigned IP for the URL)
  • The NETGEAR has an DHCP table available in its admin. However I can never access the admin after I power either AP so I can't confirm DHCP is working for the APs. However my laptop get an IP right away (see TEST CASE step 6 and 7).
  • When the APs are powered, I can connect to the WLAN successfully. However both OSX and Windows report "no Internet access". DHCP works sporadically via the wireless connection. When it does, I cannot ping google. It does show the gateway as being 192.168.1.1 (the IP of the LINKSYS). I didn't think to attempt to ping the gateway, but I will test this and edit.
  • Confirmed that DHCP is, in fact, disabled on the APs. This is difficult to do. I often have to factory reset the APs just to allow me to connect to the admin interface.
  • I've tested both APs as routers. I factory reset them, power cycle the cable modem and use the WAN port. I can use the Internet. However I only have WiFi coverage in one room in my house in this scenario: the basement utility room!

QUESTIONS

  • Is this configuration valid?
  • What can be concluded from the fact that the APs arriving on the network disrupt connectivity?
  • Do the APs need IP addresses? Do they have a function besides hosting the admin interface?
  • Can all WiFi routers be bridges? Is a Wireless router with DHCP disabled and connected to another DHCP device via a LAN port a bridge by definition? or does its chipset have to have support that could be missing from these devices?
  • Are there valid alternative configurations? E.g. can I have all three function as routers, but as different LAN segments, with non-overlapping DHCP ranges? I believe the subnet mask plays a role here, but I don't remember well and this seems needlessly complicated.
  • Any other suggestions?
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1 Answer 1

Both objects you call APs are actually routers. You are right in disabling DHCP and connecting them via LAN side plugs, but you should not assign IP addresses to either one. Connected this way, they will be acting as switches: i.e., they will be forwarding packets via MAC addresses, not IP addresses. You should remove the IP address, and let your main router figure it out all by itself.

After you have done, pls state whether and how the symptoms have changed.

share|improve this answer
    
Thank you. I wasn't able to see via either admin panel for the devices, that they should get their IP via DHCP. However I will go down that path more aggressively based on your guidance and report back. –  tedneigerux Jan 27 at 17:08
    
a co-worker suggested looking to see if UPnP is enabled on either/both router(s). Something else I'll be looking for. –  tedneigerux Jan 27 at 19:16
    
I disabled UPnP on AP1 and I'm using it now to write this message. Partial success. AP2 already had UPnP disabled and would still disrupt connectivity if I powered it up on the network now. –  tedneigerux Jan 28 at 4:50

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