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Question about DHCP Start address????

GuerrillaGuerrilla Posts: 12
in Connectivity Jan 16, 2018

I read in one of the threads when I searched for TG1672G that msraye mentioned dont use any single last digits for lan terminal services (why should you not use any single last digits?) I have mine DHCP start at zero point two should I change this?  Im wondering if I have my modem setup wrong.  I keep losing a valid IP address and Im wondering if its because DHCP is setup wrong.  Im new to this ubee DVW32CB modem.  I love it but Im wondering if there is anything wrong with my setup?  Im going to be working on this problem today and see if I cant fix it but if anybody could help me that would be awesome.


  • scjrscjr Posts: 73
    Jan 16, 2018

    Are you having issues with Apple devices? I had that modem at one time and my Apple devices would hang and appear to be connected. I had to restart the Wi-Fi on the device to connect again. Never really was able to figure it out. I have my own modem and router now, with no issues.


    You should copy/paste your modem signals here, so MsRaye and others can take a look.


    According to MsRaye:


    set the DHCP start to and allow 25-50 units.
    Put any static ip's @ on down.
    Single last digits are a user class error and Apples especially don't like them
    Turn off WPS and any sort of guest wifi access
  • karlbeckmankarlbeckman Posts: 2,205 ✭✭✭✭
    Jan 16, 2018

    Many Apple products have severe problems when the last octet of their IP address is a single decimal digit.  When you set DHCP start for at least a valid user class is detected and data transfer works properly.  We suggest that you start DHCP even higher, at either 50 or 100, and use the lower space to assign static IP addresses for wireless printers, wireless cameras,  Next devices, video streaming adaptors, and other 'permanent' units that always remain within wired ethernet or WiFi range [do NOT do this to your cell phones}.   BTW, this one step solves almost every "I have to restart my wireless printer every time ..." complaint.

  • GuerrillaGuerrilla Posts: 12
    Jan 16, 2018

    I can change the last digit and I did to one hundred from two and then it says number of CPE's its one hundred and fifty five should I change that if I change the last digit on the one.  Also I noticed the lease time was thirty six hundred seconds and thats one hour I changed that to eighty six thousand four hundred seconds twenty four hours and just realized IPvSix was lease time thirty six hundred seconds to I changed that to eighty six thousand four hundred seconds to twenty four hours.  I can see the signals page but the ubee DVW32CB modem router combo doesnt have error logs?


    I think the lease time was the problem.  Im going to see I think I changed the DHCP starting address correctly.  I downloaded the ubee DVW32CB router modem combo user guide and it helped me with the lease time but it doesnt mention error logs?

  • reds91185reds91185 Posts: 2,452
    Jan 16, 2018

    If your devices were disconnecting every hour on the hour then your issue was lease time, not DHCP settings. The default DHCP settings work fine 99.9% of the time, but every so often the wireless printer or Apple device will not play nice but that is the exception.

  • karlbeckmankarlbeckman Posts: 2,205 ✭✭✭✭
    Jan 16, 2018

    I agree with reds91185 that your real issue was DHCP lease renewal time.  It should be set for one day, not one hour.  That's a common setup error-TWC does it many times every day! 

    As for changing the number of CPE addresses, YES!  There are a total of 253 available, so if you change DHCP start to 100 there are only 153 available for DHCP to assign (.Zero and .255 are both reserved and .1 is assigned to the router).

  • GuerrillaGuerrilla Posts: 12
    Jan 16, 2018

    The number of CPE's for the private starting address  is one hundred and fifty five right now what should I set it to?  Should I set it to two hundred and fifty five or two hundred and fifty three?  I havent had connection issues for hours the lease time was the problem.  Ill keep the CPE's at one hundred and fifty five unless one of you or someone here tells me I should change it.

  • GuerrillaGuerrilla Posts: 12
    Jan 17, 2018

    Ok I had a good connection for four to six hours may have been eight hours then I lost connection got a red X between the modem and the isp in the network map on network and sharing center I clicked on it and it said The dns server is not responding.  Im using Time warner Cable's DNS server's are they good or should I use different DNS server's?  Also here is my signals page:


    Connectionimage> Status > Connection

    Startup ProcedureProcedure Status Comment
    Acquire Downstream Channel633000000 HzLocked
    Connectivity StateOKOperational
    Boot State  
    Configuration FileOK 
    Downstream Bonded ChannelsChannel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
    1 QAM256 633000000 Hz4.8 dBmV38.5 dB00
    2 QAM256 627000000 Hz4.9 dBmV38.5 dB00
    3 QAM256 639000000 Hz4.8 dBmV38.4 dB00
    4 QAM256 657000000 Hz5.2 dBmV38.4 dB00
    5 QAM256 651000000 Hz5.1 dBmV38.4 dB120
    6 QAM256 663000000 Hz5.4 dBmV38.4 dB00
    7 QAM256 681000000 Hz5.8 dBmV38.2 dB00
    8 QAM256 687000000 Hz5.6 dBmV38.0 dB90
    9 QAM256 711000000 Hz6.0 dBmV37.8 dB00
    10 QAM256 693000000 Hz5.8 dBmV38.1 dB00
    11 QAM256 675000000 Hz5.7 dBmV37.9 dB130
    12 QAM256 723000000 Hz6.0 dBmV37.5 dB00
    13 QAM256 729000000 Hz6.1 dBmV37.4 dB00
    14 QAM256 753000000 Hz5.7 dBmV37.1 dB00
    15 QAM256 741000000 Hz6.1 dBmV37.3 dB00
    16 QAM256 747000000 Hz5.8 dBmV37.2 dB00
    Total Correctables Total Uncorrectables
    Upstream Bonded ChannelsChannel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
    1 ATDMA 5120 Ksym/sec37000000 Hz48.0 dBmV
    2 TDMA 2560 Ksym/sec19400000 Hz46.0 dBmV
    3 ATDMA 5120 Ksym/sec24200000 Hz47.0 dBmV
    4 ATDMA 5120 Ksym/sec30600000 Hz47.8 dBmV
    Everything was working good why did my dns stop responding?  this is really making me angry.
  • MsRayeMsRaye Posts: 25,606
    Jan 18, 2018

    I've seen something screwy going on with the DNS as well eally intermittent, maybe a couple times a day.

    ... Real long time to resolve routing...

    Are you running IPv6 on anything? that's been an issue with timeouts, if so turn IPv6 off



  • GuerrillaGuerrilla Posts: 12
    Jan 18, 2018

    I shut off IPvSix on the modem the DHCP still happening also changed MTU to fifteen hundred it says zero is default is that normal I thought MTU was supposed to be fourteen hundred and something to fifteen hundred?  Also I checked multicast.  Can I uninstall IPvSix from windows seven I have heard its horrible with leaks?  I did that dns benchmark test from steve gibson and it said one dns address was good the one with the last digit of sixty one. 


    If you say there have been issues with it intermittent then that makes me feel better means it could be fixed I hope what dns should I use for now? Ill try google unless you have a better suggestion?  I hope this dns server issue gets fixed this week or this month its really annoying getting disconnected from the internet.


    I just saw this in the firewall tab local log:


    TCP- or UDP-based Port Scan 1  Sat Jan 13 15:15:06 2018   My Public IP Address:54375 
    TCP- or UDP-based Port Scan 319  Wed Jan 17 22:53:00 2018   My Public IP Address:47936 
    TCP- or UDP-based Port Scan 79  Tue Jan 16 19:40:43 2018   My Public IP Address:49254 
    TCP- or UDP-based Port Scan 8  Mon Jan 15 16:57:42 2018   My Public IP Address:60011 
    TCP- or UDP-based Port Scan 1  Tue Jan 16 11:00:52 2018   My Public IP Address:51587 


    Whats with the port scan I saw yesterday it was at one hundred and ninety nine?  Now its at Three hundred nineteen the source is the time warner cable dns address with the last digit of sixty one?  DId someone hack into the time warner cable dns servers and using them to port scan people or have them been hijacked what is going on here?  Port scans can cause a dos or DDoS if done many times correct me if Im wrong?  If this is a malicious person I hope spectrum gets them.

  • karlbeckmankarlbeckman Posts: 2,205 ✭✭✭✭
    Jan 20, 2018

    It's probably Spectrum polling their network periodically, not a malicious port scan .  Now put the MTU setting back to its previous value. 

  • MsRayeMsRaye Posts: 25,606
    Jan 20, 2018

    These are DNS ports....

    TCP- or UDP-based Port Scan 319  Wed Jan 17 22:53:00 2018   My Public IP Address:47936 
    TCP- or UDP-based Port Scan 79  Tue Jan 16 19:40:43 2018   My Public IP Address:49254 
    TCP- or UDP-based Port Scan 8  Mon Jan 15 16:57:42 2018   My Public IP Address:60011 
  • GuerrillaGuerrilla Posts: 12
    Jan 21, 2018

    Polling its network?  Well whatever was happening it looks like it is done happening I dont want to jinx myself.  Now put the MTU setting back to its previous value?  Sounds like your giving me orders or something I dont like the way that sounded.  Also I know the first two are time warner cables dns server's with dns port and the third is google's dns server.  Everything is working ok so far Im going to leave it alone. 


    Ill let you know if I have any additional problems.  Just a question what do you mean polling its network periodically?  three hundred and nineteen times is not periodically.  I have checked the modem and the MTU setting was at zero I must have changed it back and there is now six hundred port scans Im not sure what was causing the problem it looks like the problem is fixed.  If it happens again Im going to post again Im happy my internet is working unhappy that I didnt find out what was happening if it happens again I dont know what to do ill post here again.  Thank you for trying to help me.

  • MsRayeMsRaye Posts: 25,606
    Jan 21, 2018

    Do you understand how dynamic route addressing works?

     THere is no fixed servers from ISP 1 user A's thru ISP 1's servers thru Itransport provider 2,3,4 to host server B. 2,3,4 may change from minute to minute

    These paths can change from minute to minute depending on traffic loads and interconnecting status. DNS is constantly updating and that's why it's dynamic not static. The DNS cache converts www.xxx to actual IP addy's and those change as well.

    It's why DNS caches need to be periodicly flushed to obtain a new table.

     Next issue is antivirus TSR's, there's always back and forth packets to stay updated. If those are interupted , the OS needs to see why and take corrective action if it's a viral/malware attack



  • GuerrillaGuerrilla Posts: 12
    Jan 22, 2018

    I understand how it works somewhat you probably understand better then me (dynamic route addressing dynamic IP address and a static IP Address yes I understand one is temporary IP Address thats why if you have a dynamic IP Address you get a lease time on your IP Address and one is a permanent IP Address).  I do understand that DNS converts name to IP Address.  I completely understand antivirus TSR terminate but stay resident programs.  I lost my internet connection again I hope it doesnt start doing the interrmittent crap again.  I could have been getting Dosed or DDoSed but I dont know if I have problems again Ill call spectrum like I did before I get faster responses that way.  Thank you for any new information you gave me.

  • MsRayeMsRaye Posts: 25,606
    Jan 22, 2018

    Copy and paste the modems signal level and error log pages, there should be some indication of what the outtage ws.


This discussion has been closed.