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Changes in Behavior and Syntax


This section lists the changes in behavior of Junos OS features and changes in the syntax of Junos OS statements and commands from Junos OS Release 14.1R9 for the EX Series.

Dynamic Host Configuration Protocol

  • DHCP clients can send packets without Option 255 (EX9200)—On EX Series switches, starting with Junos OS Release 14.1R4, you can override the default configuration of the DHCP local server and enable clients to send DHCP packets that do not include Option 255 (end-of-options). The default behavior in Junos OS is to drop packets that do not include Option 255. To override that default behavior, configure the allow-no-end-options CLI statement at the [system services dhcp-local-server overrides] hierarchy level.


  • Change to CLI options for interface speed—On EX9200 switches, the CLI command set interfaces interface-name speed auto-10m-100m is not supported.

Network Management and Monitoring

  • New system log message indicating the difference in the Packet Forwarding Engine counter value (EX9200)—Effective in Junos OS Release 14.1R3, if the counter value of a Packet Forwarding Engine is reported lesser than its previous value, then the residual counter value is added to the newly reported value only for that specific counter. In that case, the CLI shows the MIB2D_COUNTER_DECREASING system log message for that specific counter.

Platform and Infrastructure

  • Changes in show chassis hardware command output descriptions for EX9200 components—Starting with Junos OS Release 14.1, the output of the show chassis hardware command includes descriptions for enhanced midplanes on EX9204 and EX9208 switches (enhanced midplanes are already on EX9214 switches and their descriptions included in the show chassis hardware command output) and the high-speed SF module EX9200-SF2, as highlighted in the following sample:

    user@switch> show chassis hardware