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Known Limitations


This section contains the known behaviors, system maximums, and limitations in hardware and software in Junos OS Release 15.1X49-D230.

Chassis Clustering

  • In a chassis cluster setup on SRX550M devices, traffic loss for about 10 seconds is observed when there is a power failure on the active chassis cluster node. PR1195025

  • IP monitoring for redundancy groups might not work on the secondary node if the reth interface has more than one physical interfaces configured. This is because the backup node sends traffic using the MAC address of the lowest port in the bundle. If the reply does not come back on the same physical port, then the internal switch drops the traffic. PR1344173

Flow-Based and Packet-Based Processing

  • On SRX340 and SRX345 devices, half-duplex mode is not supported. PR1149904

  • On SRX300 and SRX320 devices, link mode cannot be set to half-duplex mode on internal small form-factor pluggable (SFP) ports. PR1165259

  • On SRX Series devices, after the user changes some interface configurations, a reboot warning message might appear. The warning message is triggered only when the configuration of the interface mode is changed from route mode to switching mode or mixed mode. This is a configuration-related warning message, so it might not reflect the current running state of the interface mode. PR1165345

  • On SRX300, SRX320, SRX340, SRX345, and SRX550M devices, the current Ethernet switching MAC aging uses software to age out MAC addresses learned in bulk. You cannot age out a specific MAC address learned at a specific time immediately after the configured age. The MAC address might age out close to two times the configured age-out time. PR1179089

  • On SRX Series devices, the show arp command displays all the ARP entries learned from all interfaces. While switching to Layer 2 global mode, the ARP entries learned from the IRB interface show only one specific VLAN member port instead of the actual VLAN port learned in the ARP entries. PR1180949

  • On SRX300, SRX320, SRX340, and SRX345 devices, you cannot launch the setup wizard by using the reset configuration button when the device is in Layer 2 transparent mode. You can launch the setup wizard by using the reset configuration button on the device only when the device is in switching mode. PR1206189

  • On SRX300, SRX320, SRX340, SRX345, and SRX1500 devices, the vSRX 2.0 command set system internet-options tcp-mss does not work in Junos OS Release 15.1X49. PR1213775

  • On SRX300, SRX320, SRX340, SRX345, SRX550M, and SRX1500 devices, VPLS and Ethernet switching must not be configured together on the same device. We recommend that you avoid using an Ethernet-switching configuration on these platforms when VPLS is enabled. PR1214803

  • On SRX345 and SRX550M devices, frames carried with a priority bit on the Tag Protocol Identifier (TPID) are lost when the packet passes through with Layer 2 forwarding. PR1229021

  • On SRX300, SRX320, SRX340, SRX345, and SRX550M devices, after a certain period of enabling 802.1X, multiple first-message EAP frames with the same timestamp are transmitted. This does not affect any 802.1X functionality. PR1245325

  • A modem profile is not active until the profile is defined. You need to define a profile before selecting it. PR1254427

  • On SRX300, SRX320, SRX340, SRX345, and SRX550M devices, use the logical tunnel interface lt-0/0/0 as the destination interface option for an RPM probe server on the device. PR1257502

  • On SRX Series devices, you cannot create profiles for CL-1/0/0 using J-Web and the CLI. The error message interface not found is displayed. We recommend that you use only one LTE Mini-PIM in the supported devices. PR1262543

  • On SRX Series devices, when you log in to J-Web, and navigate to Monitor>Services>DHCP>DHCP Relay, and click the Help page icon, the Online Help page displays a 404 error message. PR1267751

  • A FIPS core file is generated when you perform a firmware upgrade or downgrade. In Junos OS FIPS mode, the file integrity checking application veriexec treats the new updated firmware file as a corrupted Junos OS file. PR1268240

  • On SRX Series devices, you cannot view the custom log files created for event logging in J-Web. PR1280857

  • On SRX300, SRX320, SRX340, SRX345, and SRX550M devices, using an SFP-T module can cause an early linkup if you connect a device during the boot process. PR1314167

  • On SRX Series devices running Junos OS Release 15.1X49-D90 and earlier releases, J-Web often does not display the IPD log that is locally saved. PR1336341

  • Packet reordering occurs on the traffic received on the PPP interface. PR1340417

  • FTP using Microsoft NLB does not work correctly in transparent mode. PR1341446

  • When using a crossover cable, the interfaces are down when there is a change from 10 million to 100 million. PR1387978

  • When using advanced, application-based, multipath routing, the sender sequences packets in order and delivers the packets to the receiver. If the receiver receives the packets out of order, then in Junos OS Release 15.1X49-D200 and later, the packets are dropped. Because IPsec might reorder packets coming from the sender for fragmentation, packets might get dropped at the receiver. PR1403584

  • SRX320 PoE devices do not support LLDP from Junos OS Release 15.1X49-D170 onward. PR1438467


  • On SRX550M and SRX1500 devices, there is no option to configure Layer 2 firewall filters from J-Web, irrespective of the device mode. PR1138333

  • On SRX Series devices, adding 2000 global addresses at a time to the addresses exempted in the SSL proxy profile can cause the webpage to become unresponsive. PR1278087

  • On SRX Series devices using Junos OS Release 15.1X49, a J-Web operation does not reset the idle time in the output of the show system users command. PR1445779

Platform and Infrastructure

  • When an NTP server is newly added to the Junos configuration using a domain name, a DNS server IP address needs to have been already configured and committed in a previous commit. Otherwise the commit will fail due to the NTP server domain name failing to be resolved to an IP address. As a workaround, use an IP address for the NTP server configuration. PR1411396

Unified Threat Management (UTM)

  • On SRX Series devices with Sophos Antivirus (SAV) configured, some files that have size larger than the max-content-size might not go into fallback state. This might occur when a protocol does not predeclare the content size. PR1005086

  • On SRX550M devices using Junos OS Release 12.1X49-D30 for the enhanced Web filtering feature, performance drop is observed. PR1138189