ECS4100 Series Web Management Guide-R07

Table Of Contents
Chapter 13
| Basic Administration Protocols
Ethernet Ring Protection Switching
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port connected to the next node in the ring to the east (or clockwise direction)
and another port facing west in the ring.
3. Configure the RPL owner (Configure Domain – Configure Details): Configure
one node in the ring as the Ring Protection Link (RPL) owner. When this switch
is configured as the RPL owner, the west ring port is set as being connected to
the RPL. Under normal operations (Idle state), the RPL is blocked to ensure that
a loop cannot form in the ring. If a signal failure brings down any other link in
the ring, the RPL will be unblocked (Protection state) to ensure proper
connectivity among all ring nodes until the failure is recovered.
4. Configure ERPS timers (Configure Domain – Configure Details): Set the Guard
timer to prevent ring nodes from receiving outdated R-APS messages, the
Hold-off timer to filter out intermittent link faults, and the WTR timer to verify
that the ring has stabilized before blocking the RPL after recovery from a signal
failure.
5. Configure the ERPS Control VLAN (Configure Domain – Configure Details):
Specify the Control VLAN (CVLAN) used to pass R-APS ring maintenance
commands. The CVLAN must NOT be configured with an IP address. In addition,
only ring ports may be added to the CVLAN (prior to configuring the VLAN as a
CVLAN). No other ports can be members of this VLAN (once set as a CVLAN).
Also, the ring ports of the CVLAN must be tagged. Failure to observe these
restrictions can result in a loop in the network.
6. Enable ERPS (Configure Global): Before enabling a ring as described in the next
step, first globally enable ERPS on the switch. If ERPS has not yet been enabled
or has been disabled, no ERPS rings will work.
7. Enable an ERPS ring (Configure Domain – Configure Details): Before an ERPS
ring can work, it must be enabled. When configuration is completed and the
ring enabled, R-APS messages will start flowing in the control VLAN, and
normal traffic will begin to flow in the data VLANs. A ring can be stopped by
disabling the Admin Status on any node.
8. Display ERPS status information (Configure Domain – Show): Display ERPS
status information for all configured rings.
Configuration Limitations for ERPS
The following configuration limitations apply to ERPS:
The switch supports up to six ERPS rings – each ring must have one Control
VLAN, and at most 255 Data VLANs.
Ring ports can not be a member of a trunk, nor an LACP-enabled port.
Dynamic VLANs are not supported as protected data ports.
Exclusive use of STP or ERPS on any port.