Users Guide

Loopback interfaces
A Loopback interface is a virtual interface where the software emulates an interface. Because a Loopback interface is not
associated to physical hardware entities, the Loopback interface status is not affected by hardware status changes.
Packets routed to a Loopback interface process locally to the OS10 device. Because this interface is not a physical interface, to
provide protocol stability you can configure routing protocols on this interface. You can place Loopback interfaces in default L3
mode.
● Enter the Loopback interface number in CONFIGURATION mode, from 0 to 16383.
interface loopback number
● Enter the Loopback interface number to view the configuration in EXEC mode.
show interface loopback number
● Enter the Loopback interface number to delete a Loopback interface in CONFIGURATION mode.
no interface loopback number
View Loopback interface
OS10# show interface loopback 4
Loopback 4 is up, line protocol is up
Hardware is unknown.
Interface index is 102863300
Internet address is 120.120.120.120/24
Mode of IPv4 Address Assignment : MANUAL
MTU 1532 bytes
Flowcontrol rx false tx false
ARP type: ARPA, ARP Timeout: 240
Last clearing of "show interface" counters : 00:00:11
Queuing strategy : fifo
Input 0 packets, 0 bytes, 0 multicast
Received 0 errors, 0 discarded
Output 0 packets, 0 bytes, 0 multicast
Output 0 errors, Output 0 invalid protocol
Time since last interface status change : 00:00:11
Port-channel interfaces
Port-channels are not configured by default. Link aggregation (LA) is a method of grouping multiple physical interfaces into a
single logical interface — a link aggregation group (LAG) or port-channel. A port-channel aggregates the bandwidth of member
links, provides redundancy, and load balances traffic. If a member port fails, the OS10 device redirects traffic to the remaining
ports.
A physical interface can belong to only one port-channel at a time. A port-channel must contain interfaces of the same interface
type and speed. OS10 supports a maximum of 128 port-channels, with up to thirty-two ports per channel.
To configure a port-channel, use the same configuration commands as the Ethernet port interfaces. Port-channels are
transparent to network configurations and manage as a single interface. For example, configure one IP address for the group,
and use the IP address for all routed traffic on the port-channel.
By configuring port channels, you can create larger capacity interfaces by aggregating a group of lower-speed links. For
example, you can build a 40G interface by aggregating four 10G Ethernet interfaces together. If one of the four interfaces fails,
traffic redistributes across the three remaining interfaces.
Static
Port-channels are statically configured.
Dynamic Port-channels are dynamically configured using Link Aggregation Control Protocol (LACP).
Member ports of a LAG are added and programmed into the hardware based on the port ID, instead of the order the ports come
up. Load balancing yields predictable results across resets and reloads.
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Interfaces