Clock settings

Unanswered Question
Nov 5th, 2007

Hi


I have a serial link between 2 routers running HDLC. The DTE router shows me

Available Bandwidth 1 kilobits/sec


And the DCE router shows me

Available Bandwidth 192 kilobits/sec


Am I correct by saying the clock rate must be set on the router? If this is the case, which router must be configured the DTE or DCE router?


Thanks

willemvw

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Kevin Dorrell Mon, 11/05/2007 - 04:39

The clock rate must be set on the DCE router. That is, assuming you are using a DTE-DCE back-to-back cable. You can confirm the cable by doing a show controllers for the interface at each end of the link.


However, the parameter you are observing is related to the configured "bandwidth", which is not directly related to the clock rate. In fact, the "Available bandwidth" is usually 3/4 of the configured bandwidth for the interface.


Which makes me wonder how you have 1 kbps on the DTE side. Can you post a show run int for each side?


Kevin Dorrell

Luxembourg


willemvwyk Tue, 11/06/2007 - 04:29

Hi Kevin


Below is the output for the interfaces of the 2 routers:


RT_01#sh run int s0/2/0

Building configuration...


Current configuration : 241 bytes

!

interface Serial0/2/0

description 256K Connect to RT_02

bandwidth 256

ip address 172.16.16.1 255.255.248.0

no ip route-cache cef

no ip route-cache

no ip mroute-cache

load-interval 30

compress stac

end


RT_01#


RT_02#sh run int s0/2/0

Building configuration...


Current configuration : 266 bytes

!

interface Serial0/2/0

description 256K Connect to RT_01

bandwidth 256

ip address 172.16.16.2 255.255.248.0

ip mtu 256

no ip route-cache cef

no ip route-cache

no ip mroute-cache

compress stac

service-policy output WAN-QoS

end


RT_02#


Thanks

willemvw

lgijssel Tue, 11/06/2007 - 04:39

The service policy on RT_02 has probably claimed a part of the bandwidth, which is why the available bandwidth displays a lower value.


As Kevin stated, the router keeps a certain amount of bandwidth (approx 75%) for system use (routing protocols etc)

You can modify this default with the following command:

max-reserved-bandwidth


regards,

Leo

Actions

This Discussion