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Open Issues

Learn about open issues in Junos OS Release 21.4R3 for ACX 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

  • VXLAN VNI (multicast learning) scaling on QFX5110 traffic issue is seen from VXLAN tunnel to Layer 2 interface. PR1462548

  • For ACX710, if the console cable is plugged in and the terminal connection is active and sending characters to the interface, the system boot may be interrupted and the ACX710 boot will be stalled at the uboot# prompt. PR1513553

  • Due to BRCM KBP issue route lookup may fail. PR1533513

  • On ACX5448 platforms, if hierarchical-scheduler is configured for an interface, during interface flaps or configuration changes, some of PFE buffers might become out of sync, which might cause packets drops even without congestion. PR1603622

  • On ACX platforms, traffic issue might be observed with downstream devices when Precision Time Protocol(PTP) is configured (G.8275.1 PTP profile) along with PHY timestamping and Multiprotocol Label Switching (MPLS) terminated on 10G interface. The transit PTP ipv4 packets are updated with wrong Correction Factor(CF). This issue could be restored by disabling PHY stamping. However, disabling might impact the PTP performance. PR1612429

  • There might be a DPDK (data plane development kit) Tx stuck issue and trigger a major chassis alarm goes which might trigger RG1 failover to the healthy node. A DPDK reset will be triggered only to the stuck port and if the reset resolves the tx stuck issue, the major chassis alarm will go off.PR1626562

  • For ACX5448, MX204 and MX2008 "VM Host-based" platforms, starting with Junos 21.4R1 or later, ssh and root login is required for copying line card image (chspmb.elf for MX2008) from Junos VM to Linux host during installation. The ssh and root login are required during installation. Use "deny-password" instead of "deny" as default root-login option under ssh config to allow internal trusted communication. Ref PR1629943

  • On ACX5448 and ACX710 platforms, all types of delegated BFD sessions configured on routing-instance other than the default routing-instance might not come up.PR1633395

  • For MX204, MX10003, ACX5448 platform, if a non-default ssh port is configured for system login, after upgrade to 21.4 release, the FPC is stuck in offline. To avoid such issue please use default SSH port and use protect RE filter to only allow the access from the trusted source.PR1660446

  • In VPLS MH cases, the standby UNI ifl in backup router will be programmed in disable state, by adding the UNI interface to invalid vpn id in HW. During switch over the UNI ifl will be deleted and will be added under the VPLS instance VPN id. In issue case, UNI interface added under invalid VPN id in backup router is tried to deleted by passing the VPLS instance vpn id, causing the issue. This issue is applicable only for ACX5k series.PR1665178


  • On all Junos platforms with MVPN scenario, stale PIM (S, G) state might be seen when there are no local/remote receivers and the multicast source is inactive. Only stale PIM entry will be seen, and it doesn't impact MVPN service or functionalities. PR1536903