Home WiFi, Using a 2nd router as additional AP, what's wrong?

[kaon]

Hi all,
Do you see anything wrong with this arrangement?
I was under the impression that hooking up a common wireless-router via the numbered ports, rather than the WAN port, was the main thing to making it run like almost like a wireless switch, i.e. clients would receive DHCP from the upstream router.
The upstairs AP is consistently visible, but connecting to it is intermittent. Clients often get stuck on "acquiring network address".
(sorry, I just realized I don't know how to embed the image in the post body.)

Additional info:
I am giving the two router different SSIDs, example, kaon-L1 and kaon-L2.
old: kaon-L1 has channel 6 (with 40MHz width, wide channel: upper, status page says "Channel: 6+4")
kaon-L1 has channel 1 (standard 20MHz width)
kaon-L2 has channel 11
Both are using PSK WPA2-only, same password (is it OK to have the same password?)

after messing around with reboots and changing of SSID's, now one WinXP-SP3 netbook can see the internet wirelessly thru kaon-L2, (position: PC05).
But a BB9700 handset still cannot, even though it authenticates successfully, pageloading times out.

 

[overdrive31]

So PC04 doesn't have an issue with DHCP? I would have to say it's the SSID setup. You using separate SSIDs for each or are they identical? Make sure you're using non-overlapping channels like 1(router), 6(ap),or 11(ap). Some clients can't seem to roam very well when using identical SSIDs thus requiring the use of same channel as well, but this causes interference. If so try using separate SSIDs and channels. Good Luck

P.S. In Tim's article "When Wireless LANs Collide", he states that Windows XP Zero Config doesn't show multiple instances of the same network name, so roaming clients would only see one or the other not both. If it's trying to connect to the first floor AP, it could be the signal is too weak to establish an IP from DHCP.

 

[kaon]

So PC04 doesn't have an issue with DHCP? I would have to say it's the SSID setup. You using separate SSIDs for each or are they identical? Make sure you're using non-overlapping channels like 1(router), 6(ap),or 11(ap). Some clients can't seem to roam very well when using identical SSIDs thus requiring the use of same channel as well, but this causes interference. If so try using separate SSIDs and channels. Good Luck

Thanks.
Ever since the beginning, I've been using separate SSIDs. Although I did not touch the channel settings, (default: auto), until now. As described in my update to Post#1, I am using CH6 and CH11.
The downstairs router is fine, the problem is always with the upstairs router.
The issue I see is temperamental-ness that isn't SNR related, because I can bring the clients near the APs, (not too near of course), and the problems remain the same.
Also, there appears to be a "choosiness" about what machines can get to the internet thru it.

 

[overdrive31]

It could be the channel bond of the 40MHz causing too much interference, try moving it to channel 1 or switch to default 20MHz mode. Not sure as to why the BB wifi wouldn't work, what WPA2 you using or does it support TKIP or AES? I hear iPhones like the router's beacon period setting of 75 also RTS Threshold to be 2304, and the Fragmentation Threshold to be 2304. Have read that the BB9700 doesn't like wireless N routers, if it's not working with mixed mode(B + G + N) then try using just B + G mode, and the BB is hinky about radio interference maybe just turning off the 40MHz channel bond could solve it.

 

[kaon]

It could be the channel bond of the 40MHz causing too much interference, try moving it to channel 1 or switch to default 20MHz mode. Not sure as to why the BB wifi wouldn't work, what WPA2 you using or does it support TKIP or AES? I hear iPhones like the router's beacon period setting of 75 also RTS Threshold to be 2304, and the Fragmentation Threshold to be 2304. Have read that the BB9700 doesn't like wireless N routers, if it's not working with mixed mode(B + G + N) then try using just B + G mode, and the BB is hinky about radio interference maybe just turning off the 40MHz channel bond could solve it.

OK, I've changed the downstairs router to CH1, 20MHz width.
No difference.
Have not tried the beacon interval and thresholds yet, since I can see that the 100ms and 2346/2347 settings are already working in the downstairs router, and the same settings are in the upstairs router.

 

[overdrive31]

I would suggest running 20MHz channel width for stability sake, 40MHz just causes problems. The BB9700 is the only problem left? Does it work with the router but not the AP? How are you entering the WPA2 passphrase, with WPS or manual? Many have suggested manual WPA2 entry is the only way to go with the BB9700. Tried assigning a static IP either with manual setting or DHCP reserve? Oh, and using the same passphase for multiple SSIDs won't harm anything. Sorry, forgot you had asked.

 

[kaon]

I would suggest running 20MHz channel width for stability sake, 40MHz just causes problems.

done. back to 20MHz width now. CH1 downstairs, and CH11 upstairs.

The BB9700 is the only problem left?

At the moment, yes. But for the last few months, laptops in the position of PC05 would intermittently loose the ability to get connected, even though the signal was strong, and sometimes required reboot of the upstairs router.

Does it work with the router but not the AP?

yes.

How are you entering the WPA2 passphrase, with WPS or manual? Many have suggested manual WPA2 entry is the only way to go with the BB9700.

always manually.

Tried assigning a static IP either with manual setting or DHCP reserve?

Have not tried this. If I am not wrong, DHCP reservation would be done at the downstairs router, right?

Oh, and using the same passphase for multiple SSIDs won't harm anything. Sorry, forgot you had asked.

OK. Thx.

 

[thiggins]

Sounds like the WRT54GX might be flaky / failing. I'd try an experiment using it as a router again and see if the same clients have problems connecting. Or at least reset it to defaults and set it up again as an AP, to make sure that wireless default settings are in use.

As overdrive suggested, stick with 20 MHz bandwidth, use Channels 1 and 11. Different SSIDs are ok. Don't futz with any of the advanced wireless parameters (beacon, etc.)

In the client(s) that are having trouble connecting, try deleting all the old profiles so that the client has to grab all new connection info.

 

[overdrive31]

Have not tried this. If I am not wrong, DHCP reservation would be done at the downstairs router, right?

Correct.

I have an sneaking suspicion it's related to how WPA2 is setup, not properly using the intended protocol(TKIP or AES). I don't have an WRT54GX nor a BB9700 to see if you are able to specify exactly which, I know from researching that the BB doesn't seem to allow a specific protocol selection. So it must be up to the AP's setting, could it be the WPA2 setting is set to auto? If it can be chosen, choose AES only not either or.

P.S. Try disabling the 1st floor router's WiFi while trying to get the 2nd floor's wireless to work, so the associated profiles if any, don't hinder your progress getting wireless to work there.

 

[kaon]

Yes, I have set CH1 downstairs and CH11 upstairs, no channel bonding, no changing the beacon and threshold settings, still the default "100ms, 2346,2347" on both APs.

I now have 2 devices (a BB9700 and a Win7 laptop) that both are fine getting to the internet thru the DDWRT main router.
Both are also able to authenticate with the (upstairs) WRT54GX, and are able to ping the main router 192.168.1.1 (sometimes intermittent), and are able to even view the ddwrt web config pages, via the WRT54GX.

BUT! they cannot ping 8.8.8.8 and can't seem to get out to the internet at all, when connected via the WRT54GX.
It doesn't seem to be a SNR issue, since I can bring the devices well within range.

InSSIDer site survey screenshot and ping details are posted in my other thread here.

 

[overdrive31]

Yes, I have set CH1 downstairs and CH11 upstairs, no channel bonding, no changing the beacon and threshold settings, still the default "100ms, 2346,2347" on both APs.

I now have 2 devices (a BB9700 and a Win7 laptop) that both are fine getting to the internet thru the DDWRT main router.
Both are also able to authenticate with the (upstairs) WRT54GX, and are able to ping the main router 192.168.1.1 (sometimes intermittent), and are able to even view the ddwrt web config pages, via the WRT54GX.

BUT! they cannot ping 8.8.8.8 and can't seem to get out to the internet at all, when connected via the WRT54GX.
It doesn't seem to be a SNR issue, since I can bring the devices well within range.

Now that says alot, I now second Tim's thought of a flaky WRT54GX, and here I thought we had just the BlackBerry to worry about.

 

[kaon]

So PC04 doesn't have an issue with DHCP?

Just verified this.
A laptop that has problems when wirelessly connected thru the 54GX, when instead connected with a CAT5 to the 54GX, does get DHCP from the main router, and reaches the internet normally, as if the 54GX is a normal plain switch.

 

[kaon]

This is the output when pinging from the Blackberry9700 connected to the 54GX

Ping to 8.8.8.8 [8.8.8.8]
Ping #1: Ping request timeout
Ping #2: Ping returned after 2040 ms. Success!
Ping #3: Ping request timeout
Ping #4: Ping returned after 91 ms. Success!
Ping #5: Ping request timeout
Ping #6: Ping returned after 72 ms. Success!
Ping #7: Ping request timeout
Ping #8: Ping returned after 95 ms. Success!
Ping #9: Ping request timeout
Ping #10: Ping returned after 49 ms. Success!
Ping statistics for 8.8.8.8: Pings Sent: 10, Pings Received: 5
, Min time: 49, Max time: 2040, Average: 469

Ping to 8.8.8.8 [8.8.8.8]
Ping #1: Ping request timeout
Ping #2: Ping request timeout
Ping #3: Ping request timeout
Ping #4: Ping request timeout
Ping #5: Ping request timeout
Ping #6: Ping returned after 34 ms. Success!
Ping #7: Ping request timeout
Ping #8: Ping request timeout
Ping #9: Ping returned after 179 ms. Success!
Ping #10: Ping request timeout
Ping statistics for 8.8.8.8: Pings Sent: 10, Pings Received: 2
, Min time: 34, Max time: 179, Average: 106

Although, often times, it's 0% success over 10 tries.
Really confounding.
I really hope that the problem is only within the WRT54GX.

Because this is the second router that I have placed in that position.
The first was a D-Link DGL-4300, and it also seemed to be flakey, only good for a few days after a factory reset and reconfiguration. Then it goes intermittent, where some machines sort of get a half-good connection.

 

[overdrive31]

There are updated releases of the NEWD2 builds of DDWRT for which you could be experiencing a bug...

 

[kaon]

A related question - on deploying wireless routers without using their "routing bit"

What should be filled in for the setting indicated in the attached screenshot?

Since we are not using the WAN port, one might think that it doesn't matter.
Would be nice if these firmwares had a "AP mode" for us to select... but what would you choose in this case?

I have always left it at the default Auto-DHCP. Of course the DHCP server should be disabled.

 

[overdrive31]

The WAN port setting doesn't matter correct.

 

[kaon]

There are updated releases of the NEWD2 builds of DDWRT for which you could be experiencing a bug...

Updated it to DD-WRT v24-sp2 (08/07/10) mega - build 14896
Did flash without reset method, thinking I could save on reconfiguring, but the resultant router was a bit wonky, some clients could connect, and others only half-connect. And saw some fields in the newly updated dd-wrt were fillled wrongly, like settings from a different field was moved into a wrong field.
So I did factory-restore, then reconfigure.
Things are back as before, the problem with wireless clients coming thru from the 54GX remained the same.

 

[kaon]

In case it wasn't apparent, my intention is for all desktops, laptops, smartphones in the household to get DHCP from the main (ddwrt) downstairs router.
Such that all of them get IPs in the same subnet, 192.168.1.X
Hope this is OK?

I ask because I was thrown off when reading this guide on "client bridge mode".

I don't really know the reason why one would want to have a different subnet on the secondary AP.

 

[kaon]

Routing table?

Does this look OK?
There is only one entry in the routing table.
I just disabled the NAT... if that matters at all.
Not much difference.

 

[overdrive31]

NAT disable wouldn't have made any difference. The routing table looks fine. Are you absolutely certain your clients are linked to the WRT54GX when the packet loss is occuring? If they are in range of the 1st floor router they could be using it's preferred profile with a really weak signal causing the packet loss. Try turning the 1st floor wireless off and do your testing. Setup static IPs and forget about DHCP except for ethernet only devices.

The MIMO features of the WRT54GX called SRX were like Pre-N technology, maybe the clients don't agree with it, is there a setting to turn it off? I have found a suggestion for turning off UPnP on Linksys routers when using them as APs, give it a go.

The Intel wireless cards are notorious for drivers that seem to default to G only or N only(2.4) even though they support A, B, G, and N(2.4 and 5GHz), look into the driver settings and make sure features are not turned off. Intel's wireless utility drives me nuts(profile corruptions, buggy) even after several generations of updates, try using windows wireless utility.

Ignore that client mode setup the firmware is so old, DDWRT does a client mode wireless to ethernet bridge using same subnet pretty simply, but client mode only allows wired hosts to connect to it. If you want to have it also serve wireless, you must use it as an repeater bridge cutting bandwidth in half for wireless devices connecting to it. You have run CAT5 so no need for wireless client/repeaters, just leave it be.