Cisco Cisco TelePresence Video Communication Server Expressway 관리 매뉴얼
Clustering and peers
"Manual synchronization of configuration is required" warnings are raised on peer Cisco
VCSs
VCSs
1. Log in to the peer as admin through the CLI (available by default over SSH and through the serial
port).
2. Type xCommand ForceConfigUpdate.
This will delete the non-master Cisco VCS configuration and force it to update its configuration from
the master Cisco VCS.
the master Cisco VCS.
CAUTION:
never issue this command on the master Cisco VCS, otherwise all configuration for the
cluster will be lost.
Managing clusters and peers
Sharing registrations across peers
When one Cisco VCS in a cluster receives a search request (such as an LRQ, ARQ or an INVITE), it
checks its own and its peers' registration databases before responding. This allows all endpoints in the
cluster to be treated as if they were registered with a single Cisco VCS.
checks its own and its peers' registration databases before responding. This allows all endpoints in the
cluster to be treated as if they were registered with a single Cisco VCS.
Peers are periodically queried to ensure they are still functioning. To prevent delays during call setup,
any nonfunctioning peers do not receive LRQs.
any nonfunctioning peers do not receive LRQs.
H.323 registrations
All the peers in a cluster share responsibility for their H.323 endpoint community. When an H.323
endpoint registers with one peer, it receives a registration response which contains a list of alternate
gatekeepers, populated with a randomly ordered list of the IP addresses of all the other peers in that
cluster.
endpoint registers with one peer, it receives a registration response which contains a list of alternate
gatekeepers, populated with a randomly ordered list of the IP addresses of all the other peers in that
cluster.
If the endpoint loses contact with the initial peer, it will seek to register with one of the other peers. The
random ordering of the list of alternate peers ensures that endpoints that can only store a single
alternate peer will failover evenly across the cluster.
random ordering of the list of alternate peers ensures that endpoints that can only store a single
alternate peer will failover evenly across the cluster.
Note: when using a cluster, you should change the registration Time to live on all peers in the cluster
from the default 30 minutes to just a few minutes. This setting determines how often endpoints are
required to re-register with their Cisco VCS, and reducing this to just a few minutes ensures that if one
Cisco VCS becomes unavailable, the endpoint will quickly failover to one of its peers. To change this
setting, go to
from the default 30 minutes to just a few minutes. This setting determines how often endpoints are
required to re-register with their Cisco VCS, and reducing this to just a few minutes ensures that if one
Cisco VCS becomes unavailable, the endpoint will quickly failover to one of its peers. To change this
setting, go to
VCS configuration > Protocols > H.323 > Gatekeeper > Time to live
.
SIP registrations
Failover re-registration to a peer applies to H.323 re-registrations only.
The SIP standard currently has no direct equivalent, but some SIP UAs including Movi™ v2.0 (or later)
clients support similar functionality. If you configure such endpoints with a SIP server address that is
an FQDN, and configure this FQDN to resolve to a round-robin DNS record populated with the IP
addresses of all the peers in the cluster, then this could allow the endpoint to re-register with another
peer if its connection to the original peer was lost.
clients support similar functionality. If you configure such endpoints with a SIP server address that is
an FQDN, and configure this FQDN to resolve to a round-robin DNS record populated with the IP
addresses of all the peers in the cluster, then this could allow the endpoint to re-register with another
peer if its connection to the original peer was lost.
Sharing bandwidth across peers
When clustering has been configured, all peers share the bandwidth available to the cluster.
n
Peers must be configured identically for all aspects of bandwidth control including subzones, links
and pipes.
and pipes.
Cisco VCS Administrator Guide (X6)
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