Alcatel-Lucent 7750 SR - Page 666

Virtual Private LAN Services
Page 666 7750 SR OS Services Guide
max-age
Syntax max-age seconds
no max-age
Context config>service>vpls>stp
Description This command indicates how many hops a BPDU can traverse the network starting from the root
bridge. The message age field in a BPDU transmitted by the root bridge is initialized to 0. Each other
bridge will take the message_age value from BPDUs received on their root port and increment this
value by 1. The message_age thus reflects the distance from the root bridge. BPDUs with a message
age exceeding max-age are ignored.
STP uses the max-age value configured in the root bridge. This value is propagated to the other
bridges via the BPDUs.
The no form of this command returns the max ageto the default value.
Default 20 seconds
Parameters seconds — The max info age for the STP instance in seconds. Allowed values are integers in the
range 6 to 40.
mode
Syntax mode {rstp | comp-dot1w | dot1w | mstp | pmstp}
no mode
Context config>service>vpls>stp
Description This command specifies the version of Spanning Tree Protocol the bridge is currently running.
See section Spanning Tree Operating Modes on page 435 for details on these modes.
The no form of this command returns the STP variant to the default.
Default rstp
Parameters rstp — Corresponds to the Rapid Spanning Tree Protocol specified in IEEE 802.1D/D4-2003.
dot1w — Corresponds to the mode where the Rapid Spanning Tree is backward compatible with
IEEE 802.1w.
compdot1w — Corresponds to the Rapid Spanning Tree Protocol fully conformant to IEEE 802.1w.
mstp — Sets MSTP as the STP mode of operation. Corresponds to the Multiple Spanning Tree
Protocol specified in 802.1Q REV/D5.0-09/2005
pmstp — The PMSTP mode is only supported in VPLS services where the mVPLS flag is
configured.