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Changes in Behavior and Syntax


This section lists the changes in behavior of Junos OS features and changes in the syntax of Junos OS statements and commands in Junos OS Release 16.2R2 for the PTX Series.

General Routing

  • Support for deletion of static routes when the BFD session goes down (PTX Series)—Starting with Junos OS 16.2R2, the default behavior of the static route at the [edit routing-options static static-route bfd-admin-down] hierarchy level is active. So, the static routes are deleted when the BFD receives a session down message.

Interfaces and Chassis

  • Message now displayed when SIB autohealing is complete (PTX3000 and PTX5000)—Starting in Junos OS Release 16.2R2, the output of show chassis fabric errors autoheal displays a message when SIB autohealing is complete, as shown in the following example:


  • Support for status deprecated statement in YANG modules (PTX Series)—Starting with Junos OS Release 16.1R2, Juniper Networks YANG modules include the status deprecated statement to indicate configuration statements, commands, and options that are deprecated.

Network Management and Monitoring

  • Possible change to the object identifier (PTX Series)—Starting in Junos OS Release 16.2R2, the many warnings that occurred previously during MIB loading in the SNMP client has been reduced. This update could change the resulting OID depending on the SNMP client-loading logic. For example, jnxProductACX1000 is defined under the two following nodes:

    • jnxProductACX1000 OBJECT IDENTIFIER ::= { jnxProductVariationACX 1 }

    • jnxProductACX1000 OBJECT IDENTIFIER ::= { jnxProductVariationACX1000 1 }

    Because the second definition is the duplicate, it is removed. Previously, the SNMP client referred to the second OID based on MIB loading logic, and then you would see a change in OID for the client.

  • Improved usage of wildcard in SNMP notify-filter OID (PTX Series)—Starting in Junos OS Releases 13.3R10 and 16.2R2, the filter subtree using an asterisk (*) is correctly read as a wildcard and not as ASCII value of 42. The problem occurred in the following routers:

    • M Series running Junos OS Release 11.4R13.5, 13.3R7-S1

    • ACX2000 Series running Junos OS Release 12.3X54-D20.9

    • MX Series running Junos OS Release 14.1X50-D125

    A sample of the change appears in the output of the show snmp v3 command:

    Old Output

    New Output

  • Update to SNMP support of apply-path statement (PTX Series)—In Junos OS Release 16.2R2, SNMP implementation for the apply-path configuration statement supports only two lists:

    • apply-path "policy-options prefix-list <list-name> <*>"

      This configuration has been supported from day 1.

    • apply-path "access radius-server <*>"

      This configuration is supported as of this release.

  • Juniper MIBs Loading Errors Fixed (PTX Series)—In junos OS Release 16.2R1, duplicated entries and errors while loading MIBs on ManageEngine MIB browser are fixed for the following MIB files:

    • jnx-gen-set.mib

    • jnx-ifotn.mib

    • jnx-optics.mib

    [See MIB Explorer.]

  • SNMP syslog messages changed (PTX Series)—In Junos OS Release 16.2R2, two misleading SNMP syslog messages were rewritten to accurately describe the event:

    • OLD --AgentX master agent failed to respond to ping. Attempting to re-register

      NEW –- AgentX master agent failed to respond to ping, triggering cleanup!

    • OLD –- NET-SNMP version %s AgentX subagent connected

      NEW --- NET-SNMP version %s AgentX subagent Open-Sent!

    [See the MIB Explorer.]

Platform and Infrastructure

  • Improvements to MIB validation during Junos OS build (libjsnmp) (PTX Series)— Many warnings can be ignored if produced while MIBs are compiling. The following warnings should be considered as errors because they can break the build:

    [0-9]:.*failed to locateAn OID failed to be located.
    [0-9]:.*redefinition of identifierRedefinition of OIDs found in jnx-chas-defines.
    [0-9]:.*sequence-type-mismatchType mismatch found in sequence syntax of the table and actual OID type.
    [0-9]:.*cannot be imported from moduleMIB failed to import because order is not defined properly.

Routing Protocols

  • Change in default behavior of router capability (MX Series)—Starting in Junos OS Release 15.1F7, 16.1R4, 16.2R2, 16.1X65, and 17.1R1 and later, router capability TLV distribution flag (S-bit), which controls IS-IS advertisements, will be reset so that the segment routing capable sub-TLV is propagated throughout the IS-IS level and not advertised across IS-IS level boundaries.

System Logging

  • Changes in syslog MIB timeout messages (all routers and switches)—Starting in Junos OS Release 16.2, timeout messages logged in /var/log/messages for requests sent from snmpd to mib2d have changed:.

    • The frequency of AgentX timeout logs has been reduced.

      When a request sent from snmpd to mib2d times out, a timeout message is put in the messages log. Previously, one timeout message was written in the messages log for each such request, leading to flooding the log file with repetitive messages. Starting in Junos OS Release 16.2, one syslog message is created for all requests that time out at the same instant.

    • The “clearing the current stats” part in the logs has been removed.

      The timeout message has been changed because the subagents stats on timeout are no longer cleared. For example, the following is an old log message:

      Jul 11 20:56:50 re1-bx04.cbf14 snmpd[2436]: %-LIBJSNMP_NS_LOG_WARNING: WARNING: AgentX session, /var/run/mib2d-11, noticed request timeout. Clearing the current stats. Request PDUs: 1482, Response PDUs: 471, Request variables: 37186, Response variables: 11866, Average response time: 1826.42, Maximum response time: 40162.90

      New messages read as follows:

      Jul 16 10:32:30 Gladiator snmpd[2241]: %-LIBJSNMP_NS_LOG_WARNING: WARNING: AgentX session, /var/run/mib2d-11, noticed 3 request timeout.

      Jul 16 10:32:30 Gladiator snmpd[2241]: %-LIBJSNMP_NS_LOG_WARNING: WARNING: AgentX session, /var/run/mib2d-11, noticed 1 request timeout.

      Jul 16 10:32:30 Gladiator snmpd[2241]: %-LIBJSNMP_NS_LOG_WARNING: WARNING: AgentX session, /var/run/mib2d-11, noticed 1 request timeout.

User Interfaces and Configuration

  • Integers in configuration data in JSON format are displayed without quotation marks (PTX Series)—Starting in Junos OS Release 16.2R2, integers in Junos OS configuration data emitted in JavaScript Object Notation (JSON) format are not enclosed in quotation marks. Prior to Junos OS Release 16.2R2, integers in JSON configuration data were treated as strings and enclosed in quotation marks.

  • Changes to the XML and JSON output when displaying the differences between the candidate and active configurations (PTX Series)—Starting in Junos OS Release 16.2R2, when you compare the candidate and active configurations and display the differences in XML or JSON format, for example by using the show | compare | display (json | xml) CLI command or the <get-configuration compare="rollback" format="(json | xml)"> RPC, the device omits the <configuration> tag in the XML output and omits the configuration object in the JSON output if the comparison either returns no differences or if the comparison returns differences for only non-native configuration data, for example, configuration data associated with an OpenConfig data model.