Quick troubleshooting of transmission network

on

NCE-T

During network operations, issues do occur which could lead to massive outages. Being a network engineers we need to act fast and solve these issues timely. For quick and accurate troubleshooting, Operation’s guy needs sufficient service skills and strictly follow the rules to locate and rectify a fault in the transmission network

• Network Basics and Equipment Principles

• Engineering Networking Information

Initial Remarks 

Here are some quick tips & tools for isolating outage’s root cause that can help in resolution faster.

In transport network, for isolating issues we need to monitor the tunnel, PWE3, CES, control plane configure OAM functions on the NMS (NCE-T / U2000) to test connectivity and locate faulty points.

Today, I am sharing some most essential ones for quick resolution.

• • Smart Ping

  • Tunnel Ping

  • LSP Traceroute

  • VRF Ping  & Traceroute Test

• Smart Ping

Ping is a core tool for checking network connectivity and host reachability, if an node (PTN or any transport device) is having fault. 

Ping simply sends ICMP packets to host and it sends back determines 

• Whether the source and destination hosts can communicate with each other

• Round-trip delay in the communication between source and destination hosts

• Packet loss rate

Smart Ping Overview

Smart Ping is introduced to help users perform a Ping operation in one-click mode & improves Ping efficiency.  

With this, just need to enter the source IP address, destination IP address, and VPN name specific to a VPN scenario. The Ping module automatically combines the values of other parameters, reducing configuration complexity.

Procedure

• In the main topology, right-click a desired NE and choose NE Explorer from the shortcut menu 

• In the NE Explorer, choose Configuration > Control Plane Configuration > Ping and Traceroute from the function tree. The IPv4 Ping dialog box is displayed (see Figure # A1)

Figure # A1

• In IPv4 Ping,Put Destination Address (IP you want to test), VRF Name & Test Type. By using type as SmartPing we just (see Figure # A2, A3 & A4)

Figure # A2

Figure # A3

Figure # A4

Check Result for 

Figure # A5

Smart Ping Parameters

• Tunnel LSP Ping Test

An LSP ping test checks tunnel status and communication between the two ends of a tunnel. The following example illustrates how to perform an LSP ping test using the NCE-T.

Procedure

First you need to select TUNNEL

On NCE-T choose SERVICE > View > STATIC Tunnel from main menu (see Picture # B1)

Figure # B1

• Select Static Tunnel Configuration option > then select Manage Static Tunnel  (see Picture # B2)

Figure # B2

Search tunnel, specify the filter criteria and click Filter to search for tunnels that need to be tested. (see Picture # B3)

Figure # B3

Select Tunnel from list , right click > Diagnose  >  Test & Check  (see Picture # B4)

Figure # B4

Select the tunnel to be tested. On the Diagnosis Option tab, select Apply to All Path, and select LSP Ping under OAM Tool. Then click Run. The LSP ping test starts. (see Picture # B5)

Figure # B5

Select LSP Ping with setting & click RUN (see Picture # B6)

Figure # B6

Output (see Picture # B7 & B8)

Figure # B7

Figure # B8

• Traceroute for Tunnel route

LSP traceroute is used to detect tunnel link faults and locate faulty points. This illustrates how to perform an LSP traceroute test using NCE. 

Procedure

• On NCE-T, Step # 1 to 4 are same for selecting TUNNEL (see Picture # 01 to 04 above )

• Select the tunnel to be tested. On the Diagnosis Option tab, select LSP Traceroute under OAM Tool. Then click Run. The LSP ping test starts. (see Picture # B6)

• The LSP traceroute test starts. (see Picture # C1 )

Figure # C1

Testing output showing as Hop by hop output (see figure # C2)

Figure # C2

• VRF Ping  & Traceroute Test

VRF Ping Introduction

Ping test of VRF helps us to check whether the VRF (Virtual Routing and Forwarding) communication of L3VPN services is normal and whether IP communication between VRFs is REACHABLE. 

VRF Traceroute Introduction

VRF traceroute is used to detect L3VPN link faults and locate faulty points.  

Procedure

• On NMS, choose Service from the main menu then Select Static L3VPN  (see Figure D1)

Figure # D1

• Select Manage L3VPN static  (see Figure D2)

Figure # D2

• In the Set Filter Criteria   box, specify the filter conditions and click Filter to filter out the list of L3VPN services. (see Figure D3)

  

Figure # D3

• In the displayed L3VPN services list, right-click a desired L3VPN service and choose Test & Check   (see Figure D4) 

Figure # D4

•  In the Test and Check dialog box, click the link to be tested (or add a user-defined link). On the Diagnosis Option tab, select VRF Traceroute in OAM Tool, and click Run.

• View the check result in the Result dialog box.

Ending Remark

These are few important task/tools which will help you solving issue in transmission network by isolating it quickly. Let us know which tool helped you in finding route cause?