DHCP issueing same IP

I have a very small home network that is configured as:
- DirecWay 7000 modem feeding an Airport Express
- A 8 port switch connected to the Airport Express
-- A PC, 2 Printers connected to the switch
- A G5 iMac conneccted to the Airport Base with WEP on
- A Airport Extreme connecting with WDS and also allow wireless clients checked.
- A PC connected to the Airport Extreme with WEP on
- Guest laptops connecting wireless
The Aiport Express is issuing IP addresses in the 192.168.0.x range and it is set to distribute IP addresses and share a single IP address.
The issue is I brought 2 laptops from work and a friend stopped by with a laptop and when we connected the same IP was issued several times. I checked the lease period and it was 24 hours and the computers that had the original IP had not gone past that time. If I used ipconfig to release and renew the connection it would sometimes clear it. I did not have an issue with the two Mac's just the windows systems but that could have been chance. Does anyone have an idea what the cause might be.
Thanks in advance
G5 Mac OS X (10.4.8)

- DirecWay 7000 modem feeding an Airport Express
- A 8 port switch connected to the Airport Express
As the AirPort Express Base Station (AX) only has one Ethernet port, how did you manage to get both the modem & 8-port switch connected? ...unless you mean that this is an AirPort Extreme Base Station (AEBS) instead?
- A Airport Extreme connecting with WDS and also allow wireless clients checked.
So, this AEBS is acting as a Remote Base Station, with the AX acting as the Main Base Station in the WDS setup...correct?

Similar Messages

Wierd DHCP Issue

Hello All,
I facing a very wierd DHCP issue and would like to know your thoughts on it.
I have my wired clients on vlan 1 and wireless cleints(eap-peap) on VLAN 2.
We are facing an issue where multiple wired clients who were on access port vlan 1 are receiving IP address from wireless subnet(vlan2) -their DHCP server was the WLC virtual gateway IP address(1.1.1.1). This is causing an outage to few wired clients.
The WLC trunk does not have vlan 1 allowed on its ports and all APs are in local mode and all on access vlan.
I'm not entirely sure whats causing this, but only way I think this is possible is that 'A Client' laptop has his network connections bridged - his wired nic on VLAN 1 and wireless NIC on vlan 2, acting like a WGB, which is causing new wired clients(vlan1) DHCP broadcast request forwared through the bidge mode laptop to AP--> WLC. Do you think this is possible??
Havent been able to identify which client is causing this issue yet.
Has anyone faced a similar issue and anyway to block this through WLC/ACS policy?
Thanks
Jino

Hi,
Might we consider to make use of network monitor to take a look at the traffics for the 1.1.1.1 address?
How to use Network Monitor to capture network traffic
Download link here:
Microsoft Network Monitor 3.4
Best regards
Michael Shao
TechNet Community Support

Very weird dhcp issue

We've started 're-vlanning' our main location here, breaking up depts
into their own vlans.
All seems ok so far, aside from a real doozy.
For the IT vlan, we have one address that will not talk to our web
content mgmt appliance. It's the 2nd address in our assignable pool,
and it doesn't matter if it's dhcp or statically assigned, that address
will not talk to that device.
That is the *only* device that cannot be reached from this particular
address in our dept vlan, every other one works fine.
Any ideas on this?
Stevo

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
> and it doesn't matter if it's dhcp or statically assigned, that
> address
So.... the title of this thread should actually be 'Very weird non-DHCP
issue', since your own testing confirms this has nothing to do with DHCP?
If you do a LAN trace on this machine as well as your web content
management appliance do you see packets on either side? Both sides? If
not on both sides but you do on the source (workstation) side see
packets going out, then get LAN traces after each network device
(switch, router, firewall, etc.) to see when the packets disappear.
Feel free to post the LAN traces somewhere with descriptions of IPs,
ports, and what you should be seeing, if you want to post them somewhere
for review.
Good luck.
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Version: GnuPG v2.0.18 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
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NZ/liqfCgjyIcykWWeKGgdtm2I7JZOcFiG8YW2le55mcltvCL1VJW +1VGng4kZER
0f4hjfyQ3CcQ6HIU3RM6VL5U2Pblb80MsEQe0qo0xgtPXipmjs i7Q0xIv9p0wT7A
7JMkfgM9tfuI5Yro+BDLfSIkFWicKuKs1sKpNugKalPuyyRrzW IiznoalIKFshon
a40ETLJVZmngBYfqfeZL9nPNsFlveFNXrDkdbl2WbaprsHtNnA NwZfVUIlc5kOCT
MknY0GXof4/tk149OVCCLgjEzoRtTIZH0BJTHQwW7ANkWUUNYwi49+Mk46V0o awl
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j8fezki9PMznkcT+of2Oe4T99K9fChN2WFSgUKdlpkYSjbkmjP fdbWloou+WBjCm
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6500 DHCP ISSUE

Hello All,
I am having an issue do DHCP from the 6500, and was hoping someone cant help. So, I tried to setup DHCP from the FWSM to the clients and this worked fine with giving out the IP, however the gateway for devices on the inside is supposed to be the 6500, not the FWSM, which is why the clinets wouldn't get out to the internet. Do I need to set up DHCP relay on the FWSM or does anyone know the way I can setup DHCP on the 6500 to give out IP's to the clients. Again just to reiterate, when I setup DHCP on the FWSM the clinets get the IP's but do not get out to the internet and when I setup DHCP on the 6500 the clients do not get an IP. Also I know tghis is a dhcp issue becasue when I assign a static address on the network the clients get out fine. Thanks in advance for the help!
6500 Config
ip dhcp pool TEST
   network 1.1.1.0 255.255.255.0
   default-router 1.1.1.1
   dns-server x.x.x.x y.y.y.y
FWSM Config
FWSM/TEST# show run
interface Vlan3
nameif outside9
bridge-group 1
security-level 0
interface Vlan203
nameif inside9
bridge-group 1
security-level 100
interface BVI1
ip address 1.1.1.4 255.255.255.0
passwd 2KFQnbNIdI.2KYOU encrypted
access-list INSIDE1_IN extended permit ip any any
global (outside1) 1 x.x.x.x
nat (inside1) 1 1.1.1.0 255.255.255.0
access-group INSIDE1_IN in interface inside1
route outside1 0.0.0.0 0.0.0.0 1.1.1.1 1
FWSM/TEST#

Hello Alain,
Thanks for your quick response. I attached a Diagram of the layout. Just to let you know this is an FWSM with many virtual contexts and most including this one that are Transparent. I understand that I need an access-list on both ends to specifiy so the FWSM opens it, I am just having issue because the FWSM sees this as unsual traffic and the access-list needs to be on-point to work. Thank you for the response and I'll look forward to hearing back from you.

VRF and DHCP issue

VRF and DHCP issue
We have a 6500 ( 12.2 (33) SXH5 ) that has a VRF running for our guest network. On this 6500 resides the DHCP pool with a range defined for our guest network. We have a stack of 3750's (12.2 (46) SE) connected to the 6500 with a L3 connection. The 3750's have a local guest VLAN with its gateway defined in a VLAN interface. This VLAN on the 3750 has an IP helper address pointing to an IP within the VRF on the 6500. When debugging DHCP on the 6500, a request is received and sent back out. The client never receives this request.
If a static IP is applied, the client is able to communicate anywhere within the VRF successfully (including pinging the IP within the helper-address. As many posts have pointed out - there is no VRF <name> under the ip dhcp pool <name> within the 6500. I am just wondering if anyone else has run into this and what their solution was.
Thanks.

Hi,
I have tested the dhcp server and vrf on Cisco 3640 and it is working without VRF under the ip dhcp pool. Please ensure that you have configured routing for the dhcp-relay agent(VLAN facing dhcp client on 3750 in your case).

DNS / DHCP Issues in Server 2008R2 Domain

Hi folks,
We’ve been having an ongoing issue for a while now in that some PCs and laptops (Win 7) in our company can’t be contacted by hostname i.e. if we try and RDP from one Windows 7 PC to another the RDP session fails as if the PC isn’t turned on, but it
is indeed turned on and connected to the network.
Even if we ping the host name of a particular computer that is on it fails to reply but if I go into DHCP I can find the hostname bit it has a different IP address assigned to it other than what is listed in DNS for that host name.
So for some reason when some computers get switched on and be allocated a new dynamic IP address through DHCP the corresponding record in DNS doesn’t seem to get updated meaning we need to go into DNS and manually amend the Host A record with the new
IP address that it has been given so we can RDP onto that computer using the hostname.
At present aging and scavenging isn’t enabled in our environment as we are afraid to in case it removes live DNS entries that just haven’t been turned on in a wee while. Does aging and scavenging just ignore static DNS entires and does aging and
scavenging work in DHCP as well?
One other thing I noticed is that if I delete an incorrect DNS Host A record and create it manually and assign the hostname and the correct IP address it says static rather than having a timestamp on it. When I create the new record I always click on our
domain in the Forward Lookup Zone and on creation I always select Create the associated pointer (PTR) record so not sure why the manual record doesn’t get a time stand.
So any help/advice or suggestions would be greatly appreciated.
Thanks,
Bonemister

Hi David,
Thanks for your reply and for clarifying those things for me. Unfortunately in my workplace when I add a manual DNS Host A record it does become a static entry and doesn't have the '0'
you mention, do you have any idea why that would be as I'm worried about it affecting things if I were to enable aging and scavenging.
Is it possible to just enable aging and have it remove entries before a time of my choosing or does scavenging need to be enabled also?
I still can't understand why the relationship between DHCP and DNS isn't working correctly. Sure if DNS has an A record for a computer and the IP address changes via DHCP there is bound to be
a way to setup DNS to be able to update the records it holds - do you know if my reading of this is correct.
By the way, I can confirm that my adapters TCP/IP DNS settings are the same on of the PCs that had the DNS fault as in your screenshot the only different is we have the tick in Append parent suffixes... - would that make a difference.
Thanks also for that other link, it seems very interesting and I'll have a good read through it carefully before doing anything!!
Thanks again for you reply and I look forward to seeing any responses.
Regards,
Bonemister

2100 wireless LAN controller intermittant DHCP issue does not respond to clients

Hi everyone,
I have been struggling with a difficult problem for some time now:
The cisco 2100 wlan controller I have is configured with a dhcp scope in the same ip address range as its WLAN. The configuration works and on a good day I have up to 200 clients connecting with out issue. In the web interface they display as associated and authenticated
On a bad day I find I will begin seeing about 50-80% of all new devices that attempt to join the WLAN show up as associated but not authenticated. These clients end up self assigning themselves a 169.254.0.0/16 (APIPA) address
When my controller / WLAN enters into this state: if clients leave the WLAN they typically fail to get back on and successfully authenticate. By the end of a day around 80-90% of all devices are essentially without Internet access due to this issue.
Rebooting the controller and or APs typically makes no difference or makes things worse – although sometimes it appears to resolve the issue. The same holds for disabling the entire wlan for about 10 minutes and then re enabling it.
Im using 1130 cisco aironet APs with the controller. I have checked extensively for interference and congestion – I think I have congestion – some APs typically host 40 to 90 devices. However as mentioned on a good day the wlan will host 200 devices all day without any issue and some APs will host 50 to 70 devices without major issue.
I can provide more specifics if anyone should need – eg firmware, IP addresses, exact model numbers etc.
Please let me know if anyone has seen something like this before ?
I believe the 2100 is rated to handle up to 350 devices and its recommended not to load a 1130 AP with more than 25 devices ??
Regards
Matthew

Hi Amijad, Hi George:
Thank you both for your time in considering my situation.
I will think about implementing an independant DHCP server; im really wondering if the equipment is just overloaded
- What software versoin the WLC uses?
Product Version.................................. 6.0.199.4
RTOS Version..................................... 6.0.199.4
Bootloader Version............................... 4.0.191.0
Emergency Image Version.......................... 6.0.199.4
PID: AIR-WLC2106-K9, VID: V05
- What ports of the WLC are connected to the neighbor swtich? one or more?
2 ports connect to the neighbor switch on separate vlans
- port 1 is vlan 0 and hosts the management and ap-management IPs for the wlan controller
- port 2 is vlan 1 and hosts the wlan
- the controller has one dhcp scope defined on port 2 for the WLAN
- What is the security of your WLAN?
WPA+WPA2
AES
PSK
- Do you have "DHCP required" enabled on the WLAN?
yes DHCP required is enabled in the WLAN
please let me know if you have any additional advice.
regards
Matthew

DHCP issues on wireless

When I connect to my wireless router (D-Link WBR-2310 I believe) using my mac, it gets the default self-assigned address instead of DHCP-assigned address. My PC connects fine wirelessly and wired over ethernet. If the router is reset, it works fine. If I assign manual address to iBook wireless, it works fine (by "works fine" I mean that I can connect to the internet).
Had similar problem with my old Linksys router (Linksys WRT54G) where the following devices had issues connecting to the internet iPod Touch, iBook, PowerBook, and MacBook. This was under unsecured, WEP and WPA settings.It seems that the issue is resurfacing with my current router.
Currently, I am using WPA security (I don't like WEP and neither does my PC). I would rather not switch security settings to unsecured due to the close proximity of my neighbours (yes it's canadian spelling!).
Any suggestions?

I have encountered this same router and issue visiting my future in-laws for the holidays. DHCP with manual address appears to work, but I also still encounter occasional drops. The router is setup for WPA2 security, and support a mix of Mac and Win clients. I haven't put a lot of time into trying to fix it, but here is what I know so far:
1) Sometimes it does just work with DHCP
2) DHCP with manual address works, but will still drop occasionally for brief periods
3) Sometimes, just turning the airport off then on again will resolve the issue and pull an address
4) Just waiting about 30-60 seconds also seems to work -- usually
5) Plugging into the wire works great!
I haven't sat by the router and worked on this, but it seems that occasionally the router just drops the signal, and with it the DHCP assignments. Something about the DHCP implementation is very slow, and it just take a while to get around to assigning an address to my machine. I haven't looked into firmware updates since it's not my box and I don't want to mess it up further and then leave, but that's certainly something to check into.
We also have an 12" PB that cannot even connect to the wireless with the "Error joining wireless network" message. Haven't been able to figure that one out at all.
They may just be getting an Airport or Linksys as a late x-mas gift here... (as my connection drops again while I type this! Airport off, airport on, wait 30 sec, and we're back)
Cheers, and good luck!

Using X3500 as a Wireless Extender DHCP issue iPhone 6

Hi
Hopefully a simple question with a simple answer.
Background:
I've transitioned away from my ADSL ISP to a cable provider (VirginMedia). My new ISP comes with a cable modem (SuperHub 2 ac) and I've connected the two devices together to extend my home wireless network. The cable modem is The two routers are physically remote from each other - connected via just their Ethernet ports - via power-line technology (Devolo dLAN 1200+). The two routers have the same broadcast SSID albeit on separate channels.
Issue:
All devices in my house, laptops tablets, phones roam between the two wi-fi zones seamlessly *except* the iPhone 6 (iOS8.1), this works on the cable modem wi-fi - but not on the X3500 wi-fi. I also have an iPad Mini 2 (also iOS8.1) which also works - so rightly / wrongly I've ruled out iO8.1 as the issue. Oddly the iPhone 6 connects to the x3500 but doesn't obtain an IP address (the cable modem is the DHCP server). Even setting a static IP address doesn't help.
Observation(s):
If the X3500 is setup as a DHCP server, the iPhoen connects (and gets an IP address), but then the default gateway is incorrect (gatway is the IP address of the X3500 not the remote cable modem). I can't find anywhere to specify a default gateway in the setup.
Question
I'm beginning to think this is an issue with the iPhone 6 (knowing all other devices work correctly), but I just want to make sure I'm configuring the X3500 correctly. I'm specifically interested in the whether I'm using the right "Mode"ADSL / Ethernet. I've tried "Bridged Mode Only" (ADSL) and "Automatic DCHP Only" (Ethernet) but neither seem to resolve the issue that the iPhone 6 is having.
any suggestions on how to resolve / troubleshoot would be most welcomed.
Thanks!
Solved!
Go to Solution.

Yes, there's a way for you to override the IP Address. It is on Router Address under Network Setup on the Basic Setup tab. If I'm not mistaken, one end of the Ethernet cable should be connected to the regular Ethernet port of the cable modem and the other end to the cable port of the X3500.
But if it's just the iPhone that won't connect to the X3500, it might be okay to retain the current configuration of the router, but try adjusting the wireless security mode or set the wireless channel to 11 and observe what happens.

Vwlc 7.3.101.0 DHCP issue ?

Hello all,
a wireless client can't get an IP address via DHCP.
The controler is configured as "DHCP bridging mode", the DHCP server is a 3750 on the same L2 segment.
The security part is done by ISE 1.1.3, the client get authenticated successfully and debug on the vwlc says :
(Cisco Controller) >*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP received op BOOTREQUEST (1) (len 308,vlan 0, port 1, encap 0xec03)
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP processing DHCP REQUEST (3)
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP   op: BOOTREQUEST, htype: Ethernet, hlen: 6, hops: 0
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP   xid: 0x7f6910ce (2137592014), secs: 0, flags: 0
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP   chaddr: 00:26:4a:fd:ed:a4
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP   ciaddr: 0.0.0.0, yiaddr: 0.0.0.0
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP   siaddr: 0.0.0.0, giaddr: 0.0.0.0
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP   requested ip: 192.168.10.4
*DHCP Socket Task: Apr 22 17:50:13.445: 00:26:4a:fd:ed:a4 DHCP successfully bridged packet to DS
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP received op BOOTREPLY (2) (len 308,vlan 0, port 1, encap 0xec00)
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP processing DHCP ACK (5)
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP   op: BOOTREPLY, htype: Ethernet, hlen: 6, hops: 0
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP   xid: 0x7f6910ce (2137592014), secs: 0, flags: 80
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP   chaddr: 00:26:4a:fd:ed:a4
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP   ciaddr: 0.0.0.0, yiaddr: 192.168.10.4
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP   siaddr: 0.0.0.0, giaddr: 0.0.0.0
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP   server id: 192.168.10.1 rcvd server id: 192.168.10.1
*DHCP Socket Task: Apr 22 17:50:13.447: 00:26:4a:fd:ed:a4 DHCP successfully bridged packet to STA
however, the wireless client never get the IP address.
See attached .jpg, the IP address seems to be attached to the wireless client.....
Is anyone could help me please ?
Regards.
TM

Ok DHCP Snooping was the issue....
The DHCP message response seems to enter back the switch (from the vwlc to the AP ) on the same port it came from.
(the Sw acts as a DHCP server)
Now I have an IP address assign by DHCP but no connectivity though !!!

Wireless dhcp issue after upgrading WLC to 7.6.100

Hi All,
We have upgraded our controllers to version 7.6.100. After upgrading, the access points also upgraded their version to 15.2(4)JB3. But, the problem is that after this process the APs do not get IP. It stays on this state:
*Sep 26 03:55:36.334: %CAPWAP-3-DHCP_RENEW: Could not discover WLC using DHCP IP. Renewing DHCP IP.
Not in Bound state.
The DCHP configuration is OK, since it is working in other two controllers we have and that we are not upgrading untill this issue is solved.
If we connect the APs via console and configure a static IP and controller's IP, the AP registers and works fine. But, the access points are located in 20 remote sites, so we would like to avoid going site by site.
Has anyone suffered this issue and knows how to "recover" those access points?
Thank you very mucho for your help!

Hi,
Thank you for your answer conraddaniel.
But, our issue was an error on the DHCP. The DHCP server pool for the APs was configured with lease time infinite (on a Cisco 6500). After capturing the packets and debugging on the AP we realized that the AP were receiving wrong values:
DHCP: Scan: Renewal time: 2147483647
DHCP: Scan: Rebind time: 536870911
So, on the AP debugging we saw:
DHCP: Scan: Renewal time larger than Rebind time
On Cisco documentation:
T1 Timer(Renewal) After a certain portion of the lease time has expired, you attempt to contact the server that initially granted the lease in order to renew the lease so its IP address can still be used.
T2 Timer(Rebinding) If renewal with the original leasing server fails, because, for example, the server was taken offline, then you ideally try to rebind to any active DHCP server and try to extend its current lease with any server that allows it to do so.
These T1 and T2 timers can be any values, but must be less than the IP address lease duration. T1 Timer must be less than T2. Generally T1 is set to 50 percent of the lease duration and T2 is set to 87.5 percent of the lease duration. Use this rule to set T1 and T2 timers.
On the previous version of the WLC, the DHCP was configured in the same way and we confirmed that the APs received same times, but they ignored those wrong values.
The workaround was to modify the lease time of the DHCP pool (1 day). This way, both timers had valid values and the APs accepted the DHCP OFFER. We still do not know why with lease infinite these timers have wrong values (a bug?).

WAP551 DHCP issue

Hi,
I have trouble with new WAP551 accesspoints.
For supplying a new building on our campus we decided to use WAP551 accesspoints. Another building is working with WAP541 models an all is working fine.
The accesspoints are working in cluster mode with 16 nodes. They are supplying multiple SSIDs in multiple VLANs with different DHCP Servers in some VLANs.
When I start switching between the SSIDs I will not get a DHCP address. When I am going to look at the switchport, where the AP is connected, I cant see any DHCP Packet passing by. It seems that the AP stops passing DHCP. Sometimes it takes a few minutes, then suddendly a DHCP request passes by and my client gets an address.
To isolate the issue, I took one of the new WAP551 to the old building and installed it there as single AP, but it is the same there (so it has nothing to to with my infrastructure of the campus) and the WAP541 are still working fine - I can switch between the SSIDs a couple of times and always get an DHCP address.
I installed the latest firmware of 2015-01-19 - 1.1.2.3 - but no change - still the same.
I have no idea whats going on, has anybody here new ideas?

My name Eric Moyers. I am an Engineer in the Small Business Support Center.
I am sorry to hear that you are experiencing this issue.
This seems to be a very involved network. In order to more quickly troubleshoot and resolve your issue, please call our support center and open a case so that one of our engineers can work directly with you.
http://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html
Eric Moyers
.:|:.:|:. CISCO | Cisco Presales Technical Support | Wireless Subject Matter Expert
Please rate helpful Posts and Let others know when your Question has been answered.

DHCP Issue.

Hi Everyone.
I am having an issue with our LAN DHCP clients obtaining an IP from our DHCP server.
I captured some packets using wireshark while trying to obtain a IP and this is what i found.
I get the discover, offer, request and then ACK, but for some reason the PC starts the procedure over again even after ACK was received. Everything looks good withing the DHCP transaction except the PC does not keep the IP handed out to it. The ACK has a
valid IP within scope, mask, gateway and all the info is there.
Funny thing is we have wireless clients able to obtain IP's just fine. This only is a problem for our wired clients. Also the wireless DCHP process seems identical to the LAN DHCP process yet our LAN PC's keep sending out a discover even after ACK received.
I tried using a non-Domain PC and get the same result.
Any ideas? Thanks!

Is there a Linksys or some other retail-box store router that someone may have plugged in on the network that has DHCP running on the 192.168.x.x range?
Ace Fekay
MVP, MCT, MCSE 2012, MCITP EA & MCTS Windows 2008/R2, Exchange 2013, 2010 EA & 2007, MCSE & MCSA 2003/2000, MCSA Messaging 2003
Microsoft Certified Trainer
Microsoft MVP - Directory Services
Complete List of Technical Blogs: http://www.delawarecountycomputerconsulting.com/technicalblogs.php
This posting is provided AS-IS with no warranties or guarantees and confers no rights.

Unable to connect to my network (DHCP issue)

Hello,
Here is a description of my issue:
My thinkpad T43 (running on XP/SP2) has lost its connectivity to my router (Netgear WGR614) after being connected without an issue for several months. Both wireless and ethernet adapters are unable to reconnect. I also have a T60 and a HP desktop that are connected to the same router, via wireless and ethernet cable respectively.
The IPCONFIG command shows the adapters as 'media disconnected' and a "ipconfig /renew" command comes back with an error "unable to contact your dhcp server".
Following are what i have attempted with no success so far::
1. Upgraded the Thinkpad access connection utility
2. Upgraded the router firmware
3. Repaired/reinstalled the wireless adapter
4. Restarted the WirelessZero service
4. Downloaded and ran the LSPFix and WinsockFix utilities
5. Manually executed the following:
Reset TCP/IP stack to installation defaults, type: netsh int ip reset reset.log
Reset WINSOCK entries to installation defaults, type: netsh winsock reset catalog
6. Rebooted the thinkpad,router and cable modem several times in several sequence
After i reset the TCP/IP stack, the ip config has defaulted to a 169.x.x.x address. I understand that it is caused when DHCP server is not available to assign an address, but how do i get this to work?
I have even tried to force an ip address through the TCP/IP properties and manually assigned the router's ip as the default gateway and DHCP server address in the setting, to no effect. In this case, the thinkpad connects to the wireless network but does not connect to the internet.
I have looked at other threads discussing similar issue and have mostly followed their suggestions to no avail. Can someone please help me fix this issue? I will be left with only this thinkpad in a few days, so i have to get this fixed.
Your help and patience (in reading this email) is much appreciated.
Thanks.
Solved!
Go to Solution.

I tried to connect to the only unsecure network available in my vicinity, but i could not. The same issue followed.
What i notice in the result of running ipconfig is this: (In addition to the LAN and wireless adapters, i see another interface)
Tunnel adapter Teredo Tunneling Pseudo-Interface:
Connection-specific DNS Suffix .:
IP Address...................................:?
Default Gateway..........................:
I do not remember when this started showing up, but im sure this was not listed in the begining of this problem. Does anyone know the use of it or if this is causing the problem?

WVC200 DHCP issue (LAN vs Wireless

Hi All,
I have a WRT600N router from Linksys and bought a second WVC200 camera.
While setting up the first camera I had some trouble during set up (now I have the same issue with the second one).
During installation of the first camera while on the ethernet hookup as instructed the DHCP assigned a specifc IP (192.168.1.107). After succesfully finishing the initial set up I detached power and the ethernet and hooked up power alone again to switch to a wireless connection.
For whatever reason the router assigned a different IP (192.168.1.115) or so I thought....
After tinkering for a while I upgraded the Firmware to the last version and the wireless conection suddenly worked (the IP did not change).
Now to the second camera.
Did the same thing but somehow after the upgrade the IP still doesn't remain the same (despite DHCP reservation). Still falls back to the 192.168.1.115.
What I realised after checking the router is that the router doesn't recognize the wlan connection for whatever reason. I do WPA TKIP and it works just fine with the other wireless equipment. I also switched off and on the wireless MAC Filter and added the MAC address of the second camera with the right IP (192.168.1.108) in the DHCP reservation list as a device (same in the wireless filter list). I also checked the MAC address at least 10 times....
What else can I do to trick the router in finding the camera and assigning the right IP address or is the wireless connection just broken?
Thx for any help.
Malte
Message Edited by Malte on 08-18-2008 03:14 PM

I have the exact same problem! I have a WVC200 since a couple of years. It have served well but for a while ago it stopped to work properly. I didn't do anything about it right away but today I thought I should set it right.
I did a firmware upgrade, reseted the camera and started all over with the settings. At first I had a TP-cable in it. My router is a Zonet ZSR0140CP that also acts DHCPserver. I have told the DHCP that the MAC-adress of the camera should have a specific IP-adress. In the camera I have set that it should get a IP-adress from DHCP. I have a D-Link DWL-900AP+ that acts wireless AP. It is WEP Encryption with 64 bit HEX. And it doesn't act as a DHCPserver, it's just an AP
Everything went fine until I broke the electricity to the camera unplugged the TP-cable and plugged the elecricity in again.
For a long while it just serched an IP-adress and when it got one it was 192.168.1.115! Thats not much right in that ip adress... Wherever did it got that from??
Please don't tell me to reset everything. I have already done that. And I still have the same problem. I dont think it is the router/switch/AP who is the problem here.
//Camilla

DHCP issueing same IP

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