Logical Interfaces

VLAN Interface

Please refer to VLAN.

LAG Interface

Please refer to LAG .

Sub-interface

Sub-interface Status View

Table 1 Sub-interface Status View

Command	Purpose
show sub-interface [ethernet interface_name.subinterface-number]	Display information about the status of subinterfaces.
show {ip\|ipv6} interfaces	Display IP address configuration of subinterfaces.

show sub-interface [ethernet interface_name.subinterface-number]

[Command]

show sub-interface [ethernet interface_name.subinterface-number]

[Purpose]

Display information about the status of subinterfaces.

[Parameters]

Parameter	Description
interface_name	Parent interface name. (eg.0/1)
subinterface-number	Subinterface number.

[View]

Privileged User View

[Use Cases]

sonic# show sub-interface
  Sub port interface    Speed    MTU    vlan    Admin                  Type
--------------------  -------  -----  ------  -------  --------------------
              0/0.2       25G   9100       2       up  802.1q-encapsulation

show {ip|ipv6} interfaces

[Command]

show {ip|ipv6} interfaces

[Purpose]

Display IP address configuration of subinterfaces.

[View]

Privileged User View

[Use Cases]

sonic# show ip interfaces
Interface    Master    IPv4 address/mask    Admin/Oper    BGP Neighbor    Neighbor IP
-----------  --------  -------------------  ------------  --------------  -------------
0/0.2                  2.0.0.1/24           up/down       N/A             N/A
0/48                   199.0.3.1/24         up/up         N/A             N/A
0/52                   199.0.7.1/24         up/up         N/A             N/A
loopback0              10.1.0.34/32         up/up         N/A             N/A
mgmt                   10.250.0.138/24      up/up         N/A             N/A

Sub-interface Config

Table 2 Subinterface Config

Command	Purpose
interface {ethernet\|link-aggregation} interface_name.subinterface-number	Create a subinterface.
mtu mtu	Configure the MTU value on a subinterface.
shutdown	Bring the subinterface down administratively.
ip address {A.B.C.D/M\|A::B/M} [secondary]	Configure IP address for the subinterface.
mac_address HH:HH:HH:HH:HH:HH	Specify a MAC address to the subinterface.

interface {ethernet|link-aggregation} interface_name.subinterface-number

[Command]

interface {ethernet|link-aggregation} interface_name.subinterface-number

[Purpose]

Create a subinterface.

[Parameters]

Parameter	Description
interface_name	Parent interface name. (eg.0/1)
subinterface-number	Subinterface number.

[View]

Global Configuration View

[Notes]

Run command no interface {ethernet|link-aggregation} interface_name.subinterface-number to delete the subinterface.

[Use Cases]

sonic# configure terminal
sonic(config)# interface ethernet 0/1.1
sonic(config-if-0/1.1)# show this
!
interface ethernet 0/1.1
sonic(config)# no interface ethernet 0/1.1

mtu mtu

[Command]

mtu mtu

[Purpose]

Configure the MTU value on a subinterface.

[Parameters]

Parameter	Description
mtu	Maximum Transmission Unit, the range is from 1312 to 9216. The default is 9216 Bytes.

[View]

Subinterface Configuration View

[Use Cases]

sonic# configure terminal
sonic(config)# interface ethernet 0/1.1
sonic(config-if-0/1.1)# mtu 2000
sonic(config-if-0/1.1)# show this
!
interface ethernet 0/1.1
 mtu 2000

shutdown

[Command]

shutdown

[Purpose]

Bring the subinterface down administratively.

[View]

Subinterface Configuration View

[Notes]

Run command no shutdown to bring the sub-interface up administratively.

[Use Cases]

sonic# configure terminal
sonic(config)# interface ethernet 0/1.1
sonic(config-if-0/1.1)# shutdown
sonic(config-if-0/1.1)# show this
!
interface ethernet 0/1.1
 shutdown

ip address {A.B.C.D/M|A::B/M} [secondary]

[Command]

ip address {A.B.C.D/M|A::B/M} [secondary]

[Purpose]

Configure IP address for the subinterface.

[Parameters]

Parameter	Description
A.B.C.D/M	IPv4 address with prefix length.
A::B/M	IPv6 address with prefix length.
secondary	The default is Primary IP, specifying this option means configuring as Secondary IP, which requires that the Secondary IP and Primary IP be in the same network segment.

[View]

Subinterface Configuration View

[Notes]

IPv4 address with subnet mask /32 is not allowed to be configured. Addresses with subnet mask /31 is allowed. In other subnet masks, addresses with the host portion all-zeros or all-ones are not allowed. IPv6 address with subnet mask /127 or /128 is not allowed to be configured. In other subnet masks, addresses with the host portion all-zeros are not allowed, but all-ones are allowed. Run command no ip address {A.B.C.D/M|A::B/M} [secondary]to delete IP address configuration of the subinterface.

[Use Cases]

sonic# configure terminal
sonic(config)# interface ethernet 0/2.2
sonic(config-if-0/2.2)# ip address 3.3.3.6/24
sonic(config-if-0/2.2)# show this
!
interface ethernet 0/2.2
ip address 3.3.3.6/24

mac_address HH:HH:HH:HH:HH:HH

[Command]

mac_address HH:HH:HH:HH:HH:HH

[Purpose]

Specify a MAC address to the subinterface.

[Parameters]

Parameter	Description
HH:HH:HH:HH:HH:HH	MAC address, not case sensitive.

[View]

Subinterface Configuration View

[Notes]

The default is the MAC of the switch. Run command no mac_address to restore the MAC of the sub-interface to default.

[Use Cases]

sonic# configure terminal
sonic(config)# interface ethernet 0/2.2
sonic(config-if-0/2.2)# mac-address 18:17:25:37:67:af
sonic(config-if-0/2.2)# show this
!
interface ethernet 0/2.2
 mac-address 18:17:25:37:67:af

Loopback

Loopback View

Table 3 Loopback View

Command	Purpose
show {ip\|ipv6} interfaces	Display IP address configuration of loopback interfaces.

show {ip|ipv6} interfaces

[Command]

show {ip|ipv6} interfaces

[Purpose]

Display IP address configuration of loopback interfaces.

[View]

Privileged User View

[Use Cases]

sonic# show ip interfaces
Interface    Master    IPv4 address/mask    Admin/Oper    BGP Neighbor    Neighbor IP
-----------  --------  -------------------  ------------  --------------  -------------
0/48                   199.0.3.1/24         up/up         N/A             N/A
0/52                   199.0.7.1/24         up/up         N/A             N/A
0/72                   10.72.0.1/24         up/up         N/A             N/A
loopback0              10.1.0.34/32         up/up         N/A             N/A
mgmt                   10.250.0.138/24      up/up         N/A             N/A

Loopback Config

Table 4 Loopback Config

Command	Purpose
interface loopback loopback-id	Enter Loopback Interface Configuration View.
ip address {A.B.C.D/M\|A::B/M}	Configure IP address for the loopback interface.

interface loopback loopback-id

[Command]

interface loopback loopback-id

[Purpose]

Enter Loopback Interface Configuration View

[Parameters]

Parameter	Description
loopback-id	Loopback interface number, integer form, range from 0 to 999.

[View]

Global Configuration View

[Notes]

Loopback0 has been created by default and cannot be deleted. Run command no interface loopback loopback-id to delete loopback interface.

[Use Cases]

sonic# configure terminal
sonic(config)# interface loopback 1
sonic(config-loif-1)# show this
!
interface loopback 1

ip address {A.B.C.D/M|A::B/M}

[Command]

ip address {A.B.C.D/M|A::B/M}

[Purpose]

Configure IP address for the loopback interface.

[Parameters]

Parameter	Description
A.B.C.D/M	IPv4 address with prefix length.
A::B/M	IPv6 address with prefix length.

[View]

Loopback Interface Configuration View

[Notes]

Run command no ip address {A.B.C.D/M|A::B/M} to delete IP address configuration of the loopback interface.

[Use Cases]

sonic# configure terminal
sonic(config)# interface loopback 2
sonic(config-loif-2)# ip address 3.3.3.6/24
sonic(config-loif-2)# show this
!
interface loopback 2
ip address 3.3.3.6/24