DELL 9.7(0.0) User Manual
To ensure that existing network applications see no difference when a primary interface in a redundant
pair transitions to the backup interface, be sure to apply identical configurations of other traffic
parameters to each interface.
pair transitions to the backup interface, be sure to apply identical configurations of other traffic
parameters to each interface.
If you remove an interface in a redundant link (remove the line card of a physical interface or delete a
port channel with the no interface port-channel command), the redundant pair configuration is
also removed.
port channel with the no interface port-channel command), the redundant pair configuration is
also removed.
Important Points about Configuring Redundant Pairs
• You may not configure any interface to be a backup for more than one interface, no interface can
have more than one backup, and a backup interface may not have a backup interface.
• The active or backup interface may not be a member of a LAG.
• The active and standby do not have to be of the same type (1G, 10G, and so on).
• You may not enable any Layer 2 protocol on any interface of a redundant pair or to ports connected
• The active and standby do not have to be of the same type (1G, 10G, and so on).
• You may not enable any Layer 2 protocol on any interface of a redundant pair or to ports connected
to them.
As shown in the previous illustration, interface 3/41 is a backup interface for 3/42, and 3/42 is in the
Down state. If 3/41 fails, 3/42 transitions to the Up state, which makes the backup link active. A message
similar to the following message appears whenever you configure a backup port.
02:28:04: %SYSTEM-P:CP %IFMGR-5-L2BKUP_WARN: Do not run any Layer2 protocols on
Down state. If 3/41 fails, 3/42 transitions to the Up state, which makes the backup link active. A message
similar to the following message appears whenever you configure a backup port.
02:28:04: %SYSTEM-P:CP %IFMGR-5-L2BKUP_WARN: Do not run any Layer2 protocols on
Te 3/41
and Te 3/42
02:28:04: %SYSTEM-P:CP %IFMGR-5-OSTATE_DN: Changed interface state to down: Te
3/42
02:28:04: %SYSTEM-P:CP %IFMGR-5-STATE_ACT_STBY: Changed interface state to
standby: Te
3/42
Example of Configuring Redundant Layer 2 Pairs
Dell(conf-if-range-te-3/41-42)#switchport backup interface TengigabitEthernet
Dell(conf-if-range-te-3/41-42)#switchport backup interface TengigabitEthernet
3/42
Dell(conf-if-range-te-3/41-42)#show config
!
interface TengigabitEthernet 3/41
no ip address
switchport
switchport backup interface TengigabitEthernet 3/42
no shutdown
!
interface TengigabitEthernet 3/42
no ip address
switchport
no shutdown
Dell(conf-if-range-te-3/41-42)#
Dell(conf-if-range-te-3/41-42)#do show ip int brief | find 3/41
TengigabitEthernet 3/41 unassigned YES Manual up up
TengigabitEthernet 3/42 unassigned NO Manual up down
[output omitted]
Dell(conf-if-range-te-3/41-42)#interface tengig 3/41
Dell(conf-if-te-3/41)#shutdown
00:24:53: %SYSTEM-P:CP %IFMGR-5-ASTATE_DN: Changed interface Admin state to
down: Te 3/41
Dell(conf-if-te-3/41)#00:24:55: %SYSTEM-P:CP %IFMGR-5-OSTATE_DN: Changed
interface state to
down: Te 3/41
00:24:55: %SYSTEM-P:CP %IFMGR-5-INACTIVE: Changed Vlan interface state to
inactive: Vl 1
00:24:55: %SYSTEM-P:CP %IFMGR-5-OSTATE_UP: Changed interface state to up: Te
Layer 2
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