Ixia updates NexGen framework in IxNetwork, that is great function and help tester simplified workload, but looks like the function couldn’t completely automate,  e.g when you config local address, GW address couldn’t auto-generate, you must manually change that, that should ok, everybody should fix that~ 🙂  But some issue will waste your time to troubleshooting. Summary two issues for the article that will help you fast to fix similar issues.

My IxNetwork version is 7.40.929.28.GA, GA version, wish to fix those issues at MR version 🙂

MALFORM update error on NCS5500

Introduction

Now more customer complains their Peering network not flexible and hard to control, that will cause peering link’s utilization not balance and waste of resources. As follow the example on Router-2, customer peering device connect to multi ISP, each ISP sends full internet route, select only based on the BGP. BGP select rule only based on the route but not real traffics, that may be cause port-A’s traffics have 8G, but port-B and port-C only have 4G, if want to adjust BGP select, only change RPL that more complex, and due to route from internet and multi ISP, so route maybe change at some time, in order to balance peering link, customer must continue to adjust their RPL.

Could we have more flexible and simplest way to resolve the issue? The answer is Yes 🙂 we can achieve the task by Segment Routing – Egress Peer Engineering. Now some customer had deployed the solution, that combine NetFlow, Openbmp to check AS/traffics of prefix, then send BGP LU(EPE label) to ingress node, and easy to control traffics.

完整阅读

Introduction

Refer to some CASE, customer concern why BGP take so many memory resource, and how to optimize BGP, and why memory not release after optimize, and so on. That hard to answer, in order to get answer, we need check more information. From the article, you can simple to know how to check BGP memory, and how to analyzing the BGP memory, those informaiton will help you and customer to do special optimize.

Solution

1. Default scenario, no any BGP route

关于BGP Feature：NHT（Next-Hop Tracking）。之前没接触过这个Feature，正好可以测试下。这个feature主要是当用户通过多个neighbor学来同样的前缀时，优选的下一跳地址在RIB里找不到了，那么他会自动切换到另一个下一跳，不用等待bgp neighbor 超时，这样可以加快收敛，这个Feature主要与IGP联动。另外为了防止默认路由使NHT失效，需要用route-map过滤非明晰路由。

测试Topology：
ASR1k——————CRS
完整阅读

第10章：多协议BGP和MPLS VPN

本章对MPLS VPN进行了整体的概括，包括基础概念，跨域互联，在此仅仅概述，详细内容可以看我以前总结的关于MPLS的相关文章：
http://www.zhaocs.info/tag/mpls

基础知识

1. RD是用来区分具有相同ipv4前缀的多条VPN路由，8byte，如下图：

2. RT是用来控制VPVN4的路由，即使与RD一样的值，意义也是不一样的
3. 4字节可堆栈的label结构，包含20 bits的label，3 bits的EXP，1 bits堆栈位，8 bits的TTL
4. TDP和LDP的端口分别为711和646
5. 标签0-15为保留，4-15暂时没有用到；在LDP中，初始路由器会发送“imp-null”
完整阅读