Routing DHCP
Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: Routing DHCP

  1. #1
    Junior Member
    Join Date
    Nov 2004
    Posts
    6

    Routing DHCP

    I seem to be having trouble getting this router to forward DHCP to a remote network over frame. I have enabled the helper address on the ethernet interface. (Which usually does the trick) For some reason it just wont work. Any ideas?

    Using 1274 out of 29688 bytes
    !
    version 12.0
    service timestamps debug uptime
    service timestamps log uptime
    no service password-encryption
    !
    hostname ********
    !
    no logging console
    enable secret 5 **********************
    !
    username ********* password **********
    !
    !
    !
    !
    memory-size iomem 25
    ip subnet-zero
    !
    !
    !
    !
    interface Serial0
    ip address 192.168.254.4 255.255.255.0
    no ip directed-broadcast
    encapsulation frame-relay IETF
    no fair-queue
    service-module t1 timeslots 1-8
    frame-relay interface-dlci 100
    frame-relay lmi-type ansi
    !
    interface FastEthernet0
    description Connected to Corporate Network
    ip address 192.168.100.10 255.255.255.0
    ip helper-address 192.168.0.5
    no ip directed-broadcast
    half-duplex
    !
    router eigrp 10
    network 192.168.100.0
    network 192.168.254.0
    no auto-summary
    !
    router rip
    redistribute connected
    redistribute static
    network 192.168.100.0
    network 192.168.254.0
    no auto-summary
    !
    ip classless
    no ip forward-protocol udp netbios-ns
    no ip forward-protocol udp netbios-dgm
    ip route 0.0.0.0 0.0.0.0 192.168.254.1
    no ip http server
    !
    !
    line con 0
    login local
    transport input none
    line aux 0
    login local
    modem InOut
    transport input all
    speed 115200
    flowcontrol hardware
    line vty 0 4
    login local
    !
    no scheduler allocate
    end

  2. #2
    THE Bastard Sys***** dinowuff's Avatar
    Join Date
    Jun 2003
    Location
    Third planet from the Sun
    Posts
    1,252
    Only time I've ever screwed up DHCP over Frame is when I had one or more of the following blcked on one or both sides.


    TFTP (port 69)
    DNS (port 53)
    Time (port 37)
    TACACS (port 49)
    BOOTP client (port 68)
    BOOTP server (port 67)
    NetBIOS name service (port 137)
    NetBIOS datagram service (port 138)

  3. #3
    Junior Member
    Join Date
    Nov 2004
    Posts
    6
    Originally posted here by dinowuff
    Only time I've ever screwed up DHCP over Frame is when I had one or more of the following blcked on one or both sides.


    TFTP (port 69)
    DNS (port 53)
    Time (port 37)
    TACACS (port 49)
    BOOTP client (port 68)
    BOOTP server (port 67)
    NetBIOS name service (port 137)
    NetBIOS datagram service (port 138)
    Blocking Netbios services shouldn't have any effect. I have to block them, or esle I get flooded with master browser requests. I have other routers setup with that configuration with no problem. Where this one differs from ther other routers that I manage, is the eigrp 10 section. I didn't set these up initialy so I'm not sure what purpose it serves. Is anyone familiar with eigrp and if it would affect DHCP?

  4. #4
    THE Bastard Sys***** dinowuff's Avatar
    Join Date
    Jun 2003
    Location
    Third planet from the Sun
    Posts
    1,252
    Should have been more specific:

    The ports listed I use for troubleshooting OPEN all then check. Just something I do.

    Anyway There were Enhanced Interior Gateway Routing Protocol (EIGRP) Defects years ago - I think in the late 90's in almost all versions of the cisco IoS. So what version of IoS and are the versions the same on both routers? -

    Also, Didn't see any IKE or IPSec settings. If You are using IPsec, the EIGRP setting would look something like this;

    router eigrp 10
    network 192.168.0 0.0.0.3
    network 192.168.2.0
    no auto-summary
    no eigrp log-neighbor-changes

  5. #5
    Junior Member
    Join Date
    Nov 2004
    Posts
    6
    It looks like the others are on 11.2 and this one is on 12.0. Hmm....

  6. #6
    THE Bastard Sys***** dinowuff's Avatar
    Join Date
    Jun 2003
    Location
    Third planet from the Sun
    Posts
    1,252
    Products Affected
    The Cisco IOS Software revisions below are affected by CSCdj60533 and CSCdj58676, except where noted.

    Software Release Images Affected Resolution
    11.2 All images 11.2(9.1) - 11.2(10), 11.2(10a) ** 11.2(11)
    11.2P All images 11.2(9.1)P - 11.2(10)P, 11.2(10a)P **+ 11.2(10a)P1, 11.2(11)P
    11.2BC All images 11.2(9.1)BC - 11.2(10)BC, 11.2(10a)BC ** 11.2(11)BC
    11.2XA All images 11.2(9)XA & 11.2(9)XA1 N/A ++
    11.1 * All images 11.1(15.1) - 11.1(15.5) 11.1(16)
    11.1AA * All images 11.1(15.1)AA - 11.1(15.5)AA 11.1(16)AA
    11.1CA * All images 11.1(15)CA - 11.1(15.5)CA 11.1(16)CA
    11.1IA * All images 11.1(15)IA - 11.1(15.5)IA 11.1(16)IA

    Here's the link: http://www.cisco.com/en/US/products/...80094457.shtml

    I feel for you

  7. #7
    Junior Member
    Join Date
    Nov 2004
    Posts
    6
    The thing is, the routers running 11.2 seem to be working fine. I'm handing out addresses to those networks with no problem. It's the router with 12.0 that I can't get to forward.

  8. #8
    THE Bastard Sys***** dinowuff's Avatar
    Join Date
    Jun 2003
    Location
    Third planet from the Sun
    Posts
    1,252
    hummm - are you using eigrp on all interfaces?

  9. #9
    Junior Member
    Join Date
    Nov 2004
    Posts
    6
    Apparently this is the only one with any reference to eigrp. I need to do my homework on what that exactly does. The others are connected in the exact same fashion. However, for some reason this one seems to have a more complicated config. I am hesitant to take anything out of it given there is no modem setup in that location in case it gets knocked off the frame. Here's an example of one that is forwarding DHCP without issue.

    Using 895 out of 7506 bytes
    !
    version 11.2
    no service password-encryption
    no service udp-small-servers
    no service tcp-small-servers
    !
    hostname ********
    !
    enable secret ***********
    !
    username ******** password *****
    !
    interface Ethernet0
    ip address 192.168.20.254 255.255.255.0
    ip helper-address 192.168.0.5
    no ip directed-broadcast
    !
    interface Serial0
    no ip address
    shutdown
    !
    interface Serial1
    description 512K Frame-Relay connection
    ip address 192.168.254.3 255.255.255.0
    encapsulation frame-relay IETF
    service-module t1 timeslots 1-8
    frame-relay interface-dlci 100
    frame-relay lmi-type ansi
    !
    router rip
    redistribute connected
    network 192.168.20.0
    network 192.168.254.0
    !
    no ip classless
    no ip forward-protocol udp netbios-ns
    no ip forward-protocol udp netbios-dgm
    no logging console
    snmp-server community public RO
    !
    line con 0
    login local
    line vty 0 4
    login local
    !
    end

  10. #10
    THE Bastard Sys***** dinowuff's Avatar
    Join Date
    Jun 2003
    Location
    Third planet from the Sun
    Posts
    1,252
    No prob -
    Rem out the serial config lines for eigrp. Or look up the command line - However you want to edit your configuration.

    Save the config - don't think you need to flash or reboot.

    Anyway - however you decide to change, removing the eigrp setting will get you back up and running.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •