4500 Line Card Oversubscription and Port Groups

[Muhammad Zeeshan Sanaullah]

Hi,

I have WS-X4448-GB-SFP Line Card Installed in 4507R Chasis (Classic Chasis not E Series). The chasis supports only 6 Gbps per line card. Which means the line card is 8:1 oversubscribed. As per the Data Sheet

WS-X4448-GB-SFP:

• 48  ports

•  1000BASE-X (SFP)

• Cisco  IOS Software Release 12.2(20)EW or later

• IEEE  802.3x flow control

•  Bandwidth is allocated across six 8-port groups, providing 1 Gbps per  port group

•  Enterprise and commercial: designed for server farms and  switch-to-switch applications

• Metro  Ethernet: designed for service providers to run point-to-point Gigabit  Ethernet over single-mode fiber

Now my question is how do you find the port groups. Which ports are part of which port group ... is it like Port Group 1 = Ports 1 to 8 and Port Group 2 = Port 9 to 16 and so on .... or any other way

Thanks

Zeeshan Sanaullah

[Giuseppe Larosa · Accepted solution]

Hello Zeeshan,

we have seen this in action on WS-4548 the port groups are made of :

1-8

9-16

17-24

and so on

I would expect the same on WS-4448

there is a specific document about oversubscription on C4500 linecards

each group shares one ASIC chip with 1 Gbps capability, there is no local switching that is traffic between ports count too.

Hope to help

Giuseppe