Servcie engine crashes when using L7 persistence profile for an L4 Virtual Service

Products

• VMware Avi Load Balancer

Issue/Introduction

If a virtual service is configured with multiple ports, the application profile for one specific port has been overridden to a Layer 4 application profile.

Furthermore, the associated pool is configured with L7/Cookie Persistence.

In such a scenario, Service Engine can crash with a segmentation fault at  ngx_http_parse_multi_header_lines

To investigate further, you can review the latest stack traces from the Controller or SE by accessing the following path:

CLI:

Log in to the Controller via SSH and run this command. Please note you have to replace the name of se_dp file here.

root@<Controller ip>:#  cat /opt/avi/archive/stack_traces/<se_dp.timestamp>.stack_trace
 
UI:
Navigate to Administration > Support > Crash Reports > Expand the latest crash file.

 

Below is the sample configuration in Virtual Service and pool

Virtual Service Configuration

Pool Configuration

Note: The persistence used can be any L7 persistence profile. Above screenshot is just an example of one of the L7 persistence profile

Cause

On a VS with an L4 application profile, if the persistence profile is set to anything other than client IP persistence, SE fails.

Resolution

Change persistence type to System-Persistence-Client-IP in pool configuration.