Cisco Cisco TelePresence Video Communication Server Expressway
Appendix 1 - Troubleshooting
Cisco VCS Deployment Guide: Microsoft Lync 2010 and Cisco VCS X6.1
Page 56 of 81
Prior to version 1.5 the ISDN GW sent RTP traffic from SSRC = 0; Lync would not accept RTP traffic
with SSRC = 0.
with SSRC = 0.
From version 1.5 the ISDN GW sends RTP traffic from a random, non zero, SSRC and Lync receives
this correctly.
this correctly.
No video through an ISDN gateway
Some ISDN endpoints initiate a call using one set of codecs, then before media is sent, change the
codecs to better codecs (for example an initial offering of H.261 is updated to H.263). Lync doesn’t
accept a change in codec before media is sent.
codecs to better codecs (for example an initial offering of H.261 is updated to H.263). Lync doesn’t
accept a change in codec before media is sent.
To work around this, “Meet me” on a conference, so that the ISDN endpoint sets up a call and
connects to the MCU and Lync sets up a call and connects to the MCU independently.
connects to the MCU and Lync sets up a call and connects to the MCU independently.
Call to PSTN or other device requiring caller to be authorized
fails with 404 not found.
fails with 404 not found.
In Some Lync Server configurations, especially where Lync Server PSTN gateways are used, calls are
only allowed to be made if the calling party is authorized. This actually means that the calling party’s
domain must be the Lync Server ’s domain.
only allowed to be made if the calling party is authorized. This actually means that the calling party’s
domain must be the Lync Server ’s domain.
For calls from endpoints that are not part of a FindMe™ this means that the endpoints must register to
the video network with a domain that is the same as the Lync Server domain.
the video network with a domain that is the same as the Lync Server domain.
For calls from endpoints that are part of a FindMe™ the endpoints can register with any domain so
long as the FindMe™ ID has the same domain as Lync Server and in the FindMe™ configuration
Caller ID is set to FindMe ID (instead of Incoming ID).
long as the FindMe™ ID has the same domain as Lync Server and in the FindMe™ configuration
Caller ID is set to FindMe ID (instead of Incoming ID).
Lync endpoints try to register with Cisco VCS Expressway.
SIP video endpoints usually use DNS SRV records:
•
_sips._tcp.<domain>
•
_sip._tcp.<domain> and
•
_sip._udp.<domain>
in that order to route calls to Cisco VCS.
Lync uses:
•
_sipinternaltls._tcp.<domain> - for internal TLS connections
•
_sipinternal._tcp. <domain>
- for internal TCP connections (only if TCP is allowed)
•
_sip._tls. <domain>
- for external TLS connections
Lync only supports TLS connection to the Edge Server. The _sip._tcp.<domain> DNS SRV record
should be used for the Cisco VCS Expressway. Configure Lync to use encryption (set Lync Server to
‘Supports encryption’ – as specified in the configuration process).
should be used for the Cisco VCS Expressway. Configure Lync to use encryption (set Lync Server to
‘Supports encryption’ – as specified in the configuration process).
OCS Relay problems
OCS Relay FindMe™ users take a long time to register.
OCS Relay can take up to 3 minutes to pick up a new OCS Relay FindMe™ entry and register it. If a
number of entries get deleted and the same number get added, it can take OCS Relay up to 60
minutes to observe the change in identities and update the registrations.
number of entries get deleted and the same number get added, it can take OCS Relay up to 60
minutes to observe the change in identities and update the registrations.