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DHCP weirdness

Discussion in 'Tomato Firmware' started by lordielordie, Mar 19, 2008.

  1. lordielordie

    lordielordie LI Guru Member

    I just added a new PC to our network and for some reason it takes 3 IP addresses... if you look at the attached image, you'll see the same mac with 3 IP addys 148,149, and 150..

    Any idea what's going on? the only thing different about this PC is that it is the only Vista PC on the network..

    [​IMG]
     
  2. roadkill

    roadkill Super Moderator Staff Member Member

    use a real operating system and try again...
    :grin:

    but I really wonder why it does that..
     
  3. sillydoh

    sillydoh LI Guru Member

    Could you describe the pc and the type of connection?
     
  4. maheath

    maheath LI Guru Member

    Since the lease times are different - maybe the PC just reconnects and gets a new IP adress assigned every time?
     
  5. TexasFlood

    TexasFlood Network Guru Member

    Could try assigning a static IP address to that MAC and see if the symptom goes away.
     
  6. kevanj

    kevanj LI Guru Member

    Are all the IPs active on the network at the same time?
     
  7. lordielordie

    lordielordie LI Guru Member

    Yes,

    those PCs are never off.. even the one wireless PC are always connected..
     
  8. lordielordie

    lordielordie LI Guru Member

    two of the instances are exactly the same time.. hummm.. that's even weirder.. how would the same MAC address get 2 different IPs, and then another one..
     
  9. lordielordie

    lordielordie LI Guru Member


    here is what an IPCONFIG looks like:


    Windows IP Configuration
    Host Name . . . . . . . . . . . . : tabor
    Primary Dns Suffix . . . . . . . :
    Node Type . . . . . . . . . . . . : Hybrid
    IP Routing Enabled. . . . . . . . : Yes
    WINS Proxy Enabled. . . . . . . . : No

    Ethernet adapter Local Area Connection:
    Connection-specific DNS Suffix . :
    Description . . . . . . . . . . . : Intel(R) 82562V-2 10/100 Network Connecti
    on
    Physical Address. . . . . . . . . : 00-1D-09-8D-C3-05
    DHCP Enabled. . . . . . . . . . . : Yes
    Autoconfiguration Enabled . . . . : Yes
    IPv4 Address. . . . . . . . . . . : 192.168.1.148(Preferred)
    Subnet Mask . . . . . . . . . . . : 255.255.255.0
    Lease Obtained. . . . . . . . . . : Tuesday, March 18, 2008 1:30:24 PM
    Lease Expires . . . . . . . . . . : Thursday, March 20, 2008 10:15:18 PM
    Default Gateway . . . . . . . . . : 192.168.1.1
    DHCP Server . . . . . . . . . . . : 192.168.1.1
    DNS Servers . . . . . . . . . . . : 192.168.1.1
    NetBIOS over Tcpip. . . . . . . . : Enabled

    Tunnel adapter Local Area Connection* 6:
    Connection-specific DNS Suffix . :
    Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
    Physical Address. . . . . . . . . : 02-00-54-55-4E-01
    DHCP Enabled. . . . . . . . . . . : No
    Autoconfiguration Enabled . . . . : Yes
    IPv6 Address. . . . . . . . . . . : 2001:0:cf2e:308c:840:28a7:b86d:60d8(Prefe
    rred)
    Link-local IPv6 Address . . . . . : fe80::840:28a7:b86d:60d8%8(Preferred)
    Default Gateway . . . . . . . . . : ::
    NetBIOS over Tcpip. . . . . . . . : Disabled

    Tunnel adapter Local Area Connection* 9:
    Media State . . . . . . . . . . . : Media disconnected
    Connection-specific DNS Suffix . :
    Description . . . . . . . . . . . : isatap.{0EF93713-250B-4E9B-97B9-96782FC06
    D26}
    Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
    DHCP Enabled. . . . . . . . . . . : No
    Autoconfiguration Enabled . . . . : Yes
     
  10. kevanj

    kevanj LI Guru Member

    What I meant was are all three IPs leased to the same MAC active on the network at the same time....
     
  11. LLigetfa

    LLigetfa LI Guru Member

    My guess is the PC is getting a new lease when it comes out of powersave because that is what it's asking for. ISTR reading about patches to the OS to fix that issue.
     
  12. TexasFlood

    TexasFlood Network Guru Member

    My IPs are all set to static but I removed one to test. I got a DHCP address out of the pool then released the lease and renewed a few times. Got the same lease back every time. I remember when I was at my sister's place over Christmas that I saw "zombie" DHCP leases like these on her wireless router (an old Microsoft MN-500) that were no longer in use but yet to expire. Since she only uses a small percentage of the available DHCP pool and there were only a couple of zombies which would time out after a while, this didn't seem to be a real cause for concern. These leases probably only exist in the router's table with the client only recognizing the lease without the '*'. I'm not sure why the same lease isn't getting renewed. Maybe you can find a clue in the logs but it might not really matter in your case as it didn't in my sister's case.
     
  13. lordielordie

    lordielordie LI Guru Member


    This PC is setup as "always on"....
     
  14. lordielordie

    lordielordie LI Guru Member


    I tried that.. I gave this PC a static address, and I still see 2 other IP addresses assigned to the same MAC address..

    this is driving me nuts.
     
  15. LLigetfa

    LLigetfa LI Guru Member

    Your cat hit the sleep button. I taped over my sleep button after hitting it a few times.
     
  16. lordielordie

    lordielordie LI Guru Member

    here is what it looks like in the log:

    Mar 21 08:13:36 daemon.info dnsmasq[10322]: DHCPREQUEST(br0) 192.168.1.149 00:1d:09:8d:c3:05
    Mar 21 08:13:36 daemon.info dnsmasq[10322]: DHCPACK(br0) 192.168.1.149 00:1d:09:8d:c3:05 tabor
    Mar 21 08:13:36 daemon.info dnsmasq[10322]: DHCPREQUEST(br0) 192.168.1.151 00:1d:09:8d:c3:05
    Mar 21 08:13:36 daemon.info dnsmasq[10322]: DHCPACK(br0) 192.168.1.151 00:1d:09:8d:c3:05 tabor

    What can this be? it looks like the PC is asking for a RENEW for those 2 addresses (149 and 152)... where in Vista can this be hiding??

    Right now the router is set up with this PC as static 192.168.1.100 and as you can see the PC did a DHCP request less then an hour before renewing 1.100
    Mar 21 07:30:48 daemon.info dnsmasq[10322]: DHCPINFORM(br0) 192.168.1.100 00:1d:09:8d:c3:05
    Mar 21 07:30:48 daemon.info dnsmasq[10322]: DHCPACK(br0) 192.168.1.100 00:1d:09:8d:c3:05 tabor

    crazy, no?
     
  17. TexasFlood

    TexasFlood Network Guru Member

    It is really strange that the "bonus" IP related messages both have the exact same timestamp (Mar 21 08:13:36). I did a bit of googling but didn't find anything very helpful.

    Couple of questions.

    1) I think I know the answer to this but just to be sure, what happens if you try to ping those 192.168.1.149 and 192.168.1.151 addresses? I assume it just times out and fails but one never knows until one tries.

    2) Were those log entries relating to the *.149 and *.151 addresses before or after you set the static address. If before, they may just not yet have timed out, maybe reboot the router and check again.
     
  18. lordielordie

    lordielordie LI Guru Member


    I will not have an opportunity to do the pinging until Monday, but I also assume that they'll time out.

    I made sure to delete those 2 entries from the router after I set up the static address, and they got reissued. In the past 4 days I saw it as 148, 149, 150, or 151, and all kinds of combinations.. every time I delete those 2 extra entries from the router's device list (by clicking on the "lease time") they get reissued and the addresses are different most of the times..

    My got feel is that it is a combination of Tomato and Vista issue.. Another thing I could try to work around the problem is the to make the PC non-DHCP and fix the address and gateway, but that will not solve the problem, just work around it..
     
  19. TexasFlood

    TexasFlood Network Guru Member

    I don't really trust Vista as of yet. The only Vista laptop that has connected to my wireless network has had problems. Quite a number of XP desktops & laptops, games machines, etc have been able to connect without issue - well except for those brief times I've run version of firmware with problems & before falling back to something stable. We upgraded all the network related drives on that Vista laptop but didn't get a chance to retest it here yet.
     
  20. hrts

    hrts LI Guru Member

    Saw that behavior ...but not related with Vista.
    Just for my curiosity - do you have ane software HBA (host bus adapters)/SCSI adapters or SAN devices on your PC/network?

    I do have a small SAN attached to the router and is asking from same network card for 2 IPs all the time. On my PC I have some software drivers for SCSI bus adapters that "hot plugs" the SAN volumes to my laptop. Once I've saw a strange MAC in my laptop ipconfig/all report with an IP attached. As soon as I upgraded the SCSI adapter drivers and SAN firmware the strange behaviour dissapeared. Now I have only the 2 requests from SAN but this time from 2 MAC even if there is a single network card in that SAN.

    Never figured out what is the cause but at least one of duplicated IP dissapered and I belive that was the SCSI virtual adapter to blame.
    In HP servers the HBA adapters act as ethernet adapters and request 2 IPs: one for management and one for traffic. I guess that same design was used in my software SCSI driver.

    Have a look here: none of these MAC addresses are real (I've checked the OUI and is not registered to my SAN producer - in fact the OUI is not registered at all), but all are generated by my SAN box (the real MAC is having the OUI 00:18:4d - NetGear California registered)

    May 6 22:12:02 ygh daemon.info dnsmasq[118]: DHCPDISCOVER(br0) 02:18:4d:xx:xx:xx
    May 6 22:12:02 ygh daemon.info dnsmasq[118]: DHCPOFFER(br0) 192.168.10.144 02:18:4d:xx:xx:xx
    May 6 22:12:02 ygh daemon.info dnsmasq[118]: DHCPREQUEST(br0) 192.168.10.144 02:18:4d:xx:xx:xx
    May 6 22:12:02 ygh daemon.info dnsmasq[118]: DHCPACK(br0) 192.168.10.144 02:18:4d:xx:xx:xx
    May 6 22:12:06 ygh daemon.info dnsmasq[118]: DHCPDISCOVER(br0) 02:18:4d:yy:yy:yy
    May 6 22:12:06 ygh daemon.info dnsmasq[118]: DHCPOFFER(br0) 192.168.10.148 02:18:4d:yy:yy:yy
    May 6 22:12:06 ygh daemon.info dnsmasq[118]: DHCPREQUEST(br0) 192.168.10.148 02:18:4d:yy:yy:yy
    May 6 22:12:06 ygh daemon.info dnsmasq[118]: DHCPACK(br0) 192.168.10.148 02:18:4d:yy:yy:yy
     
  21. kzrssk

    kzrssk LI Guru Member

    Is that machine your VPN server? I know that Microsoft Routing and Remote Access servers will buy up all the IPs they need to feed their incoming connections. So if you are running a Microsoft VPN server with two connections, that's probably where it's coming from.
     
  22. hrts

    hrts LI Guru Member

    Hi.
    No, is not MS VPN server. Is a "plain" XP Sp2. Running on a laptop with 2 network cards: WiFi adapter and Wired/Cat5 adapter.
    The only "unusual" thing in this XP are the SCSI and HBA virtual adapters that scans continuosly the network for any SFS (SAN File System) presence and try to plug to the virtual drives published on the network by my small SAN.

    On the other hand, the router itself is OpenVPN server (so I don't need the MS VPN because I have a better one :D) but this one is requesting and releasing correctly the IPs as soon as I connect. I am extracting constantly the "openvpn.log" and "openvpn-status.log" plus "messages" files from Tomato router and I saw no problems generated by the OpenVPN server. I have to accept the fact that I do not know how my SAN works (both the hardware box and virtual adapters installed on my laptop) and I am blaming it for this. As soon as I power it down all the logs /device list report are OK.

    Late edit: my particular problem is caused by the SAN: http://kbserver.netgear.com/kb_web_files/n101563.asp

    Each partition created on the SAN has an unique Identifier and request an unique IP address!
    So my SAN get's 2 IPs now: one for management and one for the partition. I will create the second partition and as result my SAN box should request the 3rd IP from Tomato...

    In the example shown by my SAN producers there are 5 IPs alocated to same MAC: one for management and 4 for each partition published by the SAN over the network.
     

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