What do WRED drops and Policing drop on qos mean?

[KiCheon.Lee]

Hello

I have made qos configuration.

I have questions when am checking qos.

Look at the following command

show qos interface ethernet1/1 hw-counter

qid   name                 pass bytes       WRED drop   policing drop

--------------------------------------------------------------------------------

0     default              3408809811               0               0

-2    bypass              14803984933          584640               0

I don't know what WRED drop and policing drop mean and what two counters are difference.

[mbutt]

Hi,

Congestion Management

When a queue is filling faster than it can be emptied, the device has two choices as to where to drop traffic. It can wait until the queue is full and simply drop packets as they arrive (tail dropping), or it can detect incipient congestion and proactively begin to drop packets based on probability function that is tied to average depth of the queue. This technique is called random early drop (RED). PAN-OS uses weighted RED (WRED) algorithm.

Policing and Shaping

Policing is performed to avoid unintentional starvation of the QoS priority queues. Policers mark packets that go above the burst rate as out of conformance, which alerts the scheduler to allow the packets to be forwarded only if the interface is not experiencing congestion. When the interface is experiencing congestion, out of conformance packets are either automatically discarded or reclassified.

Not all Palo Alto Networks firewalls support policing, refer to the following table:

Platform Policing

PA-200

Not Supported

PA-500

Not Supported

PA-2000 Series

Not Supported

PA-4000 Series

Supported (on egress interface)

PA-5000 Series

Supported (on egress interface)

Also following doc has the same information on page 5.

QoS in PAN-OS

Hope this helps.

Thank you

Numan

[KiCheon.Lee]

Hi

Thanks for the answer.

If I don't make QoS configuration, FW will be performed tail dropping on congestion management.

And if I make QoS Configuration, FW will be performed WRED on congestion management.

Right??

[SilverTiger]

I don't know exact this function still

It is hard to understand

Will you plz let me know to show what it is?