Robots not reporting to UIM hub on AWS

Products

• DX Unified Infrastructure Management (Nimsoft / UIM)
• DX Unified Infrastructure Management (Nimsoft / UIM)

Issue/Introduction

Robots configured for a particular hub are not reporting to the hub 

example

•  Robot version tried 9.30, 9.33 and 9.34.
•  Os version RHEL 7.9  x86_64
•  Bidirectional port TCP 48000 - 48050 and UDP 48000 - 48003 is opened.
•  Telnet is working fine from both hub and robot vice versa.

 

• Followed the steps in KB but issue persists

Troubleshooting UIM Robot-Hub connectivity or communication issues

Environment

Release : 20.4

Component : hub 9.34

Resolution

1) UIM Linux secondary hub hosted on AWS cloud environment

2)Errors in the robot controller log reporting to this hub 

 Line 75: Feb  7 18:50:26:557 [140178419017536] 0 Controller: failed to send probeport list to hub xxxx(10.xx.xx.xx) - communication error
 Line 80: Feb  7 18:50:27:559 [140178419017536] 4 Controller: CONNECT: 0x2116d30(7) 10.64.xx.xx/38104->10.72.xx.xx/48002
 Line 81: Feb  7 18:50:27:559 [140178419017536] 4 Controller: SREQUEST: probelist ->10.xx.xx.xx/48002

 

2) Checking the interface of the hub it was observed it was using MTU 9001 i.e which supports Jumbo frames 
 

 

The issue was resolved after changing the MTU of this interface to 1500 and restarting the Nimoft services on this hub 

Additional Information

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/network_mtu.html#jumbo_frame_instances