Extreme Networks ExtremeWare 7.2e, Installation And User Manual

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Overview of the EAPS Protocol
ExtremeWare 7.2e Installation and User Guide 183
Figure 29: EAPS operation
If the ring is complete, the master node logically blocks all data traffic in the transmit and receive
directions on the secondary port to prevent a loop. If the master node detects a break in the ring, it
unblocks its secondary port and allows data traffic to be transmitted and received through it.
EAPS Terms
Table 33 describes terms associated with EAPS.
Table 33: EAPS Terms
Term Description
EAPS domain A domain consists of a series of switches, or nodes, that comprise a single ring in a
network. An EAPS domain consists of a master node, transit nodes, and on the
master node, one primary port and one secondary port. EAPS operates by declaring
an EAPS domain on a single ring.
EDP Extreme Discovery Protocol. A protocol used to gather information about neighbor
Extreme switches. Extreme switches use EDP to exchange topology information.
master node A switch, or node, that is designated the master in an EAPS domain ring. The
master node blocks the secondary port for all non-control traffic belonging to this
EAPS domain, thereby avoiding a loop in the ring.
transit node A switch, or node, that is not designated a master in an EAPS domain ring.
primary port A port on the master node that is designated the primary port to the ring. The transit
node ignores the primary port distinction as long as the node is configured as a
transit node.
secondary port A port on the master node that is designated the secondary port to the ring. The
transit node ignores the secondary port distinction as long as the node is configured
as a transit node.
control VLAN A VLAN that sends and receives EAPS messages. You must configure one control
VLAN for each EAPS domain.
EW_071
Direction of
health-check
message
Master
node
Secondary port
is logically blocked
S 4
S 5
S 6
S 3
S 2
S 1
S P