Reference Guide

Parameters
stp-id Enter the STP instance ID. The range is 0.
cost cost Enter the keyword cost followed by a number as the cost.
The range is 1 to 65535. The defaults are:
• 100 Mb/s Ethernet interface = 19.
• 1-Gigabit Ethernet interface = 4.
• 10-Gigabit Ethernet interface = 2.
• Port Channel interface with 100 Mb/s Ethernet = 18.
• Port Channel interface with 1-Gigabit Ethernet = 3.
• Port Channel interface with 10-Gigabit Ethernet = 1.
loopguard (C-, S-, and E-Series TeraScale and S4810 only) Enter the
keyword loopguard to enable STP loop guard on a port or
port-channel interface.
rootguard (C-, S-, and E-Series TeraScale and S4810 only) Enter the
keyword rootguard to enable STP root guard on a port or
port-channel interface.
portfast
[bpduguard
[shutdown-on-
viol ation]]
Enter the keyword portfast to enable Portfast to move the
interface into Forwarding mode immediately after the root
fails.
Enter the optional keyword bpduguard to disable the port
when it receives a BPDU.
Enter the optional keyword shutdown-on-violation to
hardware disable an interface when a BPDU is received and
the port is disabled.
priority priority Enter keyword priority followed by a number as the
priority. The range is zero (0) to 15. The default is
8.
Defaults cost = depends on the interface type; priority = 8
Command
Modes
INTERFACE
Command
History
Version 8.3.10.1 Introduced the loopguard and rootguard options on the
S4810.
Version 8.4.2.1 Introduced the loopguard and rootguard options on the
E-Series TeraScale, C-Series, and S-Series.
Version 8.3.7.0 Introduced on the S4810.
Version 8.2.1.0 Introduced the shutdown-on-violation option.
Version 7.7.1.0 Introduced on the S-Series.
Version 7.5.1.0 Introduced on the C-Series.
1948
Spanning Tree Protocol (STP)