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JUNOS 16.1 or later - MPLS LSP related configuration changes

  [TSB17237] Show Article Properties

Alert Type:
PSN - Product Support Notification
Product Affected:
All products running JUNOS 16.1 or later using MPLS LSPs
Alert Description:
MPLS LSP "self-ping" is a new feature and is enabled by default in JUNOS 16.1 or later. This PSN emphasizes necessary steps that you need to take to make sure of successful upgrade.

In summary

  • LSP self-ping is on by default starting with JUNOS 16.1R1
  • LSP self-ping relies on sending UDP datagram with destination port 8503 (IPv4 and IPv6 as needed). If there is a loopback filter, you need to allow UDP destination port 8503 to get through your loopback filter
  • Since Circuit Cross-Connect (CCC) LSPs is neither IPv4 nor IPv6, LSP self-ping is not supported on such LSPs. Hence, you need to turn off LSP self-ping for these LSPs using the following configuration:

WARNING:  PR1303798 In a rare circumstance, a device may experience a restart after upgrading its software to JUNOS software version with self-ping enabled. The contributing factor to the restart is applicable to all platforms. However, it has been mostly seen on a 32-bit system such as a QFX5100 or when forcing RPD to run in 32-bit mode via "set system process routing force-32-bit" configuration command.

Modification History:
Update on 2019-03-08
  • Fixing grammar mechanic
  • Publishing this to the public on 2019-03-08
First publication date is 2017-12-13
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