HP ProCurve 9304M Installation And Configuration Manual page 241

• Sync and Reroot – The Root port then asserts a sync and a reroot signal on all the ports on the bridge. The
signal tells the ports that a new Root port has been assigned and they are to renegotiate their new roles and
states. The other ports on the bridge assert their sync and reroot signals. Information about the old Root port
is discarded from all ports. Designated ports change into discarding states (Figure 8.10).
Figure 8.10 Sync and Reroot
Routing Switch 200
Port2
Sync
Reroot
Discarding
Port2
Routing Switch 300
Configuring Spanning Tree Protocol (STP) and Advanced STP Features
Routing Switch 100
Port2
Root port
Port1
Proposing
Port1
Root port
Sync
Reroot
Forwarding
Port4
Root port
Sync
Reroot
Discarding
Port3
Sync
Reroot
Discarding
Port3
Indicates a signal
Port2
Designated
port
Port4
Designated port
Proposing
Routing Switch 400
Routing Switch 60
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