C H A P T E R 1 4-Port Oc-3/Stm-1 Atm Line Card Configuration - Cisco 10000 Series Configuration Manual

Chapter 1 4-Port OC-3/STM-1 ATM Line Card Configuration
The number of SAR priority levels and the service categories supported at each priority level vary from
line card to line card. For example, the 4-port OC-3 line card supports the two levels of priority and the
service categories listed in
The ATM line cards support a maximum number of VCs per priority. That VC limit depends on the VC
limit of the SAR (SAR limit) and the number of priority levels configured.
determine the VC limit per priority level per port for the 4-port OC-3 line card.
Table 1-4
ATM Line Card
4-Port OC-3
Configuring more channels or VCs than there are available priority locations can cause random channels
or VCs to get stuck in the SAR. This occurs when an active channel tries to reschedule itself, but no
priority locations are available. Therefore, the channel cannot find a place to reschedule itself, which
results in a lost event for the channel, and the channel becomes stuck in the SAR.
On the PRE2, when a VC becomes stuck in the SAR, the PRE2 scheduler stops forwarding traffic on
only the VC that is stuck in the SAR; the other VCs still carry traffic. On the PRE3, the PRE3 scheduler
stops forwarding traffic on all the VCs configured on that ATM line card.
Interface Syntax
To specify an interface number in a configuration command, use the syntax in
interfaces and subinterfaces on the 4-Port OC-3/STM-1 ATM line card in Cisco Series 10000 routers.
Table 1-5
Type of Interface
Main interface
Subinterface
Main interface
Subinterface
Examples:
•
•
OL-8834-04
Table
Maximum Number of VCs per Priority
SAR Priority Levels
0 = CBR, VBR-nrt VCs
1 = UBR VCs
4-Port OC-3 ATM Interface Syntax
Router
10008
10008
10005
10005
Modify a PVC associated with the main interface.
Router(config)# interface atm 2/0/0
Router(config-if)# pvc 0/200
Router(config-if-atm-vc)#
Modify a permanent virtual circuit (PVC) associated with a subinterface.
Router(config)# interface atm 7/0/0.1
Router(config-subif)# pvc 0/101
Router(config-if-atm-vc)#
1-4.
VC Rate
Half line rate
and below
Slot Subslot
1 through 8/ 0/
1 through 8/ 0/
1 through 5/ 0/
1 through 5/ 0/
Cisco 10000 Series Router Line Card Configuaration Guide
Table 1-4
Maximum Number of VCs per Priority
SAR limit / number of PHYs / number of
priority levels
2 priority system:
65,536 / 4 / 2 = 8192 VCs per priority level
per port
Table 1-5
Port Subinterface
0 to 3 —
0.n to 3.n n = 1 to 4294967295
0 to 3 —
0.n to 3.n n = 1 to 4294967295
Interface Syntax
describes how to
to identify main
1-3