Cisco Cisco Expressway
Notes:
■
Ensure that the
cisco-uds
SRV records are NOT resolvable outside of the internal network, otherwise the
Jabber client will not start mobile and remote access negotiation via the Expressway-E.
■
You must create internal DNS records, for both forward and reverse lookups, for all Unified Communications
nodes used with Mobile and Remote Access. This allows Expressway-C to find the nodes when IP addresses
or hostnames are used instead of FQDNs.
nodes used with Mobile and Remote Access. This allows Expressway-C to find the nodes when IP addresses
or hostnames are used instead of FQDNs.
DNS SRV Configuration for Legacy Video Conferencing Deployments
The format of DNS SRV queries for sip (RFC 3263) and H.323 used by Expressway are:
■
_sips._tcp.<fully.qualified.domain>
■
_sip._tcp.<fully.qualified.domain>
■
_sip._udp.<fully.qualified.domain> - not recommended for video calls, only use for audio-only calls
■
_h323ls._udp.<fully.qualified.domain> - for UDP location (RAS) signaling, such as LRQ
■
_h323cs._tcp.<fully.qualified.domain> - for H.323 call signaling
The format of DNS SRV queries for sip (RFC 3263) and H.323 typically used by an endpoint are:
■
_sips._tcp.<fully.qualified.domain>
■
_sip._tcp.<fully.qualified.domain>
■
_sip._udp.<fully.qualified.domain> - not recommended for video calls, only use for audio-only calls
■
_h323ls._udp.<fully.qualified.domain> - for UDP location (RAS) signaling, such as LRQ
■
_h323cs._tcp.<fully.qualified.domain> - for H.323 call signaling
Note that UDP is not a recommended transport medium for video signaling; SIP messaging for video system is too
large to be reliably carried on datagram-based (rather than stream-based) transports.
large to be reliably carried on datagram-based (rather than stream-based) transports.
The Expressway Cluster name (configured on the System > Clustering page) should be the <fully.qualified.domain>
specified in the DNS SRV records that point to the Expressway cluster.
specified in the DNS SRV records that point to the Expressway cluster.
Example
DNS SRV records for 2 peers of an Expressway-E cluster for example.com
where:
■
FQDN of Expressway-E peer 1: expe1.example.com
■
FQDN of Expressway-E peer 2: expe2.example.com
■
FQDN of Expressway-E cluster: example.com
_sips._tcp.example.com. 86400 IN SRV 1 1 5061 expe1.example.com.
_sips._tcp.example.com. 86400 IN SRV 1 1 5061 expe2.example.com.
_sip._tcp.example.com. 86400 IN SRV 1 1 5060 expe1.example.com.
_sip._tcp.example.com. 86400 IN SRV 1 1 5060 expe2.example.com.
_h323ls._udp.example.com. 86400 IN SRV 1 1 1719 expe1.example.com.
_h323ls._udp.example.com. 86400 IN SRV 1 1 1719 expe2.example.com.
_h323cs._tcp.example.com. 86400 IN SRV 1 1 1720 expe1.example.com.
_h323cs._tcp.example.com. 86400 IN SRV 1 1 1720 expe2.example.com.
Note that:
37
Cisco Expressway Cluster Creation and Maintenance Deployment Guide
Appendix 3: Cluster Name and DNS SRV Records