Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Author Topic: Adding 2nd WAP - Having difficulties  (Read 3984 times)

risk_reversal

  • Reg Member
  • ***
  • Posts: 181
Adding 2nd WAP - Having difficulties
« on: January 31, 2009, 12:26:36 PM »

I am trying to add another WAP to my existing set up and am having some difficulties.

My current set is as follows and working without issues

1. ST585 v6 which I am using as an adsl modem / router ie wireless disabled
2. DG834G v2 which I am using as a WAP ie DHCP / NAT disabled

I do have a PAP2 and a hardwired pc also connected to the ST585 v6. I make all config changes to router, WAP(s), etc by hardwired pc only.

The IP address is as follows
1. ST585 v6 gateway 192.168.0.1
2. ST585 v6 DHCP IP range 192.168.0.2-64
3. DG834G v2 Fixed IP address 192.168.0.100

I inherited another DG834G v2 and wanted to use it also purely as a WAP but connecting it has proved difficult for some reason.

The new DG834G v2 is set up in a similar fashion to the existing one ie fixed IP address 192.168.0.101 and with DHCP / NAT disabled. It also has the same firmware 2.10.17.

The WAPs were set up with different SSIDs and on separate channels 3 & 11 (I did not want to create a roaming setup just move some wireless clients from a congested WAP).

The 2 WAPs are connected into separate ports on the ST585v6 and are connected using straight through cables.

The problem with the second wap is as follows: When I fired up a wireless client pc, it would not connect, even if I manually created a profile. Also, when searching for new networks, It could not find the wireless network at all. I also made sure that I was on the right channel (11 was new one). I did try to ping the new wap from the wireless client with limited success. Prior to attempting to connect, the ping was successful but after an attempt to connect was made, then the ping would fail. More intrigingly, when carrying out any changes in the second WAP for some reason it would at times reboot and revert back to its factory default setting ie DHCP enabled and IP address 192.168.0.1.

What I then did:
Now in the first instance, I though that the 2nd DG834G v2 had some form of HW failure. So I made a copy of the settings of the original DG834G v2 which I restored to the inherited DG834G v2 and then substituted the original DG834G v2 with the inherited one.

Once substituted, the new DG834G v2 was found to be working fine with the wireless clients. Exactly the same as with the original one. 

Intriged by this finding, I then set about as follows
I have a backup router all set up and ready to go just in case. It's a DG834 v2 (non-wireless). So I substituted the ST585 v6 with the DG834 v2 reconnected everything and the same thing as above happened ie no wireless detection by client and the DG834G v2 would reboot to default configuration after certain changes were made.......

Puzzled. I know I am

Questions

1. In the first instance is there any reason why a second WAP should prove problematic. I have searched on the net and can see no evidence that it shoud not work.
2. Stupid question but can I connect a second WAP this way or have I missed a vital step somewhere.
3. I am connecting with straight through cables, is this correct?
4. Obviously, something is happening when 2nd wap is being added so should I be using a bridge/switch (not sure how they operate but was reading about this on the net)

Anyone have any ideas about this, if so, these would be much appreciated.

Sorry about long post

Cheers
« Last Edit: January 31, 2009, 12:37:35 PM by risk_reversal »
Logged

Weaver

  • Addicted Kitizen
  • *****
  • Posts: 7782
  • Retd sw dev; A&A; 4 7km ADSL2; IPv6; Firebrick
Re: Adding 2nd WAP - Having difficulties
« Reply #1 on: January 31, 2009, 01:27:22 PM »

I'll ask a stupid question or two of my own (apologies if you've already answered any)

What is the ST's opinion on the netmask it is using for the LAN? ( Answer, presumably the usual 8 bits wide if its a typical SOHO ISP with NAT added on)?

You said that you set the LAN-facing IP address of the 2 DG834Gs to 192.168.0.100 and 101 -?

From a wired device straight into the ST first :-

What happens if you try to ping the various devices in turn and then execute the command
      arp -a ?

What do the routing tables look like in the three routers?

> Should I be using a bridge or a switch

Well the answer to that is certainly "yes", but on reflection I'm not entirely sure off hand why what you've shouldn't work, as you say that you got one to work which I found surprising (but mainly because I hadn't given it enough thought just showing my stupidity), and so getting one to work is a miracle achieved.

The normal thing to do :-) would be to get a "proper" wireless access point such as the Netgear WN802T or even better its newer 5GHz sibling. Older 802.11g kit such as the Linksys WAP54G is an old favourite too. These devices are wired-LAN-to-wireless LAN bridges. A bridge simply copies everything from the LAN side to the WLAN side and vice versa. If it's "dumb" that is, a smart or "learning" bridge discovers where things live, remembers it and then copies things intelligently in future. Just as a smart wired switch does, which learns which cable a device lives on and copies packets to the right cable from then on rather than broadcasting packets down all the cables as it has to initially before it knows where anything is.

But having said that, I'm not at all clear why it shouldn't work. A wireless router has to act as a bridge anyway as it has to copy things between its wired LAN ports and wireless anyway.

One thing I have noticed is that if some SOHO routers discover that a particular MAC address is accessible via more than one port on its switch then it freaks out. Which is a bug. I saw this with my Netgear DG834G recently when I plugged two network cables into it which both lead to the same device. I don't see how you could have done the same thing or its equivalent, but it makes me wonder if there are other bugs around relating to things such as MAC address to port mapping or ARP tables which might be a good way of killing the netgears.
« Last Edit: January 31, 2009, 02:03:01 PM by Weaver »
Logged

risk_reversal

  • Reg Member
  • ***
  • Posts: 181
Re: Adding 2nd WAP - Having difficulties
« Reply #2 on: January 31, 2009, 01:55:35 PM »

Quote
What did you set the LAN-facing IP address of the 2 DG834Gs to? (One was originally 192.168.0.1)

The main router ST585 v6 (and the back up router DG834) has/have 192.168.0.1 (gateway), DHCP IP range 192.168.0.2-64

The original WAP fixed IP 192.168.0.100
The new WAP fixed IP address 192.168.0.101

Quote
What happens if you try to ping the various devices in turn and then execute the command arp -a ?

I will do that later as my children are on the net now and if they loose connection they will start shouting ...again!!!!

Cheers
Logged

risk_reversal

  • Reg Member
  • ***
  • Posts: 181
Re: Adding 2nd WAP - Having difficulties
« Reply #3 on: February 01, 2009, 05:00:20 PM »

Quote
One thing I have noticed is that if some SOHO routers discover that a particular MAC address is accessible via more than one port on its switch then it freaks out. Which is a bug. I saw this with my Netgear DG834G recently when I plugged two network cables into it which both lead to the same device. I don't see how you could have done the same thing or its equivalent, but it makes me wonder if there are other bugs around relating to things such as MAC address to port mapping or ARP tables which might be a good way of killing the netgears.

I have managed to get the new DG834G v2 working. It would appear that your comments above regarding bugs in this type of unit may have been correct.

The reason I say this is as follows. I previously stated that the new DG834G v2 would reset itself to factory default after a number of configuration changes were made. Well, the first unit seems to do that as well even when it is the only one connected. I am not sure why this is the case but maybe poor engineering as you said.

However, in the event that it may be of use to others this is what I did.

I configured the new DG834G v2 on a separate pc (this is required in any case to change the IP address and disable DHCP). However, in this case I configured it totally to include SSID, channel, encryption, mac addressing, etc....so the unit was ready to go and would need no changes.

I then reconnected it and it seemed to work although at first, I did have issues with channel 11 which did not seem to play ball. However changing to channel 10 seems to cure this (at least with the one wireless client that I have tested).

I can ping the new access point from another wireless client that is not on that wireless network and the routing tables (arp -a) from same pc also all look fine.

Obviously, although using the DG834G purely as a wap can be done, I would suggest to others that are considering doing this to maybe look to another manufacturer or to a unit that is better specced.

Many thanks

Cheers
« Last Edit: February 01, 2009, 05:04:08 PM by risk_reversal »
Logged

Weaver

  • Addicted Kitizen
  • *****
  • Posts: 7782
  • Retd sw dev; A&A; 4 7km ADSL2; IPv6; Firebrick
Re: Adding 2nd WAP - Having difficulties
« Reply #4 on: February 02, 2009, 06:14:31 PM »

You definitely deserve an award for research for the good of science, and it would be worth an email to Netgear so that they can put this into their testing matrix for future releases, as from experience behind such a bug there is likely some underlying badness that could have wider consequences.

Seriously though folks, the Netgear WN802T doesn't cost the earth, is a snip to configure in terms of IP as there is no routing, and has a gigabit NIC

btw: I notice that said I had a DG834G back there, I don't, I meant DG834 - just finger trouble.
Logged
 

anything