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Junos OS Release Notes for ACX Series

 

These release notes accompany Junos OS Release 19.1R3 for the ACX Series. They describe new and changed features, limitations, and known and resolved problems in the hardware and software.

You can also find these release notes on the Juniper Networks Junos OS Documentation webpage, located at https://www.juniper.net/documentation/product/en_US/junos-os.

What's New

Learn about new features introduced in the Junos OS main and maintenance releases for ACX Series routers.

What's New in Release 19.1R3

There are no new features or enhancements to existing features for ACX Series Universal Metro Routers in Junos OS Release 19.1R3.

What's New in Release 19.1R2

There are no new features or enhancements to existing features for ACX Series Universal Metro Routers in Junos OS Release 19.1R2.

What's New in Release 19.1R1

Authentication, Authorization, and Accounting (AAA) (RADIUS)

  • Support for SFTP global disablement (ACX Series)—Starting in Junos OS Release 19.1R1, we have globally disabled incoming SSH File Transfer Protocol (SFTP) connections by default. You can enable incoming SFTP connections globally by configuring the statement sftp-server at the [edit system services ssh] hierarchy level. Prior to Junos OS Release 19.1R1, the incoming SFTP connections were globally enabled by default.

    [See Configuring sftp-server.]

Platform and Infrastructure

  • DMA recovery mechanism (ACX Series)—A recovery mechanism has been introduced that is triggered in case the router enters an Idle state on any DMA channels. The recovery mechanism reboots the Packet Forwarding Engine to recover from Idle state.

    The following recovery message is logged in the Routing Engine syslog message:

    The following recovery message is logged in the Packet Forwarding Engine syslog message:

Routing Protocols

  • Support for BGP graceful shutdown (ACX Series)— Starting in Junos OS Release 19.1R1, graceful traffic migration from one BGP next hop to another is supported, without traffic interruption. Also, BGP administrative shutdown communication can be sent to the BGP peer.

    You can configure both graceful-shutdown and shutdown statements at the [edit protocols bgp], [edit protocols bgp group group-name], and [edit protocols bgp group group-name neighbor address] hierarchy levels.

    Note

    Graceful shutdown is disabled by default.

    [See graceful-shutdown (Protocols BGP), shutdown (Protocols BGP).]

What's Changed

Learn about what changed in the Junos OS main and maintenance releases for ACX Series routers.

What’s Changed in 19.1R3

General Routing

  • Advertising 32 secondary loopback addresses to traffic engineering database as prefixes (ACX Series, EX Series, MX Series, PTX Series, QFX Series, and SRX Series)—We've made changes to export multiple loopback addresses to the lsdist.0 and lsdist.1 routing tables as prefixes. This eliminates the issue of advertising secondary loopback addresses as router IDs instead of prefixes. In earlier releases, multiple secondary loopback addresses in the traffic engineering database were added to the lsdist.0 and lsdist.1 routing tables as part of node characteristics and advertised them as the router ID.

  • Support for unicast ARP request on table entry expiration—You can configure the device to send a unicast ARP request instead of the default broadcast request when an ARP table entry is about to expire. The retry requests are unicast at intervals of 5 seconds. Without this option, the retry requests are broadcast at intervals of 800 milliseconds. This behavior reduces ARP overall broadcast traffic. It also supports the use case where access nodes are configured not to forward broadcast ARP requests toward customer CPEs for security reasons and instead translate ARP broadcasts to unicast requests. To confirm whether this is configured, you can issue the following command: show configuration system arp | grep unicast-mode-on-expire.

    [See arp.]

What’s Changed in 19.1R2

Interfaces and Chassis

  • Support for disabling RS-FEC (ACX6360-OX)—By default, Junos OS software enables or disables forward error correction based on plugged-in optics. Starting with Junos OS Release 19.1R2, on ACX6360-OX routers used as Transponders, you can now disable Ethernet FEC, also known as RS-FEC or FEC91. Previously, RS-FEC was enabled by default and could not be disabled.

    [See fec.]

Network Management and Monitoring

  • The show system schema command and <get-yang-schema> RPC require specifying an output directory (ACX Series)—Starting in Junos OS Release 19.1R2, when you issue the show system schema operational mode command in the CLI or execute the <get-yang-schema> RPC in a remote session to retrieve schema files, you must specify the directory in which to generate the output files by including the output-directory command option in the CLI or the <output-directory> element in the RPC. In earlier releases, you can omit the output-directory argument when requesting a single module to display the module in standard output.

What’s Changed in 19.1R1

Interfaces and Chassis

  • Support for creating Layer 2 logical interface independently (ACX Series, EX Series, MX Series, PTX Series, and QFX Series)—In Junos OS Releases 18.4R1, 18.4R2, 19.1R1, and later releases, ACX Series routers support creating Layer 2 logical interfaces independent of the Layer 2 routing-instance type. That is, you can configure and commit the Layer 2 logical interfaces separately and add the interfaces to the bridge domain or Ethernet VPN (EVPN) routing instance separately. Note that the Layer 2 logical interfaces work fine only when they are added to the bridge domain or EVPN routing instance.

    In earlier Junos OS releases, when you use a Layer 2 logical interface configuration (units with encapsulation vlan-bridge configuration), then you must add the logical interface as part of a bridge domain or EVPN routing instance for the commit to succeed.

Network Management and Monitoring

  • NETCONF <kill-session> operation returns different values in <rpc-error> when the session identifier is equal to the current session ID (ACX Series)—Starting in Junos OS Release 19.1R1, when you execute the <kill-session> NETCONF operation and the session identifier is equal to the current session ID, the values of the <error-type> and <error-tag> elements in the resulting <rpc-error> are application and invalid-value, respectively. In earlier releases, the <error-type> and <error-tag> values are protocol and operation-failed.

    [See <kill-session>.]

  • sysName.0 MIB object displays the fully qualified domain name (ACX Series)—Starting in Junos OS Release 19.1R1, the sysName.0 MIB object displays the fully qualified domain name. That is, if the hostname and domain name are configured on the system, both will show up for the sysName.0 MIB object: host-name.domain-name. Previously, only the hostname showed up.

    [ee show snmp mib.]

Operation, Administration, and Maintenance (OAM)

  • Performance monitoring history data is lost when change in number of supported history records is detected (ACX Series and MX Series)—In Junos OS Release 19.1R1, when Ethernet connectivity fault management starts, it detects the number of history records supported by the existing performance monitoring history database and if there is any change from the number of history records supported (that is, 12) in Release 19.1R1, then the existing performance monitoring history database is cleared and all performance monitoring sessions are restarted with mi-index 1.

Routing Policy and Firewall Filters

  • Firewall filters with IPv6 match conditions not supported on ACX6360-OR routers—Starting in Junos OS Release 19.1R1, firewall filters with Internet Protocol version 6 (IPv6) match conditions are not supported at the [firewall family inet6 filter name] hierarchy level on ACX6360-OR routers. Note that different Junos OS releases might have different support limits, for example 19.2R1.

Known Limitations

Learn about known limitations in this release 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

  • For an ACX5448, the theoretical limit of the ARP learning rate is approximately 150 ARP resolutions per second per logical interface. PR1343221

  • All PTP packets go to the best-effort queue instead of the network control queue. PR1361315

  • Junos telemetry interface infrastructure does not support interface filtering capability. After you enable a particular sensor for telemetry, it is turned on for all the interfaces. PR1371996

  • For an et- interface, only the PRE_FEC_SD defect is raised and no OTN alarm is raised. PR1371997

  • On an ACX6360 router, the static-cak command encryption does not work between two ACX-OX transponder nodes. PR1389802

  • For ACX6360 TIC, you have only 8 CFP2-DCO ports. The show chassis beacon or request chassis beacon command for port numbers larger than 7 does not work because the ports do not exist. However, no error is reported. user@router> request chassis beacon fpc 0 pic-slot 1 port 15 on FPC 0 PIC 1 PORT 15 ON regress@node> show chassis beacon fpc 0 pic-slot 1 port-range lower-limit 0 upper-limit 15 FPC 0 PIC 1 PORT 0 ON FPC 0 PIC 1 PORT 1 ON FPC 0 PIC 1 PORT 2 ON FPC 0 PIC 1 PORT 3 ON FPC 0 PIC 1 PORT 4 ON FPC 0 PIC 1 PORT 5 ON FPC 0 PIC 1 PORT 6 ON FPC 0 PIC 1 PORT 7 ON FPC 0 PIC 1 PORT 8 ON FPC 0 PIC 1 PORT 9 ON FPC 0 PIC 1 PORT 10 OFF FPC 0 PIC 1 PORT 11 OFF FPC 0 PIC 1 PORT 12 OFF FPC 0 PIC 1 PORT 13 OFF FPC 0 PIC 1 PORT 14 OFF FPC 0 PIC 1 PORT 15 ON PR1399335

  • ACX Series routers support only 900 joins of IGMPv3 users per second. PR1448146

Open Issues

Learn about open issues in this release 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

  • In the earlier scenario where only the PCS is down and PMD is up, the status is not sent to the MAC and no interruption is caused. However, the status is picked up as part of the 1- second periodic, where the link goes down for a second. In spite of taking the link status from the MAC, you can read the PHY status to avoid the intermittent link down status observed in the PCS as it is a sticky read. PR1223457

  • Upon classifying the Layer 3 packets, DSCP is not preserved and is lost at the egress due to the limitations of a chipset. PR1322142

  • On ACX5448 devices, when a 1-Gigabit SFP transceiver is installed, autonegotiation is enabled by default. There is no functional impact. Only the show interface extensive command shows the Auto-negotiation field as disabled. PR1343679

  • If the set interfaces ae<>xaggregated-ether-options link-speed command is configured in the router, the aggregated Ethernet interface remains down after rebooting. The following error message is observed: ================== /kernel: kernel did not add link ae1, link speeds differ 1000000000 10000000000 /kernel: bundle ae1.0: link xe-0/3/0 not added due to speed mismatch. PR1357012

  • ERP might not come up properly when MSTP and ERP are enabled on the same interface. PR1473610

  • The queue statistics are not as expected after configuring the IFD and logical interface shaping with the transmit rate and scheduler-map. PR1488935

  • Loopback status is not shown for OT interfaces on the CLI (available from vty only). PR1358017

  • The SD threshold is normally lower than the SF threshold, so that as errors increase, the SD condition is encountered first. For the ACX6360 optical links, there is no guard code to prevent you from setting the SD threshold above the SF threshold, which would cause increasing errors to trigger the SF alarm before the SD alarm. This does not cause any issues on systems with correctly provisioned SD or SF thresholds. PR1376869

  • On the ACX6360-OR router, enhancement is needed for FRR BER threshold SNMP support. PR1383303

  • On the ACX6360 and PTX10001 routers, Tx power cannot be configured using the + sign. PR1383980

  • The switchover time observed is more than 50 ms under certain soak test conditions with an increased scale and a multiprotocol multirouter topology. PR1387858

  • The circuit cross-connect logs are not compressed after rotation. PR1398511

  • A jnxIfOtnOperState trap notification is sent for all ot- interface. PR1406758

  • Packets transmitted in a queue are not as expected when testing the ieee-802.1ad inner classifier at the ingress and ieee-802.1ad rewrite at the egress with various events. PR1422515

  • Protocols get forwarded when you use the nonexisting SSM map source address in IGMPv3 instead of pruning. PR1435648

  • Memory leaks are expected in this release. PR1438358

  • dcpfe generates core files when you enable or disable MACsec through the Toby scripts. PR1479710

  • On the ACX5448 platform, multiple hardware I2C failures might be observed because of the intermittent I2C access failures on the main board internal switches. A system reboot is required to clear this state. PR1429047

  • The FPC might crash with the em2 interface configuration during initialization. PR1429212

  • On the ACX5048 Series router, the egress queue statistics are not working for the aggregated Ethernet interfaces. PR1472467

  • On the ACX5448 Serires router, the Layer 2 VPN with the ethernet-ccc input-vlan-map or output-vlan-map interface might cause traffic to be silently discarded. PR1485444

  • Need to disable the inet6-precedence statement under the [edit class-of-service rewrite-rules] hierarchy. PR1344340

  • Memory utilization enhancement is needed. PR1481151

  • On the ACX5000 router, the IEEE 802.1p priority and DEI values in the locally generated VLAN-based IP packets might be changed when sourced from the IRB interface. PR1490966

MPLS

  • When two directly connected BGP peers are established over MPLS LSP, if the MTU of the IP layer is smaller than the MTU of the MPLS layer and the BGP packets from the host have the DF bit set, the BGP session might keep flapping because of the use of wrong TCP-MSS. PR1493431

Resolved Issues

Learn which issues were resolved in the Junos OS main and maintenance releases 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.

Resolved Issues: 19.1R3

General Routing

  • On the ACX5000 line of routers, the following error message is observed: MacDrainTimeOut and bcm_port_update failed: Internal error PR1284590

  • The bcmDPC task is high even though the START_BY_START interrupt flag is set to 0. PR1329656

  • On the ACX5448 10-Gigabit, 40-Gigabit, and 100-Gigabit Ethernet interfaces, link fault signaling does not work. PR1401718

  • High CPU for fxpc processes with CoS, changes on aggregated Ethernet interfaces. PR1407098

  • Optics comes with Tx enabled by default. As the port is administratively disabled, the port is stopped. However, as the port has not been started, it does not disable Tx. PR1411015

  • The l2cpd process might crash and generate a core file when the interfaces flaps. PR1431355

  • On the ACX Series router, packet drop might be seen when chain composite is enabled for Layer 3 VPN. PR1439317

  • Interface on ACX1100 remains down when you use SFP-1FE-FX (740-021487). PR1439384

  • On the ACX5448 router, the encap flexible VLAN tagging is not supported with MPLS family. PR1445046

  • On the ACX5448-M router, fans might not run at the correct speed. PR1448884

  • FPC might generate core files after changing the configuration of PTP or Synchronous Ethernet. PR1451950

  • On the ACX5448 device, the Layer 2 VPN with the Ethernet encapsulation type stops passing traffic after a random port is added with VLAN configuration. PR1456624

  • The traffic might be discarded silently during link recovery in an open Ethernet access ring with ERPS configured. PR1459446

  • On the ACX5000 line of routers, the SNMP MIB walk for jnxOperatingTemp does not return anything for FPCs in all the new Junos OS Releases. PR1460391

  • On the ACX Series platforms, the LLDP neighbor does not come up on LAG interfaces after the software upgrade to Junos OS Release 18.2R3-S1. PR1461831

  • Not able to add more than 16 links in a lag. PR1463253

  • RED drops on interface even without any congestion. PR1470619

  • On the ACX5048 routers, the snmp polling gets stalled after the link flaps or the sfp gets replaced and the following error message is observed: ACX_COS_HALP(acx_cos_gport_sched_set_strict_priority:987): Failed to detach. PR1455722

  • Memory leakage on the l2cpd process might lead to l2cpd crash. PR1469635

  • The ACX5048 routfails to display the RFC2544 test statistics for the reflected packets. PR1451759

  • FPC might continuously crash after deactivating or activating the loopback filter or rebooting the system after configuring the loopback filter. PR1477740

Interfaces and Chassis

  • The status of the MC-AE interface might appear as unknown when you add the subinterface as a part of the VLAN on the peer MC-AE node. PR1479012

Routing Protocols

  • The rpd might crash continuously due to memory corruption in the IS-IS setup. PR1455432

Resolved Issues: 19.1R2

General Routing

  • The logical interfaces might not come up if scaled logical interfaces exist. PR1229492

  • The 1G copper module interface shows "Link-mode: Half-duplex". PR1286709

  • The fxpc process might use high CPU on ACX5000 after upgrade. PR1360452

  • FPC showing high CPU due to PIC PERIODIC. PR1360844

  • On an ACX Series ring topology, after the link between the ACX Series and MX Series devices flaps, the VPLS RI on the PE device (MX Series) has no MAC address for the CE device over l2circuit. over Layer 2 circuit. PR1360967

  • On an ACX Series devices, the LED on GE interface goes down when speed 10M is added. PR1385855

  • Traffic over the aggregated Ethernet physical interface might get filtered with the filter on one child logical interface on ACX Series. PR1407855

  • The show services inline stateful-firewall flow or show services inline stateful-firewall flow extensive command might cause the memory leak. PR1408982

  • ACX Series router drops DNS responses that contain an underscore. PR1410062

  • VPLS traffic might stop across ACX5000 with the aggregated Ethernet interface. PR1412042

  • Junos OS PCC might reject PCUpdate/PCCreate message if there is metric type other than type 2. PR1412659

  • The 40-GIgabit Ethernet FEC ACX5448 is ON by default. Need to align with MX Series and QFX Series platforms where FEC is NONE. PR1414649

  • Commit error while configuring firewall with term having log/syslog and accept actions. PR1417377

  • On the ACX448 devices, BFD timer value does not match the configured 900 ms with multiplier 3. It’s showing 6000 with multiplier 3 instead for most of the sessions. PR1418680

  • COS table error can sometimes cause traffic outages and SNMP timeouts if the optic is plugged out and inserted back. PR1418696

  • High CPU usage on fxpc process might be seen on ACX5000 platform. PR1419761

  • Slow copy image speed to ACX5448. PR1422544

  • Traffic might forward to wrong bridge-domain if you change interface encapsulation from Ethernet-bridge to VLAN-bridge. PR1423610

  • The JUNIPER_SOURCE LR4T2 optics might not work properly on ACX5448 platforms. PR1424814

  • The FPC/fxpc crash might be observed. PR1427362

  • Chassisd can crash with unsupported hcos configuration when MX104 is used as fusion aggregation device. PR1430076

  • On ACX5448 devices, upon reboot of MC_LAG peer, when peer comes up (but before hardware comes up) there is a 10-20 second traffic hit on node1. PR1430910

  • Auto-RP mapping might periodically time-out on ACX5448 platforms. PR1432889

  • ACX5448 might malfunction in encapsulating small packets if egress link is 40-Gigabit Ethernet or 100-Gigabit Ethernet. PR1434900

  • On ACXp Series latforms, no-vrf-propagate-ttl might not work after you activate or deactivate COS configuration. PR1435791

  • On ACX5448 routers, DHCP packets are not transparent over Layer 2 CIRCUIT. PR1439518

  • ACX5448: Packet buffer error from Packet Forwarding Engine leads to memory leak when IGMP is sent from NNI AC in Layer 2 circuit and VPLS. PR1442901

  • RED drops might be seen after link flaps or CoS configuration changes. PR1443466

  • On ACX Series routers, auto-exported route between VRFs might not reply for ICMP echo requests. PR1446043

  • On the ACX5448 Series router, Layer 2 circuit stops forwarding traffic after LDP flap. PR1448899

  • On the ACX5048 Series router, Layer 2 circuit with backup-neighbor configuration stops passing traffic after link flap and moves from backup neighbor to primary. PR1449681

  • On the ACX5448 Series router, the FPC crashes due to segmentation fault. PR1453766

  • FDB not flushing, silently discards the traffic in the Ethernet ring scenario. PR1459446

Class of Service

  • The dfwd crash can be seen with forwarding-class configuration in policers. PR1436894

Interfaces and Chassis

  • Family inet of the unnumbered interface might be getting deleted when deleting one of the IPs of the binding interface. PR1412534

  • Upgrade from Junos OS Release 17.4R1 and previous releases results in cfmd core file. PR1425804

Layer 2 Ethernet Services

  • DHCP request might get dropped in DHCP relay scenario. PR1435039

MPLS

  • MPLS ingress LSPs for LDP link protection are not coming up after disable/enable of MPLS. PR1432138

Platform and Infrastructure

  • REST API process will get non responsive when a number of requests start coming at a high rate. PR1449987

Routing Protocols

  • Loopback address exported into other VRF instance might not work on ACX Series platforms. PR1449410

  • MPLS LDP might still use stale MAC of the neighbor event though the LDP neighbor's MAC changes. PR1451217

Resolved Issues: 19.1R1

General Routing

  • SNMP MIB walk/get/set on jnxDomCurrentTable and jnxDomNotifications might fail on ACX Series platforms. PR1076943

  • ACX Series routers support dual-tagged through untagged packets Layer 3 traffic. PR1307666

  • ACX5000: fpc0 acx_rt_ip_uc_lpm_install:LPM route add failed error. Reason: Invalid parameter after configuring lpm-profile. PR1365034

  • VPLS with vlan-id-list is not working properly in some releases when the link between a PE device and a CE device is an aggregated Ethernet interface with a single member link and child physical interface flap. PR1365894

  • LIBCOS_COS_TVP_FC_INFO_NOT_FOUND: Forwarding-class information not specified prints while commit on configuration prompt. PR1376665

  • On ACX5448, channelized ET interface of 25-Gigabit Ethernet interface will not come up after chassis-control restart. PR1379288

  • The L2circuit might stop forwarding traffic when core interface flapping happens. PR1381487

  • Timestamp is incorrect for BER statistics after clearing. PR1386253

  • The request chassis beacon CLI command is not working for PIC slot 1 (that is, CFP2 ports). PR1386711

  • ACX 5448:100-Gigabit link FEC is enabled by default on 100-Gigabit LR4. PR1389518

  • On ACX Series platforms, the forwarding-option dhcp-relay forward-only command stops working and the DHCP packets are dropped. PR1392261

  • Certain builds of Junos OS do not allow you to upgrade or commit configuration changes when the SI service interface is used. PR1393729

  • MTU is not properly applied, and the output ping mpls l2circuit sweep is giving lower values than expected. PR1393947

  • This model of egress VPLS filter and the output of with physical-interface-specific semantic is only to be used to cater to use cases where there is a need to install a "physical-port-based" filter in the egress firewall. PR1395362

  • ACX5048 RPM RFC 2544 benchmarking test is failing to start. PR1395730

  • Error message ACX_PFE_ERROR: dnx_cfm_bd_endpoint_create: Failed to destroy the remote endpoint, Endpoint id 0x2001001, Entry not found been logged. PR1397878

  • Error message ACX_ASIC_PROGRAMMING_ERROR: dnx_cfm_bd_endpoint_create: Failed to create the local endpoint Invalid parameter been logged on peer node. PR1397951

  • Output packet error Count is 40-Gigabit Ethernet and 100-Gigabit Ethernet ports. PR1398270

  • High jsd or na-grpcd CPU usage might be seen even if JET or JTI is not used. PR1398398

  • Dynamic tunnels are not supported on ACX Series routers. PR1398729

  • ACX5448: Not able to configure bridge domain more than 1024, using 100-Gigabit and aggregated Ethernet interface in BD. PR1399214

  • FPC might crash after offline/online MIC-3D-16CHE1-T1-CE-H. PR1402563

  • ACX5448 supports TrTCM policer configuration parameters of RFC 4115. PR1405798

  • Aggregated Ethernet interface TWAMP history statistics verification on client is not getting expected "Request Timed Out" error. PR1411344

  • Number of inet-arp policers implemented on ACX5000 has been increased from 16 to 64. PR1413807

  • Swap memory is not initialized on boot on ACX5048. PR1415898

Infrastructure

  • The error of jlaunchd: disk-monitoring is thrashing, not restarted might be seen. PR1380032

Services Applications

  • The spd might crash when any-ip is configured in the from clause of the NAT rule with the static translation type. PR1391928

Documentation Updates

There are no errata or changes in Junos OS Release 19.1R3 documentation for the ACX Series.

Migration, Upgrade, and Downgrade Instructions

This section contains the upgrade and downgrade support policy for Junos OS for the ACX Series Router. Upgrading or downgrading Junos OS might take several minutes, depending on the size and configuration of the network.

For information about software installation and upgrade, see the Installation and Upgrade Guide.

Upgrade and Downgrade Support Policy for Junos OS Releases

Support for upgrades and downgrades that span more than three Junos OS releases at a time is not provided, except for releases that are designated as Extended End-of-Life (EEOL) releases. EEOL releases provide direct upgrade and downgrade paths—you can upgrade directly from one EEOL release to the next EEOL release even though EEOL releases generally occur in increments beyond three releases.

You can upgrade or downgrade to the EEOL release that occurs directly before or after the currently installed EEOL release, or to two EEOL releases before or after. For example, Junos OS Releases 17.1, 17.2, and 17.3 are EEOL releases. You can upgrade from Junos OS Release 17.1 to Release 17.2 or from Junos OS Release 17.1 to Release 17.3.

You cannot upgrade directly from a non-EEOL release to a release that is more than three releases ahead or behind. To upgrade or downgrade from a non-EEOL release to a release more than three releases before or after, first upgrade to the next EEOL release and then upgrade or downgrade from that EEOL release to your target release.

For more information about EEOL releases and to review a list of EEOL releases, see https://www.juniper.net/support/eol/junos.html.

For information about software installation and upgrade, see the Installation and Upgrade Guide.