udld mode

Syntax

udld mode aruba-os {verify-then-forward | forward-then-verify}

udld mode rfc5171 <RFC5171-MODE>

no udld mode

Description

Sets the operating mode.

The no form of this command sets the operating mode to the default value of aruba-os and forward-then-verify.

Command context

config-if

Parameters

aruba-os {verify-then-forward | forward-then-verify}

Selects the ArubaOS mode to use. Use this mode when interconnecting with HPE PVOS/Brocade/Foundry switches.

verify-then-forward
In this mode:
  • Interfaces start as unblocked.

  • Once an interface is determined to be bidirectional, it is blocked if the retry limit is reached without receiving any UDLD packets.

  • Interfaces automatically unblock if a UDLD packet is received.

  • On failover, the UDLD state does not change if the (interval * retries) time is around 6 seconds.

forward-then-verify
In this mode:
  • Interfaces start as unblocked.

  • Interfaces transition to the unblocked state when receiving UDLD packets.

  • Once an interface is determined to be bidirectional, it is blocked if the retry limit is reached without receiving any UDLD packets.

  • Interfaces automatically unblock if a UDLD packet is received.

rfc5171 <RFC5171-MODE>

Selects the RFC5171 mode to use. Use this mode when interconnecting with third-party switches.

normal
In this mode:
  • Interfaces start as unblocked.

  • Interfaces do not block when the retry limit is reached without receiving any UDLD packets (plus 8 extra packets sent to the peer). Instead, an event is generated.

  • Interfaces automatically unblock if a UDLD packet is received.

aggressive
In this mode:
  • Interfaces start as unblocked.

  • Once an interface is determined to be bidirectional, an interface will block when the retry limit is reached without receiving any UDLD packets (plus 8 extra packets sent to the peer).

  • Interfaces implement a limited/reduced errDisabled recovery mechanism. When the interface's state goes to errDisabled, a maximum of 3 attempts (5 minutes apart) are triggered to try and bring up the interface in case the remote endpoint is still sending UDLD packets. After these 3 retries, the interface will remain blocked even if UDLD packets are received. The only way to unblock the interface when this occurs is to disable (and optionally re-enable) UDLD on the interface. The retry limit is reset once the interface becomes unblocked.

Authority

Administrators or local user group members with execution rights for this command.

Examples

Setting the operating mode to aruba-os and forward-then-verify on interface 1/1/1:

switch(config)# interface 1/1/1
switch(config-if)# udld mode aruba-os forward-then-verify

Setting the operating mode to rfc5171 and aggressive on interface 1/1/1:

switch(config)# interface 1/1/1
switch(config-if)# udld mode rfc5171 aggressive

Setting the operating mode on interface 1/1/1 to the default value:

switch(config)# interface 1/1/1
switch(config-if)# no udld mode