Technical data

Switching and Routing
May 2012 © 2012 Brocade Communications Systems, Inc. 2 - 3
NOTE: The information displayed in columns with headings CamF, and CIDX0 through CIDX5, is not relevant for
day-to-day management of the ServerIron. The information is used by engineering and technical support staff for
debug purposes.
Syntax: show mac-address [ethernet <portnum> | <mac-addr> | session]
The session keyword causes information about MAC session entries to be displayed.
Displaying MAC Address Statistics
To display the total number of MAC addresses currently active on a ServerIron, enter the following command:
For each port, the number of learned MAC addresses is displayed.
Syntax: show mac-address-statistics
This command serves as a numerical summary of the detailed summary provided by the command show mac-
addresses.
STP
The Spanning Tree Protocol (STP) detects and eliminates logical loops in a Layer 2 broadcast domain. STP is
described in the IEEE 802.1d bridge protocols standard and ensures the device uses the most efficient path when
multiple paths exist between ports. If a selected path fails, STP searches for and then establishes an alternate
path to prevent or limit retransmission of data.
For ServerIron devices, STP is disabled by default on Router (R) code images but enabled by default on the
Switch (S) code images.
Configuring Fast Port Span
The Fast Port Span feature allows faster STP convergence on ports that are attached to end stations. To configure
this feature, enter the following command:
ServerIron(config)#fast port-span
To exclude a port from Fast Port Span, while leaving Fast Port Span enabled globally, enter the following
command:
ServerIron(config)#fast port-span exclude ethernet 1
Syntax: [no] fast port-span [exclude ethernet <portnum> [ethernet <portnum>… | to <portnum>]
Configuring Fast Uplink Span
The Fast Uplink Span feature reduces the convergence time for uplink ports to another device to just four seconds
(two seconds for listening and two seconds for learning). To configure this feature, enter the following command:
ServerIron(config)# fast uplink-span ethernet 1 to 4
Syntax: [no] fast uplink-span [ethernet <portnum> [ethernet <portnum>… | to <portnum>]
ServerIron(config)# show mac-address-statistics
Total entries = 41
Port 1 2 3 4 5 6 7 8 9
0 6 11 1 1 1 2 1 1
Port 10 11 12 13 14 15 16
0 3 1 3 1 1 8