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Open Issues

Learn about open issues 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.

Class of Service (CoS)

  • On the MPC7E line cards, the BPS counter of the egress queue displays wrong BPS value when the cell mode is configured on the static interface. PR1568192


  • The VXLAN OAM host-bound packets are not throttled with the DDoS policers. PR1435228

  • The vmcore process generates core file at rts_ifbd_get_parent, rts_ifstate_chk_if_interesting_int, rts_ifstate_chk_if_interesting_int_with_stats. PR1542037

  • Prefix added to the mhevpn.evpn.0 output route table triggers TC failure. PR1566429

  • The mustd.core process generates core file during upgrading or committing a configuration. PR1577548

  • On the MX480 routers, the vmcore process generates core file at rts_ifbd_get_parent, rts_ifstate_chk_if_interesting_int, rts_ifstate_chk_if_interesting_int_with_stats. PR1580313

  • The rpd process might crash if the EVPN routing instances or BGP connections flaps. PR1581674

  • Multicast traffic loss occurs in the EVPN setup with IGMP Snooping used. PR1582134

  • After configuring flexible-cross-connect-vlan-unaware in the Virtual private wire service (VPWS), routing instances observes circuit cross-connect interface in the dscd state on the primary PE devices. PR1585027

Forwarding and Sampling

  • Packet length for ICMPv6 is shown as 0 in the output of the show firewall log detail command. PR1184624

  • After you restart routing, the remote mask (which indicates from which remote PE devices MAC-IP addresses are learned) that the routing daemon sends might be different from the existing remote mask that the Layer 2 learning daemon had before the restart. This causes a mismatch between Layer 2 learning and routing daemons' interpretation as to where the MAC-IP address entries are learned, either local or remote, leading to the MAC-IP table being out of synchronization. PR1452990

General Routing

  • On the MX104 router, if you use snmpbulkget or snmpbulkwalk (for example, used by the SNMP server) on a chassisd-related component (for example, jnxOperatingEntry), high CPU usage and slow response of the chassis process (chassisd) might be observed because of a hardware limitation, which might also lead to a query timeout on the SNMP client. This issue might not be observed while using an SNMP query. PR1103870

  • On the MPC7E line cards, the following log message might be seen on FPC with WINTEC mSATA SSD:

  • Modifying the underlying interface on a demux0 interface with subscribers present on the underlying interface causes the FPC to generate core files. PR1396157

  • Subscribers experience 100 percent CPU utilization of the FPC for 56 minutes after changing the service firewall filter configuration. PR1447003

  • In the DNS filtering when the DNS request are sent from the server, implicit filters and routes to the service PIC are configured. This causes the DNS packets to loop. PR1468398

  • A regression issue causes the WAN-PHY interface to continuously flap with the default hold-time down of 0. PR1508794

  • LFM might flap during MX Virtual Chassis ISSU. PR1516744

  • The RPD sensors generate core files during defer-continue case on the network churn. PR1526503

  • Inconsistent core.python2.7.mpc0 core file is seen with stacktrace @ea_wi_precl,@ea_macsec_receive.PR1534568

  • The CFM sessions go down during FRU upgrade stage of ISSU in MX Virtual Chassis. PR1534628

  • On the MX480 routers, sFlow log error message is seen when egress sampling is enabled in a dynamic IP-IP tunnel encapsulation scenario. PR1538863

  • On the MX2020 router, the next hops are less than the total number of nhdb 4MPOST GRES. PR1539305

  • Even though enhanced-ip is active, the following alarm is observed during ISSU: PR1546002
  • Heap malloc(0) is detected for jnh_unilist_adaptive_add on loading the configurations. PR1547240

  • Commit error is observed when deactivate chassis synchronization source and esmc-transmit all are configured. PR1549051

  • Captive portal for phone-home bootstrap process is not supported. PR1555112

  • On the MPC11E line cards in BSYS, commit goes through when ISSU is initiated in the GNF. PR1556544

  • On the MX10008 routers, the GRE keepalive adjacency state is Down even though the GRE tunnel is in the Up state. PR1559200

  • On the MPC11 line cards, error messages are not displayed while executing the show log message command with errors. PR1560920

  • Core files are found at MX104-ABB-0.gz.core.0.gz >clksync_geneva_delete_ptp_loc_entry> clksync_geneva_ptp_add_clock_entry> clksync_ptp_stream_proc_op> clksync_event_update> clksync_process_event. PR1561004

  • The session status gets stuck in the Invalid state after the core-facing link fails in the primary PE devices. PR1562387

  • Fusion cascade ports must not be hosted on the VPN core-facing FPC. PR1567850

  • On the MX480 routers, traffic loss is observed with scale 4000 tunnels 800 VRF test. PR1568414

  • Sometimes part of the output of the show ptp lock-status detail command is missed while changing the interface configuration from the encapsulation Ethernet to the family inet. PR1572047

  • PIM rib-group fails to be added in VRF. PR1574497

  • Commit check for a validating the interface name is not available for the show interface command. PR1306191

  • Changing the scaled firewall profiles on the fly does not release the TCAM resources as expected. PR1512242

  • MACSEC PIC stays offline in new primary after ISSU is in GNF. PR1534225

  • the ngmpc2 process generates core file at bv_entry_active_here::bv_vector_op:: gmph_reevaluate_group:: gmph_destroy_client_group. PR1537846

  • During power cycle, 100G port down issue is observed occasionally on et-0/0/54 and et-0/0/55 with INNOLIGHT 100G-AOC cables. PR1548525

  • On the MPC9E line card, core file is generated when SFB is online after ISSU of a GNF.


  • The core.python2.7.mpc0 core file is observed while trying to integrate script in vZT. PR1556719

  • RIOT crashes with the following error message that causes aftd-trio crash: FATAL:Failed to translate ucode instruction. PR1559522

  • IGMP joins where there are more than expected value while verifying the IGMP snooping membership in the CE router. PR1560588

  • Some BFD sessions get stuck in the Down or Init state after the iterative operations triggers on DUT. PR1560772

  • The traffic silently gets discarded on switching the rlt interface with both legs on subLC slices. PR1566198

  • After loading the inline services configuration and loading the twamp configuration, the SLC reboots and AFT generates core files. PR1567313

  • The mpc-2e-3e-ng core file is generated at htimer_is_last_child htimer_relink_timer htimer_set_exptime_internal. PR1567495

  • The mspmand process might crash if the packet flow-control issue occurs on MS-MPC or MS-MIC. PR1569894

  • PDB pull or synchronization does not occur in new primary during ISSU. PR1570841

  • The toe_gld_toe0_ucode process generates core file at prds_rt_ifl_ipv6_del_hndl_from_desc_list.PR1571279

  • The show services mobile-edge sessions summary access-network-peers command displays incorrect established subscriber output after the UPF Handover ENB step. PR1572520

  • The unplugged message of the CFP is not logged in Junos OS Release 17.3 and later. PR1573209

  • The rpd process on the transit node might crash while performing the MPLS traceroute on the ingress node. PR1573517

  • From the regress user shell prompt, the vhclient access does not display the following error: rcmd: socket: Operation not permitted. PR1574240

  • The MPC10E line cards generates the following error message: user.err aftd-trio: [Error] Em: root: Insert entry failed, entry:parentToken:747441 entryMask:ffffffffffffffff index:52. PR1575310

  • On the MX150 routers, interfaces might take a long time to power down while rebooting, powering-off, halting, or upgrading. PR1575328

  • The show services service-sets statistics syslog command returns the following error message as the service-set does not have the syslog configuration: error: usp_ipc_client_recv_ 1237: ipc_pipe_read fails! error:No error: 0(0), tries:1. PR1576044

  • Verification of NAT POOL DETAIL fails while verifying the SIP and bi-directional mapping with the block-size configured as default. PR1576398

  • On the MX10016 routers, when the Fan X Failed alarm is cleared in the Fan Tray 1, the Fan/Blower OK SNMP traps are generated for the Fan Tray 0 [Fan 31 - 41] and Fan Tray 1 [Fan 11 - 41]. PR1576521

  • With sharding configuration enabled, the RPD process generates core file at rsi_configipc_shardsprocess, rpd_shard_infra_recv_handler, (jp=< optimized out>) at ../../../../../../../../src/junos/usr.sbin/rpd/lib/jipc-infra/rpd_jipc_infr a_ipc.c:813.


  • On the MPC11E line cards, system resource monitor does not list some of the available Packet Forwarding Engines. PR1579975

  • On the MX480 routers, the SLIP messages are observed while testing the inline GRE reassembly feature with the GRE interface scaling. PR1581042

  • In the NAT64 scenario during session creation, IPv6 atomic fragments are not processed correctly. PR1581348

  • ISSU status displays errors with the reason of disconnection after ISSU and before switchover. PR1581380

  • When the MX Series device is in the SAEGW-U mode, in rare cases of a double back-to-back failover involving GRES and Node Association release, some access-peers might not be freed (even after the sessions count associated with that peer reaches zero). PR1549689

  • On the MX2010 and MX2020 devices, the following error message might be seen after switchover with GRES/NSR: CHASSISD_IPC_FLUSH_ERROR. PR1565223

  • Core files are generated at export_svc_set_nat_idl@nsd_calloc while verifying the no-translation with destination-nat. PR1568997

  • On the MX960 devices, the 400G and 4x100G optics laser restores after reboot despite interface disable being configured. PR1582418
  • The rpd might crash due to a rare timing issue if both BGP Local-RIB and Adjacency-RIB-In route monitoring are enabled in BMP. PR1584560

  • On the ACX5448 router, latency occurs for the host-generated ICMP traffic. PR1380145

  • Cattle-Prod daemon receives unknown trigger (type Semaphore, id 1) error messages on the vty when you commit the CLI commands to fetch host route scale. PR1554140

  • TCP session does not establish on the DCPFE restart on the primary node. PR1557607

  • The show pim join extensive source downstream-count command does not show the expected count of 100 on the aggregated Ethernet interface. PR1558349

  • The BFD sessions takes more time to come up in a scaled configuration in the AFT-based line cards on the configuration load. PR1582600

  • On the MX2020 routers with the 4x100G port using 4x100G optics, only the 1x400G and 4x100G modes are supported. PR1583200

  • After performing NSSU, the following error message occurs while checking the version detail:



  • The HSRPv2 IPv6 packets might get dropped if IGMP snooping is enabled. PR1232403

  • The following error message is observed continuously in AD with base configurations:

  • User while loading the kernel displays the following error message: GEOM: mmcsd0s.enh: corrupt or invalid GPT detected. PR1549754

  • SPC3 is not supported. PR1561188

  • Unable to find the 00:55:44:33:22:11 source MAC address in the packet capture on 10/18 connected to the CE device while testing EVPN. PR1562539

  • Moving the line card from SLC to full the line card mode results in FPC getting stuck as the SPMB does no reply in an extremely rare scenario.PR1563050

  • The adaptive load-balancing deviation is more than the expected count. PR1564133

  • Adding new template in the p2mp RSVP LSPs shows old template. PR1564795

  • The Synchronous Ethernet to PTP noise transfer test fails. PR1566291

  • The G.8273.2 Transient Response test fails. PR1566354

  • The Average Time Error(cTE) test fails when the PTP master and slave are on the different line cards. PR1567662

  • Request chassis SFB slot 6/7 offline shows the following message when all SFB are given and do not go offline on Bsys:


  • The MAC address does not expect the flag, source, and logical address in BD BD-3 instance. PR1569546

  • The RPIO_TUNNEL process generates the core file at rpio_die ioctl_send rpio_tunnel_set_ioctl. PR1569912

  • Hundred percent DCI traffic is lost in the transit spine devices. PR1572238

  • The TFEB or FPC process might fail to be online after the system or the FPC process reboots if interface-set is configured for CoS. PR1572348

  • After optics OIR, some of the channels display additional link flap. PR1577676

  • PCIe corrected and uncorrected alarms occurs on FPC during SLC bootup. PR1578187

  • Multicast traffic destined to from R0 to R4/R3 does not flow with the PS/AF configuration on R1. PR1578760

  • The MPC7E, MPC8E, MPC9E, and MPC11E line cards might be stuck in the Unresponsive state in a Junos Node Slicing setup. PR1580168

  • The Inline Jflow Routing Engine command is handled at a low priority than the routes and nexthops learning. When the Packet Forwarding Engine is busy downloading the routes and nexthops (for example, commit, route convergence, and link flap), the inline Jflow related statistics command might be timed out. This error message is harmless and indicate that the statistics command did not succeed. PR1580362

  • Complete FPC restarts on repeated SLC restarts. PR1581107

Interfaces and Chassis

  • On the MX480 routers, the output of the show interfaces transport pm otn current < interface> command is not as expected. PR1560533

  • On the MX2020 routers, the MM TXED is not the same as LMR RX due to packet loss with cycle time 100ms. PR1561397

Juniper Extension Toolkit (JET)

  • Abrupt shutdown or closure of the collector port results in GRPC connection with the same client ID to fail till all the devices are disconnected. PR1549044

Layer 2 Ethernet Services

  • The OSPF and OSPF3 adjacency uptime are more than expected after the NSSU, and outage is higher than expected. PR1551925

  • ZTP not activated after restarting the device once or twice. PR1529246


  • Extended-admin-groups on links are shown as the SRLG attribute in TED. PR1575060

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

  • The rpd process generates core file during GRES at mpls_tunnel_selfID_update ,p2mp_branch_update_selfID ,rsvp_nhop_lookup ,rsvp_change_label_for_appl_p2mp_session. PR1559022

  • The show mpls lsp statistics ingress name pe1-to-pe2 command displays the packet count in one LSP instead of displaying the packet count in two LSPs as expected. PR1565450

Network Address Translation (NAT)

  • Services NAT mappings and sessions are incorrect while checking the SIP sessions from public to private and RTP from private to public. PR1577922

Platform and Infrastructure

  • The MX Series router might drop packets larger than the tunnel interface MTU as tail drops in an egress queue. PR1386350

  • The vmxt_lnx process generates a core file at KtreeSpace::FourWayLeftAttachedNode::getNextDirty Trinity_Ktree::walkSubTree Trinity_Ktree::walkSubTree. PR1525594

  • Upgrading satellite devices might lead to some SDs in the SyncWait state. PR1556850

  • The BFD session goes down after ISSU switchover. PR1561306

  • The show ddos-protection protocols violations command does not show any violation with the scaled 4000 logical interface configuration. PR1577957

  • On the MX960 routers, ethernet-output-bytes are not in the expected range while verifying the Ethernet MAC level with both the IPv4 and IPv6 traffic for the VLAN tagged interfaces. PR1579797

Routing Policy and Firewall Filters

  • When upgrading Junos OS to a specific version, the configuration validation might fail and the rpd process might crash. PR1538172

  • COS queue egress interface forwarding-class might not work as expected. PR1538286


Routing Protocols

  • On the MX960 router, the backup path fails to install in the LAN scenario and breaks the SR-MPLS for LAN when more than four end-x SIDs are configured on the interface.

  • The routes are not copied from the transport ribs (junos-rti-tc-200.inet.3) to bgp.transport.3 in the device with transport. PR1556632

  • The BGP session flaps might be seen after the Routing Engine switchovers when the VRRP virtual address is used as the local address for the BGP session. PR1576959

  • Possible RPD crash with the routing-options transport-class configuration during the restart routing is observed. PR1582081

  • On the MX960 routers, the next-hop entries in table inet.0 are not as expected when testing the IS-IS policy LFA. PR1558581

  • IS-IS adjacency is not as expected when testing the BGP community feature using VRR. PR1559079

  • More ssh connections are allowed than the configured ssh connection limit. PR1559305

  • The DHCP BFD subscriber session does not come up on the MPC Type 2 card and gets stuck in the Down state. PR1572577

  • The dcpfe process might crash when an interface flaps. PR1579736

Subscriber Access Management

  • Subscriber might get stuck in the Terminating state if the Access-Challenge packet is received from the RADIUS server during the subscriber authentication. PR1583090

User Interface and Configuration

  • Commit fails for the backup Routing Engine for the deactivated mpls lsp priority command. PR1519367



  • Traffic from the reverse direction might cause traffic loss for up to 1 second with NSR switchover. PR1558395

  • During ISSU from Junos OS Release 18.4R1 to Junos OS Release 19.1, traffic through IPSEC VPN fails. PR1416334

  • Stop or start of pim join from RT results in traffic error for four traffic streams. PR1576954