Technical data

BLADE OS 5.0 Command Reference
226
 Chapter 6: The Configuration Menu BMD00142, November 2009
/cfg/l2/mrst/cist/port <port alias or number>
CIST Port Configuration
CIST port parameters are used to modify MRST operation on an individual port basis. CIST
parameters do not affect operation of STP/PVST+, RSTP, or PVRST. For each port, RSTP/MSTP is
turned on by default.
[CIST Port 1 Menu]
prior - Set port Priority (0-240)
cost - Set port Path Cost (1-200000000, 0 for auto)
hello - Set CIST port Hello Time (1-10 secs)
link - Set MSTP link type (auto, p2p, or shared; default: auto)
(for MSTP only)
pvst-pro - Enable/disable PVST Protection (for MSTP only)
on - Turn port's Spanning Tree ON
off - Turn port's Spanning Tree OFF
cur - Display current port Spanning Tree parameters
Table 124 CIST Port Configuration Options
Command Syntax and Usage
prior <0-240>
Configures the CIST port priority. The port priority helps determine which bridge port
becomes the designated port. In a network topology that has multiple bridge ports connected
to a single segment, the port with the lowest port priority becomes the designated port for the
segment. The range is 0 to 240, in steps of 16 (0, 16, 32...), and the default is 128.
cost <0-200000000>
Configures the CIST port path cost. The port path cost is used to help determine the
designated port for a segment. Port path cost is based on the port speed, and is calculated as
follows:
 1Gbps = 20000
 10Gbps = 2000
The default value of 0 (zero) indicates that the default path cost will be computed for an auto
negotiated link speed.
hello <1-10 seconds>
Configures the CIST port Hello time.The Hello time specifies how often the root bridge
transmits a configuration bridge protocol data unit (BPDU). Any bridge that is not the root
bridge uses the root bridge Hello value. The range is 1 to 10 seconds, and the default is 2
seconds.