Juniper MX接口栈介绍.pdf

接口栈 SUMMER 理解接口栈的概念，了解接口如何创建，接口之间如何嫁 接等等，这对理解MX作为BRAS如何部署业务，如何管理 接入用户起着至关重要的作用。本文从三个方面加以阐述： 接口的类别、属性 各种典型业务情况下接口栈如何嫁接 各种典型配置和验证。 备注：为简化，本文只是为了讲述接口栈，没有涉及到接口上复杂的特性，比 如接口上的filter, QOS等等。 IFX IFD - The Interface Device contains the physical interface config. IFL - The Logical Interfaces. It contains the L2 protocol config and is the interfaces for forwarding and routing IFF - The Interface Family is used to configure Layer3 protocol configuration. IFA - The Interface Address is used to configure Layer3 addresses on families. 3 Copyright © 2012 Juniper Networks, Inc. INTERFACE HIERARCHY (IFD) ifdev (aka IFD) –One for each piece of network hardware in the system (almost)  Not all IFD’s have an associated physical hardware (e.g. lo0, ae0, dsc, gre, ipip, .local.. Etc.) – Holds most procedure handles for the device driver and device specific information –Added as part of device discovery  Autoconfig time for RE devices  Chassisd added for PFE devices – Layer 1 data structure 4 Copyright © 2012 Juniper Networks, Inc. INTERFACE HIERARCHY (IFD) … How do we identify IFDs in the system? – By name (ge-x/y/z) x – FPC slot y – PIC slot z – Port on the PIC The kernel maintains a patricia tree based on the IFD name – By ifd index Assigned by the kernel when an IFD is created – By snmp Id 5 Copyright © 2012 Juniper Networks, Inc. INTERFACE HIERARCHY (IFD) … Procedure handles for device driver – ifd_devoutput Routine to send packet out of this interface – ifd_iflinput Routine to receive packets from this interface – ifd_ifdconfig Routine to configure this interface – ifd_ifdstat Stats collection routine – ifd_iflconfig ADD/DEL/CHG IFLs (e.g. ether_ifconfig) – ifd_pfe_iflconfig PFE specific work (e.g. stats memory allocation, etc.) – i