locked
Lync Phone Edition - Registrar FQDN cannot be found RRS feed

  • Question

  • Hi,

    I have finally got Lync phone edition devices into a separate VLAN.  All working ok, except when logging in they pause for about 5-10 seconds with error "Registrar FQDN cannot be found".  They then sign in and work perfectly.  Option 120 is setup on DHCP and was working fine when they were in the same VLAN as the server.  I am using an IP Helper to allow the phones to get their DHCP settings for our DHCP server.

    Our Lync Servers (FE and Edge Internal interface) are in VLAN 10 with subnet 192.168.10.0/24.
    Our DHCP is yet to be moved into our server VLAN and is currently in VLAN 0 10.81.108.0/22.
    Our Lync Phone devices are in VLAN 20 192.168.20.0/24.

    When I run DHCPUtil.exe -emulateclient on another computer in the 10.81.108.0/22 subnet, I get the following result:

    Result: Success
    DHCP Server : 10.81.108.11
    SIP Server FQDN :
    Certificate Provisioning Service URL : https://SR-LC-01.OPG.INTERNAL:443/CertProv/CertProvisioningService.svc

    It doesn't appear to be receiving the option 120 information from our DHCP server.  But this is setup as follows:

    The other DHCP options required for the phones are being pulled down successfully, but this one appears to be failing.  Please help!

    Many Thanks,

    Andrew

    Friday, April 11, 2014 10:25 AM

Answers

  • I have had a similar issue in the past and it turned out to be the IP Helper, managed to narrow it down by running DHCPUtil in the same VLAN as the phones. Then tried a phone in the same VLAN as the servers.  That isolated it for me before.


    Please remember, if you see a post that helped you please click "Vote As Helpful" and if it answered your question, please click "Mark As Answer"
    Lync Sorted blog


    • Proposed as answer by Lisa.zheng Thursday, April 17, 2014 5:47 AM
    • Marked as answer by Lisa.zheng Monday, April 21, 2014 2:26 AM
    • Edited by PaulB_NZMVP Monday, April 21, 2014 8:10 AM typos
    Saturday, April 12, 2014 7:13 PM

All replies

  • I have had a similar issue in the past and it turned out to be the IP Helper, managed to narrow it down by running DHCPUtil in the same VLAN as the phones. Then tried a phone in the same VLAN as the servers.  That isolated it for me before.


    Please remember, if you see a post that helped you please click "Vote As Helpful" and if it answered your question, please click "Mark As Answer"
    Lync Sorted blog


    • Proposed as answer by Lisa.zheng Thursday, April 17, 2014 5:47 AM
    • Marked as answer by Lisa.zheng Monday, April 21, 2014 2:26 AM
    • Edited by PaulB_NZMVP Monday, April 21, 2014 8:10 AM typos
    Saturday, April 12, 2014 7:13 PM
  • I have exactly this same problem with Registrar FQDN cannot be found for about 30 sec, and when phone finally signed in I have about 5-10 seconds time out before proper call but only in new Vlan, in old vlan works fine

    How haveyou resolve this issue

    Wednesday, August 26, 2015 8:46 AM