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backtick in branch id RRS feed

  • Question

  • Hi

    I am running into a problem where lync (both 2010 and 2013) edge server is silently dropping random packets.

    Looking in the edge logs, I found this error: 

    TL_WARN(TF_DIAG) [0]0560.0984::09/16/2015-12:59:05.537.00147429 (SIPStack,SIPAdminLog::TraceDiagRecord:SIPAdminLog.cpp(145))$$begin_record
    LogType: diagnostic
    Severity: warning
    Text: Routing error occurred; check Result-Code field for more information
    Result-Code: 0xc3e93f27 SIPPROXY_E_INVALID_VIA_ENTRY

    On close analysis we found that whenever the branch id in the top most via header contains a backtick (`), lync edge server gives this error and drops the packet.

    However, the SIP RFC (3261, 3265) doesn't restrict the use of this character in branch id. Neither does SIP Torture RFC (5118) restrict this character.

    Could anyone help me out in this? 

    Thursday, September 17, 2015 7:01 AM

All replies

  • Hi, Sometimes misconfiguration of Edge server causes packet drop and intermittent issues. Make sure these checks are performed on all your Edge servers -

    1. Internal and external NICs subnets must not be routable to each other.

    2. On the internal interface, configure one static IP address on the internal perimeter network subnet and do not set a default gateway. Configure adapter DNS settings to point to at least one DNS server, preferably a pair of perimeter DNS servers.

    3. Configure default gateway on external interface NIC. For example, define the Internet-facing router or the external firewall as the default gateway.

    4. Configure DNS settings to point to a DNS server on external NIC, preferably to a pair of external DNS servers.

    5. On the internal interface, configure one static IP address on the internal perimeter network subnet and do not set a default gateway. Leave adapter DNS settings empty.

    6. Edit the HOST file on each Edge Server to contain a record for the next hop server or virtual IP (VIP) (the record will be the Director, Standard Edition server, or a Front End pool that was configured as the Edge Server next hop address in Topology Builder). If you are using DNS load balancing, include a line for each member of the next hop pool.


    • Proposed as answer by GAUTAM8451 Monday, October 24, 2016 9:24 AM
    Friday, April 29, 2016 10:27 AM