Cisco ASR1002 Configuration Guide - Page 240

Configuring the Cisco ASR 1000 Series Router for High Scalability Broadband Scalability and Performance VPDN Group Session Limiting Using the Virtual Private Dialup Network (VPDN) Group Session Limiting feature, you can limit the number of VPDN sessions allowed per VPDN group. VPDN session limits can increase performance and reduce latency for routers that are otherwise forced to operate at high capacity. For more information about VPDN Group Session Limiting, see the feature documentation at: http://www.cisco.com/en/US/docs/ios-xml/ios/vpdn/configuration/xe-3s/vpd-tunnel-mgmt.html PPPoE Session Limiting The PPPoE Session Limit Support feature prevents the router from using too much memory for virtual access by limiting the number of PPPoE sessions that can be created on a router or on all Ethernet interfaces and subinterfaces as well as ATM interfaces and subinterfaces. For more information about PPPoE session limiting, see the feature documentation at: http://www.cisco.com/en/US/docs/ios-xml/ios/bbdsl/configuration/xe-3s/bba-limit-legcfg-xe.html Monitoring PPP Sessions Using the SNMP Management Tools To prevent the virtual access subinterfaces from being registered with the Simple Network Management Protocol (SNMP) functionality of the router and using up the memory, do not use the SNMP management tools of the router to monitor PPP sessions. Use SNMP views to isolate the bulk queries and accidental requests. Use the no virtual-template snmp command to disable the SNMP management tools: Router(config)# no virtual-template snmp Configuring the Access Interface Input and Output Hold Queue The default value of Gigabit Ethernet and 10 Gigabit Ethernet interfaces is 375 packets for the input and output hold queues. If the interfaces are required to handle a high rate of control packets, such as LCP, IPCP, PPP, L2TP, and DHCP, the default value may not be sufficient. To ensure high scalability, set the access interface input and output hold queue to 4096: Router(config)# interface gig1/0/0 Router(config-if)# hold-queue 4096 in Configuring the keepalive Command For PPP sessions, the keepalive command sets the keepalive timer for a specific interface. To ensure proper scaling and to minimize CPU utilization, set the timer for 60 seconds or longer. The default value is 10 seconds: interface Virtual-Template1 ip unnumbered Loopback1 keepalive 60 no peer default ip address ppp authentication pap Cisco ASR 1000 Series Aggregation Services Routers Software Configuration Guide 6