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Changes in Default Behavior and Syntax in Junos OS Release 12.3 for EX Series Switches

This section lists the changes in default behavior and syntax in Junos OS Release 12.3 for EX Series switches.

Authentication and Access Control

  • Starting with Junos OS Release 12.3R10 for EX Series switches, the accounting-port CLI statement is supported at the [edit access radius-server server-address] hierarchy level on all EX Series switches. This command was previously supported only on EX4300, EX4600, and EX9200 switches. The accounting-port statement enables you to specify the port on which to contact the RADIUS accounting server. The default port number is 1813, as specified in RFC 2866.

Dynamic Host Configuration Protocol

  • When the DHCP relay agent receives a DHCP DISCOVER packet from a client while the client already has a binding on the relay that is in BOUND state, an OFFER message in reply might be dropped when sent from a server other than one to which the client is bound. You can now prevent this by using the new configuration statement delete-binding-on-renegotiation at the [edit forwarding-options dhcp-relay overrides] hierarchy level. When this option is configured, the client binding is removed on receiving a new DHCP DISCOVER packet from a client which is already in BOUND state and all OFFER messages in reply are relayed back to the client. [PR/1031605]

Layer 2 Features

  • On EX Series switches except for EX9200 switches, the vlan-tagging and family ethernet-switching statements cannot be configured on the same interface. Interfaces on EX2200, EX3200, EX3300, EX4200, and EX4500 switches are set to family ethernet-switching by the default factory configuration. EX6200 and EX8200 switch interfaces do not have a default family setting.


  • On EX Series switches, EX-SFP-1GE-LX40K SFP transceivers (length 40 km / 24.8 miles) are incorrectly recognized as LH transceivers—that is, in the show chassis hardware command output, the Description field lists them as SFP-LH. Starting with Junos OS Release 12.3R8, the Description field displays SFP-EX for these transceivers. [PR/977327]

High Availability

  • Change in the automatically generated virtual-link-local-address for VRRP over IPv6—The seventh byte in the automatically generated virtual-link-local-address for VRRP over IPv6 will be 0x02. This change makes the VRRP over IPv6 feature in Junos OS Releases 12.2R5, 12.3R3, and later releases inoperable with Junos OS Releases 12.2R1, 12.2R2, 12.2R3, 12.2R4, 12.3R1, and 12.3R2 if automatically generated virtual-link-local-address IDs are used. As a workaround, use a manually configured virtual-link-local-address instead of an automatically generated virtual-link-local-address.


  • You can now configure the disk usage monitoring level for a disk partition by using the set chassis disk-partition partition level state free-space threshold-value (mb | percent) configuration mode command. When the specified disk usage monitoring level is reached, a system alarm is activated. The partition can be /config or /var; the level of disk usage at which monitoring occurs can be high or full; and the threshold value can be either megabytes (mb) of disk space or a percentage (percent) of disk space. Here is a sample command: set chassis disk-partition /var level high free-space 30 mb.
  • These EX Series switches now support a maximum of 111 link aggregation groups (LAGs): EX3300, EX4200, EX4500, EX4550, and EX6210 switches.
  • On EX Series switches, the request chassis routing-engine master switch command erroneously showed the check option; the option does not apply and has been removed from the CLI.


  • LLDP frames are validated only if the Network Address Family subtype of the Chassis ID TLV has a value of 1 (IPv4) or 2 (IPv6). For any other value, LLDP detects the transmitting device as a neighbor and displays it in the output of the show lldp neighbors command. Earlier, the frames with the Network Address Family subtype of the Chassis ID TLV having a value of 1 (IPv4) or 2 (IPv6) were discarded, and LLDP did not detect the device as a neighbor.

Network Management and Monitoring

  • On EX Series switches that run Junos OS with Enhanced Layer 2 Software (ELS), you can now configure the adaptive sampling rate in sFlow monitoring technology configurations. You configure the rate with this command: set protocols sflow adaptive-sampling-rate rate. The maximum value for the rate is 950 pps.
  • New system log message indicating the difference in the Packet Forwarding Engine counter value (EX Series)—Effective in Junos OS Release 12.3R9, 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.

Related Documentation

Modified: 2017-03-07