Specifications

2-476
Catalyst 4500 Series Switch Cisco IOS Command Reference—Release IOS XE 3.3.0XO(15.1(1)XO)
OL_28738 -01
Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
rep block port
rep block port
Use the rep block port interface configur ation comm and on the REP primary e dge port to c onfigure
Resilient Ethernet Protocol (REP) VLAN load balancing. Use the no form of this command to return to
the default configuration.
rep block port {id port-id | neighbor_offset | preferred} vlan {vlan-list | all}
no rep block port {id port-id | neighbor_offset | preferred}
Syntax Description
Defaults T he defaul t behavior after you ente r the rep preempt segment privileged EXEC command (for manual
preemption) is to block all VLANs at the pr imary edge port. This behavior r emains until you configu re
the rep block port command.
If the primary edge port cannot determine which port is to be the alternate port, the default action is no
preemption and no VLAN load balancing.
Command Modes Interface configur ation
Usage Guidelines You must enter this command on the REP primary edge port.
When you select an alternate port by entering an offset numbe r, this number identifies th e downstream
neighbor port of an edge port. The primary edge port has an offset number o f 1; positive numbers above
1 identify downstream neighbo rs of the primary edge port . Negative numbers identif y the secondary
edge port (offset number -1) and its downstream neighbor s. See Neighbor Offset Numbers in a REP
SegmentFigure 2-2.
id port-id Identify the VLAN blocking alternate port by entering the unique port ID that is
automatically generated when REP is enabled. The REP port ID is a 16-character
hexadecimal value. You can view the port ID for an interface by entering the show
interface interface-id rep detail command.
neighbor_offset Identify the VLAN blocki ng alternate port by entering the offset number of a
neighbor. The range is –2 56 to +256; a value of 0 is inval id. The pri mary edge po rt
has an offset number of 1; positive numbers a bove 1 identify downstream
neighbors of the primar y edge port . Negative numb ers ident ify the se condary edge
port (offset number -1) and its downstrea m neigh bors.
preferre d Identify the VLAN blocking alte rnate port as the segment port on which you
entered the rep se gmen t segment-id pref e rred interface configuration command.
Note Entering the preferred keyword does not e nsure t hat t he prefe rred po rt is
the alternate port; it gives it preference over other similar ports.
vlan Identify the VLANs to be blocked.
vlan-list Ente r a VLAN ID from 1 to 4094 or a range or sequence of VLANs (such as 1-3,
22, 41-44) of VLANs to be blocked.
all Enter to bloc k all VLANs.