[AWS] File Level Recovery may fail if Elastic Load Balancing (ELB) is in use

Summary

Using FLR to explore volumes may fail if Elastic Load Balancing (ELB) is in use.

Description

When using FLR to explore files, you may get one of the following errors when the worker launches.

This could be caused by an ELB (Elastic Load Balancer) in your environment, as the default timeout is 60 seconds.

Please check the ELB timeout in your AWS console and increase it to fix the issue. The following is a link to the AWS Steps to adjust the timeout https://aws.amazon.com/blogs/aws/elb-idle-timeout-control/ 

When an ELB in your environment is causing a timeout, you may see the following in the cpm_server.log file

2020-01-29 22:22:18,242:[140151015565056][YXARihgZcW] ERROR: explore_backup_init(views.py:140) Failed to init explore session

Traceback (most recent call last):

File "./cpmserver/cpm/filemanager/views.py", line 137, in explore_backup_init

File "./cpmserver/cpm/filemanager/mount_volumes.py", line 153, in execute

File "/opt/n2wsoftware/python/lib/python2.7/site-packages/django/db/models/base.py", line 696, in refresh_from_db

db_instance = db_instance_qs.get()

File "/opt/n2wsoftware/python/lib/python2.7/site-packages/django/db/models/query.py", line 380, in get

self.model._meta.object_name

DoesNotExist: FLRWorker matching query does not exist.

If you experience the symptoms mentioned above, please increase the timeout on your ELB to at least 600 seconds, then test FLR after the increase.