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Known Limitations

Learn about known limitations in this release for MX Series routers.

For the most complete and latest information about known Junos OS defects, use the Juniper Networks online Junos Problem Report Search application.

General Routing

  • In a scaled setup with LDP over RSVP configuration and maximum-ecmp as 32 or 64, line card CPU usage can remain high for extended duration on link flap operation. In this duration, LACP might take 5 minutes or more to converge and the aggregated Ethernet interface bundle to be active. PR1624219

  • The SDN-Telemetry process might crash during long running streaming telemetry collectors. Telemetry data loss occurs streamed from the line cards till the process comes up. PR1647568

  • If proper gap is given between channelisation and dechannelisation the issue is not seen. Proper gap means allowing the system to complete the previous config before we load the new configuration. Recommendation is to if we give channelisation config commit wait for the links to come up or atleast the ifd's get created on both evo and RE side and then only revert the configuration to dechannlisation and vice versa. PR1665625

  • VM host snapshot recovery is not enabled for RE-S-X6-128G-K. PR1674091

  • Even though GRES is enabled, the show system filesystem encryption status command display information about the specific Routing Engine. PR1674373

  • For IPv6 traffic that is ingressing into an Abstract Fabric (AF) interface via MPC11e card, and also sampled, the OutputIntf in the flow records might not be captured if you do not enable the nexthop-learning command. PR1680873

  • MVRP on PVLAN promiscous port is not supported. If you configure MVRP on promiscous port, then hosts connected to secondary VLAN ports will not be able to reach external world through promiscous port carrying primary VLAN tags. PR1693345


  • With local reversion on, there is a possibility of transit router not informing headend of RSVP disabled link when the link flaps more than once. As a workaround, remove the local-reversion configuration. PR1576979

Network Management and Monitoring

  • Junos might translate the custom yang configuration even after disabling the custom Yang package. PR1599107

Platform and Infrastructure

  • On MX devices, under Ethernet VPN (EVPN) environment, packets routed using IRB interface could not be fragmented due to media maximum transmission unit (MTU) problem. PR1522896

  • When the deactivate services rpm and deactivate routing-options rpm-tracking commands are applied together and then committed, some of the rpm tracked added routes are not deleted from the routing table. Issue cannot be seen using the following steps:

    1. Deactivate routing-options rpm-tracking .

    2. Commit the configuration then all the rpm tracked routes will be deleted. If the RPM service needs to be deactivated.

    3. Deactivate services rpm.

    4. Commit.

  • On MX platforms, VPLS flood traffic loss is observed if flood composite next-hops are out-of-sync on ingress and egress FPCs during transport path revertion. PR1656216

Routing Protocols

  • When you do not configure routing-options transport-class fallback none, you cannot configure more than 10 transport-classes or advertise more than 10 distinct colors in SRTE or FlexAlgo. PR1648490

Services Applications

  • In Junos OS release 17.4 and later, subscriber sessions on the LNS that send an ICRQ that includes RFC5515 AVPs might fail to establish a session. The client might receive a receive-icrq-avp-missing-random-vector CDN error in response. PR1493289