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buffer-size (Schedulers)


Hierarchy Level


Specify buffer size.


On PTX Series Packet Transport Routers, buffer-size cannot be configured on rate-limited queues.


If you do not include this statement, the default scheduler transmission rate and buffer size percentages for queues 0 through 7 are 95, 0, 0, 5, 0, 0, 0, and 0 percent, respectively.


percent percentage

Buffer size as a percentage of the total buffer.

  • Range: 0 through 100


    For the routers with channelized OC12/STM4 IQE PIC with SFP (PB-4CHOC12-STM4-IQE-SFP) and channelized OC48/STM16 IQE PIC with SFP (PB-1CHOC48-STM16-IQE-SFP), the minimum buffer allocated to any queue is 18,432 bytes. If a queue is configured to have a buffer size less than 18K, the queue retains a buffer size of 18,432 bytes.


Remaining buffer available.


On PTX Series routers, set a queue’s buffer to be up to 100 percent of the interface’s buffer. This option allows the queue’s buffer to grow as large as 100 percent of the interface's buffer if and only if it is the only active queue for the interface.

temporal microseconds

Buffer size as a temporal value. The queuing algorithm starts dropping packets when it queues more than a computed number of bytes. This maximum is computed by multiplying the logical interface speed by the configured temporal value.

  • Range: The ranges vary by platform as follows:

    • For SRX Series Firewalls: 1 through 2,000,000 microseconds.

    • For vSRX instances: 1 through 32,000,000 microseconds.

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Release Information

Statement introduced before Junos OS Release 7.4.

shared option introduced in Junos OS Release 18.1 for PTX Series Packet Transport Routers.