Cisco Cisco ASR 5700 トラブルシューティングガイド

Contents

Introduction

Problem

Troubleshoot

Solution

Introduction

This document describes the issue on sessmgr going to WARN state due to huge number of
HTTP flows. This issue is reported on Cisco Aggregrated Service Routers (ASR) 5x00.

Problem

Sessmgr status is WARN and high memory utilization.

These Error logs are generated in the process.There is no subscriber impact due to this error log.
As per design once the call is rejected from sessmgr which is in WARN state, system tries at
different sessmgrs and call goes through.

Troubleshoot

Capture s output and check for the command outputs to troubleshoot further.

The memory problem is related with the amount of flows that the sessmgr handles. The correlation
can be seen between sessmgr having high memory consumption and high amount of flows.

For affected sessmgrs (and for one unaffected), collect these command outputs, where x is the
Sessmgr instance.

Check if unoptimized rules and group of ruledefs consume lot of memory.

The highest memory consumption is due to these functions based on the command outputs.

You can also check Max No of Simultaneous HTTP Flows attained by Call lines

You can conclude that there are huge number of HTTP sessions being allocated and this could be
due to the heavy HTTP traffic. Also there are almost 1044671491 Calllines, which have greater
than 10000 HTTP flows at a time. This leads to high memory usage.

Solution

You have the CLI to limit the number of flows per subscriber

Cisco would recommend to configure flow limit-across-applications to 5000 as recommended
under all affected Rule-bases where huge number of HTTP Traffic can be seen.